One can only envy those car owners who have or got the opportunity to build their own real garage. Knowing the mentality of our men, it can be stated with a high degree of certainty that the vast majority of "lucky ones" will start building a "house" for their car with their own hands. Nowadays, there are many opportunities for choosing materials for building a garage - both from the standpoint of ease of self-construction, and from the point of view of maximum efficiency.
Any building is always crowned with a roof, and if, again, we focus on minimal costs, then its shed design becomes the best option. In addition, the problems of some special decorative effect, as a rule, recede into the background, giving way to the reliability of the design and the speed of its installation. It is precisely these qualities that the mentioned option possesses. So, a shed roof for: from carrying out the necessary calculations to installation features - in this publication.
What are the advantages of a shed roof, are there any disadvantages?
So, in most cases, a garage is considered precisely as an auxiliary technical room, therefore, in its design and construction, a utilitarian approach usually dominates - simplicity, reliability, and the creation of effective protection for the car from atmospheric precipitation. That is why shed roofs are so popular in this case.
- This design is simple for independent calculations. It is based on a triangle - the most "rigid" of all two-dimensional figures, which is described by simple and understandable geometric relationships.
- The cost of materials and components is always significantly lower than for even the simplest gable roof. It is important that saving lumber in this case does not in any way affect the reliability of the structure.
- Installation of a shed roofing system is simple and intuitive. For the independent construction of such a structure, it is not at all necessary to be a qualified craftsman - subject to technological recommendations, any garage owner can cope with such a task. This is another "plus" in terms of cost-effectiveness of construction - there is no need to resort to hiring specialists.
- Another advantage is the speed of work. You can cover the garage with a shed roof in a matter of days, while choosing a more complex truss system and time will take much more.
True, the owner of the garage, when choosing a pitched roof, will have to come to terms with some of its shortcomings:
- A shed roof is more susceptible to snow load - due to a slight slope, snowdrifts can form on its surface. This must be taken into account when making calculations.
- Such a design either does not imply an attic at all, or its operational capabilities will be significantly limited.
- There are certain difficulties in ensuring high-quality thermal insulation of such a garage, especially if the project does not involve at least a small attic space.
- Finally, not everyone likes the appearance of a shed roof, which does not involve any decorative frills. However, this is a matter of taste, and if desired, a pitched roof can be entered into the general "architectural ensemble" of one's country estates. For many, this disadvantage is not significant at all.
Shed roof garage options
The shed roof system is a series of stacked parallel to each other, arranged in such a way that one of their ends is raised relative to the other to a certain height to create a slope. The rafters become the basis for the installation of the necessary lathing, and already she, in turn, for the flooring of the selected roofing.
The excess of one edge of the rafters on the other can be provided in several ways:
- Even in the process of designing a garage, one of the walls is planned to be higher than the opposite, by an amount (the calculation of such an excess will be discussed below). The other two walls in this case are given the shape of a trapezoid.
This approach is very often practiced in frame construction. Even when drawing up the drawings, it is envisaged that the height of the supporting vertical racks of the frame on one side will be higher. Thus, at different heights, in compliance with the required ΔН, there will also be bars of the upper trim, which will play the role of a Mauerlat. As a result, a ready-made shed roof system is immediately laid, on which it remains only to mount the rafters, and then the desired crate.
Which walls will vary in height will, of course, depend on the chosen direction of the slope.
- It can be a cross slope, towards one of the sides of the garage. This method is attractive in that the rafters are shorter, and you can often get by with the simplest scheme, without creating additional supports for them.
- Another option is when the front wall of the building is higher than the back, and then the slope of the slope is organized back. The length of the built in this case, in relation to the garage, already reaches 5 ÷ 6 and even more meters, and one cannot do without their reinforcement.
- If, according to the project, both walls of the building are of the same height, or a shed roof is being erected on a previously constructed building, then you can organize the slope of the rafters by substituting racks of the same height ΔН under them on one side. Racks on top are usually combined with a strapping beam, which will begin to perform the function
In this case, the front part of the roof structure and the remaining open gable triangles after the installation of the truss system are simply sewn up with wood or other material, at your discretion.
This approach often allows you to achieve savings in the construction of the main walls of the garage - it will take less brick or blocks, and the laying process itself will go faster - there is no need to display additional side trapezoidal walls of the gables.
- If the walls are of the same height, then they resort to another method - they mount truss trusses on the "ground", and then install them with certain steps on the Mauerlat.
Usually in the course of work one such truss is made, carefully tried on and adjusted to the place. Well, then it becomes a template for "cloning" - the rest are made according to its model, in convenient conditions on earth. When all the farms are ready, they proceed to the final installation. The lower corners of the trusses are attached to the Mauerlat, the upper corners are tied together with a beam, creating a single rigid structure.
This approach is especially convenient when a large distance between the walls obliges the builder to strengthen the rafters. And the truss in itself is a rigid structural element, as it combines both a kind of floor beam and a rafter leg, with reinforcing jumpers installed between them - racks or struts.
Rafter mount
Another obvious convenience - in such a garage it will be much easier to hem the ceiling, if necessary, also insulate it - the horizontal beams of the trusses provide all the possibilities for this.
Another option is when the garage is attached to a finished solid wall of an already previously erected capital building.
In this case, one end of the rafters rests on brackets or a support beam installed on the wall at a certain height, and the other end rests on vertical racks with strapping - in the case of a frame structure, or on the Mauerlat of a nearby wall. In any case, this fulcrum is again located with the calculated height difference ΔН.
If necessary, instead of rafters, roof trusses can also be attached to the wall of the house, by analogy with the previously considered case.
The main parameters of the shed roof of the garage, their calculations
So, if a decision is made to build a shed roof over the garage, then it is necessary to determine its main parameters.
From the initial data, as a rule, there are only the dimensions of the "box" of the garage - its length and width. From here we will start to “dance”.
Roof slope direction
First of all, it is necessary to determine in advance the direction of the slope of the slope, guided not only by considerations of convenience and ease of installation of the truss system, but also taking into account the prevailing wind direction at the construction site.
The slope of the roof is recommended to be carried out precisely on the windward side, so that the movement of air does not create a lifting force, but, on the contrary, presses the roof structure down. Although the garage, as a rule, is a low structure, and can be almost completely buried from the effects of wind by other buildings, nevertheless, the predominance of the wind can be caused by the features of the terrain or neighboring buildings - open spaces, forest clearings, etc. And, of course, the specifics of the site can also play a certain role in choosing the direction of the slope - the general “background” of the design of the territory, the location of the elements of the storm sewer system, or other factors.
Determination of slope slope
The next step is to determine the steepness of the slope, that is, the angle α.
For shed roofs, this angle usually does not exceed 25, maximum - 30 °. With too much steepness, the structure itself looks ridiculous, and most importantly, the roof becomes very vulnerable to wind load. Too small slopes, less than 10 °, are also undesirable, since in this case the significance of the snow load on the slope increases sharply, the outflow of water becomes difficult, especially during thaws or the beginning of mass snow melting.
The slope angle is seriously affected by and. If the garage owner prefers one or another roofing material in advance, for example, in order to withstand the general design of the territory, then he must be guided by certain rules when calculating the steepness of a pitched roof.
Below is a diagram showing the acceptable types of roof coverings for various roof pitch angles.
Please note that the slope on the diagram is shown in three different versions - in degrees and in the ratio of the height of the lift (ΔH) to the base length (D or L), which, in turn, can be expressed as a fractional ratio or as a percentage. Having such a scheme at hand, it will not be difficult to convert one unit of measure to another.
The circled numbers indicate the types of roofing, and the arrow coming from them indicates the minimum allowable the amount of roof slope at which they can be used.
| Designation on the diagram | Permissible type of roofing |
|---|---|
| ① | Coating of shingles, wood chips, natural shingle. |
| ② | Natural piece tiles, slate and bitumen-polymer tiles. |
| ③ | Flat roof: at least four layers of bitumen-based roll coating, with an external dressing of fine gravel embedded in molten mastic. |
| ④ | The same, but three layers of material are enough with a mandatory sprinkle. |
| ⑤ | The same, but without the obligatory gravel backfill. |
| ⑥ | When using rolled material - two layers applied to the mastic in a "hot" way. It is allowed to use metal tiles or some types of corrugated board. |
| ⑦ | Asbestos-cement slate corrugated sheets of reinforced profile. |
| ⑧ | Clay tiles. |
| ⑨ | Sheets of flat slate reinforced pro |
| ⑩ | Sheet steel roofing, with seam connections of sheets. |
| ⑪ | Slate asbestos-cement wavy usual profile. |
How to give the ramp a given slope angle?
The next question is how to give the slope the desired angle of inclination.
If with a value α and we decided on the direction of the slope of the slope, then, knowing the initial parameter of the length or width of the garage (), it is easy to determine the required height difference ΔN, which has already been mentioned several times.
If the walls have a certain thickness (for example, they are made of blocks or bricks), then the measurement of the linear parameters of the building D and L draw along their outer edges.
To calculate, we use the well-known trigonometric formula:
H = L(D) × tg α
In order not to force the reader to look for tangent values and carry out independent calculations, a calculator is placed below that will allow you to perform the calculation in a matter of seconds. If desired, you can "play" with the values to find the best acceptable option.
Decking
Calculator for calculating the excess of the wall to ensure the required steepness of a pitched roof
It is not difficult to build a simple roof for a garage with your own hands. But to do it right, you need to be well prepared in advance. After all, you will have to take into account a number of important points - when and why to do insulation, whether vapor barrier is needed and what to do to eliminate possible leaks. In addition, depending on the condition and location of the building, the construction strategy will differ significantly.
What should you think about before installing a roof?
The first thing you need to decide is the purpose of the garage. If it is unheated and will be used only to store the car, the roof can be any, as long as it does not leak. But if the garage is planned to be warm or will warm up from time to time, being used as a workshop or a local "cafe for motorists", the roof must be insulated!
An uninsulated metal roof will condense, providing an unforgettable indoor rain experience in winter. Wooden or concrete will heat up, melting the snow outside. And this is fraught with ice stalactites and stalagmites, which will have to be knocked down regularly. And it’s good if the slope of the roof is made on the back wall, and not in front of the gate.
If there is an exhaust hood, it is also better to insulate it and raise it above the roof - so as not to drown the same snow.
Do not forget about the minimum slope with a mandatory drain for a flat roof. Otherwise, rain and snow can linger in bumps that cannot be avoided with self-construction. And this is fraught with possible leaks or destruction of the roof in a few years.
And, of course, it is better to correctly assess your strengths in advance and draw up an estimate. Since sometimes a cheap option is not suitable due to its complexity when arranging with your own hands, and expensive material can be replaced with something cheaper. After all, a garage does not need a special margin of safety and high environmental friendliness of the roof.
Do-it-yourself concrete roof for a garage
The easiest option is to lay concrete slabs. But you can't do without a crane. If its use is impossible for some reason, you will have to make a concrete screed yourself.
For this you will need:
Of the tools you should think about in advance:
It greatly simplifies the work with concrete, especially if the hand is not yet full, as shown in the video:
Pouring a concrete garage roof
So, all the materials are in stock, the tool is ready and you can start building the roof. For this:
- Floor beams are laid on the walls - pipes, channels or I-beams. In the first two options, the roof will be poured over. If the beams are made of an I-beam, boards or metal sheets are laid on its lower edge, on which concrete will be poured. When installing an insulated roof, foam can be laid under the screed.
- A reinforcing reinforcing mesh is knitted. It is important not to forget that the rods should not touch the formwork, because then rust may begin to appear at the ends. But reinforcement can be welded to the floor beams. The advantage of I-beams is the ability to fill "in layers" - one row at a time. This is especially important when pouring alone, since it will definitely not work to make the entire roof at once.
- Formwork is fixed. To make it easier to tear it off from concrete later, the inner walls must be smeared with used machine oil or any other cheap oil. Boards should fit as tightly as possible! Concrete "milk" coming through the cracks significantly degrades the quality of the monolithic floor.
- The armnet is poured with a concrete mixture, it must be bayoneted and smoothed out with a rule. If it is possible to order a ready-made concrete mix for pouring the entire roof at a time, you must definitely get at least two assistants to level the mixture with shovels. And it is better to require a deep vibrator with such a filling, which will help to quickly remove air from the mixture.
- The concrete screed is covered with plastic wrap and must be regularly watered. Without watering, concrete will not gain the necessary strength.
- After setting the screed, all cracks must be closed. This is done by ironing - cement is scattered on the surface with a thin layer and rubbed with an ordinary paint brush. The procedure continues until all cracks are sealed.
- All joints in the screed are smeared with mastic reinforced with sickle. The same applies to the outlet of the ventilation pipe, and the upper ribs of the channels.
- To ensure the required level of water tightness, a built-up waterproofing is laid over the concrete. Be sure to close the ends of the concrete floor! For this, the concrete is smeared with a primer, and the waterproofing itself is spread in two layers - for reliability. To prevent the waterproofing from lagging behind, the edges can be pressed with aluminum strips. The dowels are filled with bitumen, and the planks themselves are smeared with the same mastic reinforced with sickle.
Concrete roof restoration
But what if the garage was "inherited"? And along with the building, the accompanying problems in the form of a leaking roof and a crumbling concrete floor passed to the new owner? In this case, the restoration of the roof will not be much easier than pouring a new one:
You can also restore the current roof by making a ceiling of corrugated board or slate on top. To do this, without removing the old roof covering, logs are laid and fixed with anchors. The joints around the perimeter are sealed with mounting foam - for sealing and so that the wind does not lift the entire ceiling.
A crate is fixed on the logs. If the metal is thin, then it is desirable to make the crate frequent. The edges are protected by metal corners that prevent moisture from leaking from below. After the roofing is laid, the wind bar must be installed.
It is also called end - it protects the ends of the roof from water ingress from above.
It is very accessible about the restoration of the garage roof using corrugated board is shown in the video:
Do-it-yourself wooden garage roof
If concrete work seems complicated and time-consuming, the roof of the garage can be made of wood. More precisely, the truss system will be wooden, while the roofing itself can be anything - from metal to ceramic.
Shed garage roof
This is the simplest option that does not require serious calculations and special building skills. The only thing that will have to be taken into account with a detached garage is the prevailing wind direction. The lower edge of a shed roof should be on the windward side - that is, on the side where the wind most often blows. Otherwise, strong gusts can simply tear off the roof.
Such a roof is built extremely simply:
- A support board is attached to the wall of the house above the level of the garage wall. With a run width of up to 4.5 meters, the rafters will only be placed on the base board and the garage wall. If the width of the garage is planned to be up to 6 m, you will also have to fix the bed on the same level with the garage wall, on which the rafter leg will rest, providing support for the long rafter.
- If the walls of the garage are brick or concrete, a Mauerlat from a bar of 15x10 cm or 15x15 cm is attached along the upper edge. It provides the necessary strength to the entire roof structure, redistributing the load on the wall. So that the tree does not rot, the timber must be treated with an antiseptic and several layers of waterproofing should be placed under it.
- The rafters are attached to the Mauerlat either with a wall release or without a release. You can calculate the length of the rafters and the angle of inclination using the table.
- The waterproofing is laid directly on the rafters. On top of it, it is fixed with bars of the counter-lattice, on which the crate is then placed. The waterproofing is laid with an overlap, the places of overlap are glued with butyl rubber tape. Also, as a seal, you can put adhesive tape under the counter-lattice - to seal the puncture points.
- Depending on the selected roofing and the angle of inclination, the lathing can beat both solid and sparse. This should be taken into account, otherwise, under critical loads, the roof may simply fail.
double garage roof
This option for a do-it-yourself device is already much more complicated and requires serious calculations. Yes, and the material will also need more. For example, insufficient thickness of the rafters can cause the roof to sag, resulting in snow stagnation and bursting of the rafters due to weight. And even with the right thickness, a large number of knots in a bar can lead to the same results. But such a garage looks presentable, and the space under the roof can be used to store household equipment.
The principle of the gable roof device:
- It is important to determine the height of the roof - the wind will try to overturn too high, and it can raise too low.
- The rafter system is assembled - triangles consisting of rafter legs and puffs. For garages with a width of more than 6 meters, a more complex system using crossbars or headstock will be required.
- You can either collect individual elements on the ground, lifting them as needed, or immediately on the walls. The first option for garages is more suitable, since the ceiling does not spread and in this case walking along the edges of the walls is extremely inconvenient.
- First, the extreme rafters are installed from the ends of the garage. A cord is stretched between them at the highest point, which determines the level of the roof. After that, you can attach all the other rafter legs. They are fixed with temporary jibs.
- The ridge run is attached last. To prevent displacement of the rafters, they are fixed by cutting. Also, to simplify the work, the ridge beam can be fixed with building corners without cutting corners.
- The waterproofing is rolled out and fixed with a rail along the rafters. If a waterproofing membrane is used, it can act as a temporary roof for two to three months, depending on the manufacturer. You need to pay attention to UV resistance, otherwise the waterproofing can quickly become unusable, just starting to crumble.
- The crate is stuffed. The frequency depends on the roofing. It is better to make it more frequent than to repair the roof urgently later if the roof cannot withstand the pressure of snow.
Regardless of the chosen roofing, special attention should be paid to the ridge knot. A poorly made ridge is a guarantee of a leaking roof and the formation of condensate, since the ridge performs the function of ventilating the roofing cake.
For example, for a roof made of metal, the distance between the crate in the ridge assembly should be at least 3 cm and not more than 5 cm. And the waterproofing should be located on the roof slopes at a distance of 20 cm. The ridge itself is laid on a breathable insulation and fastened with self-tapping screws.
For a ventilated roof ridge with a soft roof, you can use both ready-made solutions in the form of a ridge aerator, or make the design yourself. The first method is much simpler, but significantly increases the cost of construction.
The second option will require a little more effort, but it will save you money. The construction of a ventilated ridge with your own hands begins with cutting a ventilation gap in a continuous crate. Next, 5x5 cm bars are attached above the ventilated hole, on which OSB sheets are laid. To protect the roofing pie from dust and insects, you can also fix a metal mesh that wraps around the bars.
findings
Summarizing, we can draw the following conclusions when building a garage roof with our own hands:
- it is better to restore the concrete roof of the garage with the help of corrugated board - it is easier and cheaper;
- concrete work must be carried out with an assistant, otherwise the roof will have to be poured in parts, and the joints sealed;
- roof insulation is a must for protection against condensate;
- for a concrete roof, built-up waterproofing is used on a concrete floor, for a wooden one - a windproof membrane that prevents the formation of condensate;
- the thickness of the rafters should be sufficient to withstand the maximum snow load, if the slope of the roof is small, it is better to do it with a margin of safety;
- if you choose corrugated board as the roof, as the cheapest option, you should carefully consider the quality of decorative spraying - for unscrupulous manufacturers, it can peel off in a year;
A flat roof is used not only in residential buildings, but also in auxiliary and household buildings. A garage with a flat roof can be not only practical and functional, but also an original structure. The flat roof is ideal for regions with little average monthly rainfall. However, even in areas with an abundance of precipitation and snowy winters, the arrangement of a flat roof is possible, provided that the supporting frame of the roof is strengthened and the allowable loads on the floor system are taken into account.
A flat roof has the following advantages:
- The building with a flat roof looks quite original and modern.
- On such a roof, you can equip a terrace, a recreation area, or use it according to the preferences of the owners.
- Since this design does not require a complex and expensive truss system, and also due to the small coverage area, garage owners receive significant money savings on the construction of this part of the structure.
- If you compare a flat roof with pitched structures, then its repair is much easier and does not require much time from you.
The only drawback of such roofs is the need for careful design and calculations of the future structure, taking into account the maximum allowable loads and the type of roofing. If mistakes are made at this stage, the roof may not only leak, but will also be unable to withstand the weight of the snow cap and ice.
Attention! When designing flat roofs, a slight slope of the surface is laid for the flow of melt and rainwater. This slope must be within 4°.
Varieties of flat roofs
Reinforced concrete floor slabs or metal profile beams can be used as the base of a flat roof. The structure of the roofing cake and the sequence of its implementation are directly related to the type of base used.
All flat roofs are divided into several subspecies, depending on the method of forming the roofing cake:
- monolithic roofs in a classic design;
- structures from corrugated board;
- inversion coatings, which can be attributed to a special version of the traditional roof.
All of the above structures are divided into non-exploited and exploited, depending on the strength and bearing capacity of the base.
Monolithic roofs
Monolithic roof structures for the garage are considered classics. They belong to the category of soft roofs. The roofing cake of such a roof consists of the following layers, arranged from the bottom up:
- The base is a reinforced concrete slab for the arrangement of floors.
- A film vapor barrier is laid on top of it.
- This is followed by a layer of thermal insulation material. Usually mineral wool is used for these purposes.
- A waterproofing roofing carpet is laid on the insulation. As a waterproofing, roll material containing bitumen is used.
- If the roof is exploitable, then a concrete reinforced screed is made. To reinforce it, a metal mesh is used. After that, if necessary, an additional layer of waterproofing and tiling can be laid.
Sometimes, for arranging a flat monolithic roof, metal I-beams with a height of 120-150 mm are used. Further, the construction is carried out as follows:
- A continuous crate of wooden boards 2.5 cm thick is mounted on the lower shelves of these beams, which are covered with roofing material.
- After that, the reinforcing mesh is laid so that it is at a distance of 30-50 mm from the roofing material.
- The space between the beams is then filled with concrete.
- When the mortar sets, a classic soft roll roof is installed.
Quite often, flat roofs of garages are made from a bearing profiled sheet. This is the most economical option for arranging a flat roof structure. But this option is only suitable for unexploited roofs. The design of the roofing pie in this case practically does not differ from that described above, with the only difference being that an additional layer of heat insulator is required.
Classic design
Such a construction in a section looks like a multilayer structure, which should include the following mandatory layers:
- flat base (concrete, from metal beams or bearing profiled sheet);
- vapor barrier layer;
- a layer of thermal insulation material;
- waterproofing carpet.
Polyethylene film is usually used as a vapor barrier. It reliably protects the roof structure from warm air vapor rising from the room and causing condensation in the thermal insulation layer.
The following materials can be used as a heater:
- expanded clay-gravel mixture;
- mineral wool boards;
- polystyrene foam insulation.
The waterproofing carpet is made of roll materials produced on the basis of bitumen. Spray membranes and special mastics can also be used for this.
Inverted roofs
The design of the inversion roof is fundamentally different from the options discussed above. In cross section, such a roofing cake has the following layers:
- The base is a flat concrete slab.
- A waterproofing roofing carpet is attached to it using a bituminous primer.
- Next, a slab of rigid heat-insulating material is laid.
- This is followed by a drainage layer and a reinforced coating.
- After that, geotextiles are laid, which protects the insulation from the negative effects of external factors.
- The final layer of an inverted roof can be any material suitable for these purposes, for example, paving slabs, a fertile layer with grass.
Important! The inverted roof can withstand significant loads, so it can be used as an exploited roof.
General device rules
According to the requirements of SNiP, a flat roof must be made with a minimum slope to one side in order to avoid the accumulation of precipitation on the coating and leakage. It is worth remembering that even the minimum amount of moisture lingering on the coating can lead to rapid damage to the structures of the roofing pie. This is because, due to repeated thawing and freezing of moisture, the structures are deformed and destroyed.
To form the required angle of inclination, either load-bearing elements (beams or floor slabs) are used, which are mounted in accordance with the required slope, or a special expansion of expanded clay is performed.
It is also worth remembering that there must be a separating layer between the insulation and the layer of loose material. Soft roofing is laid in two layers with overlapping strips. In this case, the direction of laying strips in two layers should be mutually perpendicular.
The garage in our time is used as part of the garden plot design ensemble, where all buildings are erected in the same style. To successfully fit the design into the overall picture, it is best to choose a gable roof for it. It is very practical and, with the proper level of skill, can be made by hand.
Gable roofs are distinguished by the availability of do-it-yourself construction and ease of operation.
A gable roof is a covering of a building with two slopes, that is, a structure that has two inclined surfaces. The frame at this roof, due to its design features, combines ease of construction and maintenance with a long service life and reliability. These characteristics make the use of a gable roof a reasonable solution when building a garage.
The simplest is a symmetrical gable roof. Symmetry gives a uniform distribution of the impact of external factors on the Mauerlat and the load-bearing walls of the building. There is no possibility of bending the rafters along the length, various spacers and supports are placed in any necessary place of the structure.
Advantages and disadvantages
The gable roof of the garage is a structure that uses external fences of the structure (walls) for support. The planes of the roof are connected at the highest point of the roof - the ridge. Geometrically, the base and two slopes of the roof form an isosceles triangle..
This garage floor has several positive qualities:
- Easier removal of water masses and snow. The slope improves water drainage, which reduces the load on the roof, and the need to remove snow from the roof is infrequent. In regions with heavy snowfall in winter, a gable roof is the best garage structure to withstand the snow load.
- The article of savings will be the refusal to use hired construction teams - the home master is able to independently build a gable roof on his garage.
- The shape of this roof reduces heat loss in heated garages. This is the most energy efficient design for covering outbuildings.
- The gable roof makes it easy to organize a place to store tools and other things in the attic.
- You can increase the height of the ceiling.
Please note! A building with a gable roof, outwardly looks like an independent building, in contrast to structures with a single slope. It can be placed not only next to the house - a beautiful garage with a gable roof looks good anywhere.
The main disadvantage of a standard gable roof is a lot of wood parts that need high-quality treatment with antiseptic compounds and fire retardants (anti-burning agents). In addition, the sloping design bursts the walls, so it is not suitable for garages with weak walls.
Calculations
The formula for calculating the gable roof of the garage
It is important to understand that the rafter system is assembled from a mass of triangular structures. If the slopes are made with a different slope, then it will need to be divided into separate parts and calculate the possible load. After counting each part of such a roof, the data obtained are added up.
When building the roof of any garage, the first step is to create a project that will indicate all the important design parameters. Before work, it is necessary to determine the three main characteristics of the design of a gable roof: the type of coating, the slope of the slopes and the installation height of the ridge. Calculations are carried out taking into account future loads on the frame. The total mass of the future roof is calculated taking into account the average weight of the materials used.
To prepare a working scheme, perform the following calculations:
- Taking into account the future slope of the slopes, the height of the ridge is calculated. The height from the ridge to the bottom of the roof is considered as the height of an isosceles triangle, which is formed by the base of the structure and the slopes. The calculation is made using the formula - h = 0.5 * b / tg (α / 2), taking α for the slope of the roof and b for the width of the building. To create a roof slope of 20-30 degrees and arrange storage in the attic, it is enough to place the ridge at a height of 1.5 meters.
- After that, the size of the rafters is found according to another formula - l \u003d 0.5 * b / sin (α / 2), where they take α for the slope and b for the width. The length of the rafters must be found in order to find out which kind of truss frame for this garage is best to use. To form the overhang of the cornice, which protects the walls of the building from precipitation, 30-50 cm are added to the resulting size.
Calculation of the steepness of the slopes
The slope of the slopes affects what kind of roofing you can use. For most buildings, the optimal slope slope is 20-30 degrees. It makes it possible to cover the roof with roll materials, slate, corrugated board or soft tiles. For metal tiles, a slope of at least 35 degrees is required.
Calculation of possible load
Table for calculating the possible load
Several types of loading are possible on the rafter system:
- Constant loads.
This is the weight of all structural elements, heat-insulating material, battens, etc.
The mass of roofing materials can be found in the table, the data are given for 1 sq.m.
- Variable loads.
Influence periodically and with different strength. These include the impact of precipitation, the mass of snow, the strength of gusts of wind.
The slope of the roof is very similar to a sail: if it does not have enough strength to withstand the effects of the wind, then the roof may collapse. This indicator is calculated by the formula: wind load = indicator adopted for the region in which the garage is built. This figure is multiplied by a special coefficient, which can be found in the SNiP "Loads and Impacts". It also takes into account where the site with the garage is located. For example, if there are tall buildings around the building, then the loads on it will be weaker. A detached garage is exposed to strong winds.
- Snow loads.
Snow load calculation
Equal to the mass of snow multiplied by a special coefficient that takes into account the pressure of wind currents. According to SNiP 2.01.07-85, the weight of snowfall per 1 sq.m. roofing is 80-320 kg / sq.m.
Please note! If the slope exceeds 60 °, then the load from winter precipitation does not affect the calculations - the fallen snow will simply slide off the surface and have no effect.
- Special loads.
Such loads are taken into account in regions with possible storm winds, tornadoes or seismic activity. In our country, it is enough to provide a margin of safety.
The impact of several factors at the same time creates a synergy effect - this feature also needs to be taken into account.
Calculation of the total load on the rafter legs
Calculation of the angle of the roof
Calculation of the angle of the roof
The slope of a gable roof is calculated taking into account the roofing material intended for installation. They have their own requirements:
- Ondulin, profiled flooring, slate, metal tiles require a roof slope of 20-45 degrees;
- Soft roofing requires a roof slope of 5-20 degrees.
It must be taken into account that increasing the angle creates more space in the attic, but at the same time increases the amount of material needed, which increases the cost of construction.
Attention! The slope angle of a gable roof must be greater than 5 degrees.
Rafter installation step
When building a gable roof, the distance between the rafters is taken within 0.6-1 meter. The choice of distance depends on the mass of the roof. The number of required rafter legs is found by dividing the length of the roof slope by the distance between the rafters + 1. The number found shows how many legs are needed to create a slope.
Rafter size
Calculating the size of rafters using the Pythagorean theorem
The length of this roof element is calculated using the Pythagorean theorem.
- Roof height "a" - the size is determined independently, the possibility of creating storage space in the attic and material costs are taken into account;
- "b" - 1/2 the width of the building;
- "c" - is located as the hypotenuse of the triangle, equal to the length of the rafter without the overhang of the cornice;
- "d" - overhang of the eaves, determined independently.
Important! At least 0.6-0.7 m is added to the found size to create the necessary cuts and make the overhang of the eaves.
Keep in mind that the industry produces timber longer than 6 meters. If the construction of the truss system requires an even longer timber, then it will have to be spliced (connected from several parts).
Reliable ways to connect the timber (using long nails and studs) can be seen in the photo.
Beam connection options
Rafter section
The required height and width of the rafter is determined taking into account several points:
- Future load on the structure;
- The material used - for example, a log, sawn timber and glued laminated timber can withstand different weights;
- Rafter size;
- The wood from which the roof is erected;
- Spaces between rafters.
The calculation of the cross section of the beam in the process of manufacturing rafters with a known length of the rafters is made according to the table.
Table for calculating the cross section of a beam
Beam and boards for a gable roof:
- Mauerlat thickness - 100x150 mm .;
- The thickness of the puff and rafters is 100x200 mm, sometimes a beam of 50x150 mm is used;
- Struts and runs - 50x150 mm;
- Rafter rack -100x150 mm;
- Lying - 50x150 mm (possibly less, taking into account the width of the rack);
- Lathing details - 20x100 mm, 25x150 mm (including roof material).
Necessary materials and tools
You will need the following tools:
- Middle hammer;
- Rubber or wooden mallet;
- Nail Puller;
- Construction levels of several sizes;
- Long plumb;
- Plastic or wooden rail about 1.5 meters long;
- 5-meter tape measure;
- Power tools: screwdriver, electric drill, grinder, etc.;
- Ordinary hacksaw;
- Slick;
- 2 ladders;
- stapler.
Mandatory materials for work:
- Metal corner for attaching rafters;
- Metal staples;
- Anchors, nails and wood screws;
- Beams for the manufacture of Mauerlat;
- Material for the manufacture of rafters;
- Beam for crates.
It is necessary to use high-quality wooden elements. Take only dry, pre-prepared wood. It is advisable to prepare material from conifers - it is stronger and lighter than raw wood. If you bought a material that was deformed during drying, it will have to be brought into the required state in advance using a planer.
Attention! For work, material with a moisture content of up to 18% is suitable. Raw wood, when dried, will bend, which will violate the strength of the structure.
Preparatory work
The work on building a roof for a garage is complex and time-consuming. Most of the operations are performed at height in uncomfortable conditions, so it is advisable to involve assistants. Before starting work, you need to bring and prepare all the materials. First of all, you should deal with lumber - stack it so that the wood does not deform, and perform the necessary processing.
The treatment consists in applying compounds that have fire-fighting and antiseptic qualities - this will reduce the risk of fire and give the material resistance to the development of fungus, biological damage and insect infestation of wood. Antiseptic preparations are sold ready-to-use and in the form of a concentrated solution. The concentrate must be diluted with water according to the attached instructions. To improve the quality of processing, it is advisable to pre-sweep all surfaces from small sawdust and dust.
The material is covered on all sides with a roller, turning over during processing. After impregnation, the lumber is placed in a pile and so kept until the solution is absorbed. At this time, the base of the walls is being prepared for attaching the Mauerlat.
The upper edge of the bearing wall of the garage, on which the Mauerlat is mounted, must be well aligned. First of all, waterproofing is laid on top of the walls - rolled roofing material is suitable for this. It is put on mastic or “dry”. Mauerlat mounts are placed between the rafters, it is advisable to install anchors in increments of 600-800 mm. Since we already know the distance between the rafters, after attaching the Mauerlat, markings are made for the rafter legs.
Instructions for the construction of a gable roof garage
The work can be divided into several stages.
Mauerlat is attached to the top of the wall
A beam intended for the manufacture of a Mauerlat is attached to the upper part of the wall on which the rafters will be laid.
For garages made of brick or porous material, the Mauerlat is mounted along the entire upper part of the wall.
Mauerlat connection
The timber impregnated with antiseptic solutions is sawn down at an angle of 90 degrees. The parts of the Mauerlat are joined using bolts of at least 8 mm in diameter. It is impossible to connect mauerdat with wooden dowels, wire or nails.
Beam installation
The beam is attached to the top of the wall. They do this in two ways:
- Offset to the side;
- In the middle of the wall.
To protect the beam from dampness, before mounting on the wall surface, a waterproofing layer of ordinary roofing material is spread. Since the structure is under severe wind load, the Mauerlat must be securely fixed to the top of the wall.
Mounting methods
- Anchor bolts. Great for walls made of monolithic concrete.
- Wooden dowels. They are used when attaching to wooden walls, but they need to be reinforced with additional fastening.
- Studs or staples. Suitable if the walls are made of porous materials.
- Hinged mount. Mounting the Mauerlat in this way provides the necessary displacement of the rafters with possible shrinkage of the building.
- soft wire. Used as a reinforcement.
Rafter manufacturing
Rafter structures can be made in 2 ways:
- Installation of rafters directly on the roof. This is rarely done, because it is difficult to take measurements, trimming and other work at height. But this allows you to perform all the actions without assistants (with a small size of roof trusses);
- Connecting all the elements on earth. In this case, large parts of the structure (pairs or triangles) are assembled on the surface of the earth, after which they are lifted up. This method speeds up work at height. But the mass of parts of the truss structure requires lifting equipment or the involvement of assistants.
Prepared truss pairs are lifted onto the walls and attached to the Mauerlat. At the bottom of the rafters, a gash is prepared in advance.
Attention! Since the cuts on the Mauerlat will significantly reduce its strength, the cuts are prepared only on the rafters. To make the same cutouts exactly in size, use a plywood template.
Methods for mounting truss structures are shown in the figure.
Rafter mounting options
The first rafter pairs are placed on opposite sides of the roof.
A cord is pulled between the extreme pairs of rafters - it will make the subsequent installation of rafter pairs easier, and at the same time indicate where the roof ridge should be. After that, the rest of the rafters are placed in the places marked for them.
Installation of the skate
Rafter connection options
The ridge knot is equipped by connecting the rafter legs in the upper part.
This is done in several ways:
- Without support bar;
- With rafter beam. This is how roofs are created on large garages. Subsequently, the beam can be used as a support for the rack;
- The method of laying on the beam. Modern method of ridge knot device.
- Cutting.
When the rafters are installed, it is necessary to securely fix all parts of the structure.
Lathing installation
Can't do it without a crate
It is necessary to make a crate, roofing material is attached to it, and it helps to move along the roof during work.
The step of the lathing is selected taking into account the roofing material used:
- For laying metal tiles - 350 mm;
- For laying slate and corrugated board - 440 mm;
- For a soft roof, a solid crate is needed.
Differences between warm and cold roofing
After fixing the crate, a roofing is laid on it. It is overlapped so that the seams are sealed. At the end of the installation of the coating, the drain is fixed, the gables are insulated and sheathed.
Remember! If you are building a heated garage, then you need to insulate the gables and roof slopes. For this, fibrous non-combustible heat-insulating materials are suitable - for example, you can use polystyrene foam or basalt wool.
Features of care and operation
Roofs should be cleaned and inspected annually.. Constant monitoring will allow you to notice the threat in time to prevent subsequent destruction.
A roof made of corrugated board is functional and lasts a very long time thanks to a reliable polymer layer - it protects the roof covering from corrosion. Constant exposure to moisture and low temperature, UV radiation, various pollution cause the destruction of the polymer coating. For this reason, roof cleaning is a necessary work to increase the service life. Cleaning is conveniently done with a jet of water, directing it down the slope.
Snow rarely collects on the polymer coating, and the matte surface does not allow it to slide down. Roof cleaning is carried out using tools that cannot damage the material. A wooden scraper with a soft rubber pad is suitable for this.
Soft roofing is subject to the same effects as other coatings. Timely preventive inspections will allow timely detection of defects in the roofing carpet and quickly eliminate the shortcomings.
A roof covered with natural tiles requires almost no maintenance. Cleaning of the coating from the fallen snow is carried out with scrapers, a spatula and a soft whisk, which will not damage or move the tiles. Seasonal inspection includes checking hook strength and detecting leaks. Work is performed in soft shoes every 4 years.
The construction of a gable roof on a garage requires compliance with safety requirements, like any work at height, while it is necessary to adhere to the rules of electrical and fire safety. Only in this way the roof will serve you for a long time and at no extra cost.
One of the important elements of any building is its roof, which is exposed to various physical and climatic influences. Its reliability and service life depends on the chosen material for its coating - the roof. The modern market offers many types of such finishing materials that can be selected for certain climatic conditions and features of the building on which they will be used.
Peculiarities
The roof of the garage and its roofing is practically no different from other standard structures of this type: they are used to protect the main building from moisture. But those that are on the "homes" for vehicles are almost always simple. This is due to the fact that during the construction of such systems there is no need to create beautiful structures for the purpose of decoration. As materials, they usually use the same products that are used in the construction of standard roofs for industrial or residential buildings. Very often, instead of the usual ones today, insulated mansard roofs are made, the premises under which in the future can be turned into a small dwelling. But such designs are relatively expensive and rare.
materials
The arrangement of the roof on the garage involves the formation of a reliable protective layer that will prevent the penetration of moisture into the building. Therefore, for such purposes, in most cases, coatings of several layers are used.
The following products can be used as the top coating of the roof:
- Ceramic tiles. The material can be attributed to environmentally friendly and durable. Among the advantages, anti-corrosion resistance, minimal destruction by microorganisms, as well as the ability to withstand significant temperature changes should be highlighted. The disadvantages include the high cost, as well as significant weight, which makes it possible to lay ceramic tiles only on strong frames, the slope of which does not exceed 12 degrees.
An alternative to this product today is a metal tile, characterized by low weight and ease of installation.
- Ondulin excellently proven as a roofing material. A roof made of it can serve for more than 20 years, and it practically does not collapse under the influence of external negative factors. Relatively light weight and low cost. This combination allows you to form a roof not only cheaply, but also quickly. The only drawback can be considered the flammability of ondulin, but if you minimize the likelihood of it igniting under the influence of external factors, then it will become the best option when building a garage.
- Decking appeared on the market for a long time, but only recently gained immense popularity. This material is a thin sheet of metal, which is given a certain shape that increases its strength. To protect steel from rapid corrosion, the upper layers of the product are coated with galvanizing and polymer compounds that prevent moisture from entering the metal itself. Products of this type are lightweight, easy to install and durable. There are many color options on the market. Such coatings are very durable, but if the top protective layer is damaged, then the metal starts to rust very quickly. Therefore, for roofs it is desirable to use only high-quality products from well-known manufacturers.
- Slate obtained from various shale rocks, which are pressed in special machines. This roofing material resists temperature extremes well, and is also not afraid of exposure to various chemicals. It does not support combustion. However, slate sheets are heavy. This, in turn, complicates the installation. They are also very fragile, so it is advisable to work with them carefully and with the help of a special tool.
- Galvanized steel sheets Outwardly, they are flat canvases that are attached to the base with special screws or nails. The disadvantage can be considered high "noisiness" - the material makes loud sounds in strong wind and rain, as well as the likelihood of corrosion processes with constant exposure to moisture.
- Soft tiles. Outwardly, it resembles roofing material, but it has a more beautiful pattern. It is produced in the form of small parts of various sizes and shapes. The material is very durable, but it requires a perfectly flat surface for installation, so you need to nail additional sheets of moisture-resistant plywood or OSB to the rafters, and then lay such tiles on them.
Waterproofing materials should also be considered.
- Ruberoid is produced in rolls, which cover the roofs in order to prevent their leakage. Please note that it can be used as a substrate or as a main roofing material. It is used quite rarely on wooden bases, since the canvas does not have a design design, and also ignites well. At the same time, this universal product is almost indispensable for flat roofs, where they are protected by concrete bases.
- Bicrost. This is another type of waterproofing substance. Use it as a substrate. In many properties, it resembles roofing material.
- Bitumen or liquid rubber. Such materials are obtained from substances based on petroleum products, and are used to protect shed concrete roofs. In molten hot form, these compositions are simply applied to the base. This leads to the formation of a uniform layer that fills all the cracks and does not allow water to penetrate into them.
Types of structures
Today, when building garages, you can use one of several types of roofs:
- Flat. The angle of inclination of such a plane is minimal (up to 3-5 degrees) or completely absent. Such structures in most cases are monolithic concrete floors. They are found in large industrial garages, which are built of brick or other durable material. In everyday life, a flat roof can be made of wood, but it will not be able to hold a lot of snow in winter for a long time.
- Shed. A roof of this type is characterized by the presence of one plane, which is sloped relative to the frame. The device of this design is the simplest. You can even build it yourself without the appropriate skills. The angle of inclination here often does not exceed 30 degrees. This is due to the fact that the width of the roof is significant and if you increase the slope, then the base simply may not withstand the load.
- Gable. Roofs of this kind are the most common and practical. The systems are simple and fast to build. The angle of such surfaces can be brought up to 45 degrees. Please note that the slope may be different on each side of the slope. This approach allows you to give the structure the shape of an irregular triangle. The practicality of the system has long been known. If you choose the right height, you can create a small attic under the roof for storing things. A variation of this design are mansard roofs. They differ in the height of the room under the roof, which allows you to place a living space here. But such an option for garages, as already mentioned, is not so common.
slope angle
Today, garage buildings can have a different shape and structure. It all depends on the needs of a particular owner. But when building or repairing, it is important to choose the right roof slope.
The ability of the surface to withstand various loads, as well as the possibility of coating with various materials, depends on this parameter.
There is no universal angle for a garage roof slope.
It all depends on the finishing materials with which it will overlap:
- Up to 20 degrees. Such roofs are usually shed. For such surfaces, coatings such as asbestos-cement sheets, clay tiles, steel sheet are used.
- 20-30 degrees. This angle is the best option for most types of garage roofs. Such a slope allows the snow not to linger, and also to use almost all materials for finishing, from soft tiles, slate to various roll coatings. Please note that previously this factor was usually not taken into account during construction, so the rise of the structure does not always correspond to this value.
- 35 degrees or more. This angle is steep, which is not always good for roofing material. For such slopes, experts recommend using a metal tile that can withstand this load. It is not advisable to lay this material on roofs with a smaller slope. Therefore, if you plan to use this finishing product, you will first have to lift the entire system if it does not meet the specifications.
When choosing an angle and material for overlapping, it is also important to consider several more factors:
- The power of the wind. It is important to determine the maximum indicators of wind load and their direction. For this, special wind maps are used, on which the percentage of wind loads throughout the year is plotted.
- The amount of precipitation. Particular attention should be paid to snow, as it is able to accumulate and compact. If there is a lot of such precipitation, then it is better to use roofs with an angle of more than 20 degrees. When it is not possible to do this, the frame of the structure should be strengthened as much as possible so that it can withstand the upcoming loads.
How to calculate the amount of materials?
Self-installation of the roof very often involves the purchase of roofing materials. But before you go to the store, you should count the amount of this product.
The algorithm for calculating material volumes can be reduced to the following sequential operations:
- Finding the angle of inclination. It is needed in order to calculate the surface area. This operation can be carried out using mathematical formulas. In order not to use trigonometry, the easiest way to find the width of the slope using the Pythagorean formula. Initially, measure the height of the ridge and the distance from the center point to the edge of the roof. Theoretically, you get a right triangle. Having received the values of the legs, you can find out the length of the hypotenuse. To do this, use a simple formula, where a and b are legs.
Please note that this approach can be used for both single-pitched and double-pitched roofs.
- Having learned the width of the slope, it is easy to get the total area of \u200b\u200bthe entire roof. To do this, you need to measure the length of the garage along which the material will be laid. The area is calculated by multiplying the width and length by each other.
- At this stage, you need to find out the amount of finishing materials that are needed to cover a specific area. For gable roofs, calculations should be made separately for each half. The technology is quite simple and involves dividing the total area by the size of one roofing unit, taking into account a certain coefficient. For example, if one sheet of corrugated board has an area of 1.1 sq. m, then to cover 10 sq. m roof should take 10 whole sheets. It is important to bear in mind that during installation, some products are laid a little on top of each other. The number of sheets may also depend on the width and length of the roof itself. Very often, these numbers are not integers, so the material will have to be cut at the end. In some cases, it is possible to use leftover products for this.
It is not always possible to accurately calculate the number of roofing products. Therefore, it is better to take a little more materials when calculating. But if you have a familiar roofer, then contact him, he will help you calculate this figure with a minimum amount of waste.
Waterproofing
Excess moisture inside any room can lead to the rapid destruction of all finishing materials. Therefore, when arranging roofs, including garage ones, you should take care of high-quality waterproofing.
Today, this problem is solved using several types of materials:
- liquid formulations. This includes all products based on bitumen. They are sold in the form of liquid or solid elements, which must be brought to a liquid state before use. Mostly flat roofs with a slight slope are painted with bitumen. Apply the composition with a brush or a special sprayer. In this case, all cracks are completely sealed. Such products are used mainly for concrete roofs, but theoretically they can cover other substances. Please note that mixtures can be used both outside and inside the building. Therefore, they can be used as aids.
- Roll materials. Products of this kind are long sheets that cover the roof frame. They are located directly under the finishing material. Their classic representative is roofing material. But today, more and more often, special membrane sheets are used for such purposes. Attach them directly to wooden logs with a stapler and staples. It is important that adjacent sheets are laid with a slight overlap. All joints are insulated with cold welding or special adhesive tape. Please note that all waterproofing sheets should form a kind of drain. Therefore, the lower ends necessarily protrude beyond the edge of the lags.
Waterproofing is an important step that must be carried out when arranging the roof.
The service life of the entire structure depends on how well it will be performed.
Installation subtleties
The technology of finishing the roof depends on the design itself and the selected material.
Let's start with the coverage of reinforced concrete floors, consisting of the following sequential actions:
- Cleaning of concrete. There should be no dirt and large inclusions on the surface of the material, as cleanliness will contribute to better adhesion of materials.
- Application of liquid bitumen. Please note that some formulations need to be heated. Cover the surface with special brushes or sprays.
- Ruberoid laying. It is laid immediately after lubricating the roof with bitumen. This is important, as the composition quickly hardens and loses viscosity. During installation, the roll gradually spreads and evenly pressed against the base. You can simplify this task with the help of special rollers.
- Installation of subsequent layers. Their number is often equal to 2-3 pieces. The application algorithm is similar to the previously described principle. But when arranging the following sheets, it is important to consider the location of the joints. It is desirable that the top layer of roofing material overlap them. At the very end, the entire surface of the roof is carefully lubricated with bituminous mastic.
Now consider the principle of mounting structures located at an angle. These operations have many nuances.
Covering these roofs has several common actions:
- Framing arrangement. Technically, it consists of several wooden boards that are located throughout the entire area of \u200b\u200bthe roof. They are needed to create a base to which the finish will be attached. The step between the boards is selected individually. Some finishing materials require a completely solid base without gaps (soft tiles, etc.).
In this case, the logs should be closed with sheets of moisture-resistant OSB.
