With the attic you can quite easily increase the living area of the house. This structure is built in the attic and can be used for living, but only on condition that the rafter system of the attic roof is correctly designed. We will consider the manufacturing technology of such a design in our article. After all, it is this issue that should be given most of its attention in the design.
A little bit about the features
Attic - this is a room that is located directly under the roof of the house. The facade of this design is fully or partially formed by two surfaces of the roof. This is a fully-fledged floor, it can contain either one or several rooms, it all depends on what parameters the system has.
Attic. This word came to us from faraway France, in 1630, one architect came up with such a simple way to ennoble attic rooms. Not surprisingly, the architect was named Francois Mansart. It is from the surname that the design takes the name.
The main feature of the rafter system is that the design has an original and unlike anything appearance. But since the room above is residential, it is necessary to lay several layers of steam and moisture insulation, insulation material under the roof. It is also worth noting that the load on the walls and foundation increases with the installation of the rafter system of the attic roof on the house. Therefore, it is more reasonable to use light materials during construction.
Pros and cons of attics
You can highlight the positive qualities of the attic:
- Infrastructure is used from the building on which the construction is carried out.
- Significantly increases the area of the house.
- The building takes on an original and attractive appearance.
- Heat losses are reduced, and the energy consumption of the entire building in the cold season is also significantly reduced.
But there are two big disadvantages:
- The ceilings are beveled, but if the layout is done correctly, it will not be very noticeable.
- Skylights are of great value. When installing such windows, it turns out to give an attractive look to the house, but if you decide to save, you can refuse them.
Quite often, such structures are used in the construction of individual houses. Need to give a few numbers. Heat losses through the roof of the building are reduced by almost 10%, and in extreme cold this is extremely important. In addition, the cost of building an attic is much lower than the cost of building a full floor.
Shed roof
A shed roof is the easiest option for arranging the roof. There is only one ramp that is installed on the walls of different levels of the house. This is how the formation of the angle of the ramp occurs. It is worth noting that it is recommended to make a slope of not more than 45 degrees. But it needs to be over 35 degrees. If you make a small slope, then the snow will accumulate on the roof in winter, and this can increase the load on the house, so you will have to install additional supports in the attic.
But if you make too much a bias, then this will not add to the convenience of using the floor. The design of the rafter system in this case is very simple. It is worth noting that additional supports will not be required if the distance between the opposite walls is less than 4.5 meters. The roof looks very original despite the fact that it has a very simple design. As a rule, a window is made from the side of a high wall. With it, you can well illuminate the entire space of the room.
Gable roof
This option can also be called simple, because of this it is widely used. The main thing is to ensure that the height of the roof makes it possible to equip a living room under it. The roof structure is very similar to the gable roof system. It can be either symmetric or asymmetric. It all depends on where the ridge of the roof system of the attic floor is located.
The pediments are usually straight and simple, the room inside has the shape of a square or trapezoid. The height of the walls in the attic is about one and a half meters, then there is a conical beveled ceiling. But this design has one drawback - a lot of free space is lost. In other words, with roof slopes you cut off a very large fraction of the free space. But if you consider that before installing the attic you did not have anything in the attic, then this flaw is, frankly, dubious. In the figures in the article are drawings of the construction of a gable roof.
Broken constructions
If you look closely, it turns out that a sloping roof with an attic rafter system is one of the types of gable structures. But one slope she has at least two parts, which are located at different angles with respect to the ceilings. With this design, you will get a spacious room in the attic, which in area will not be inferior to a full floor. The ceilings in height will be the same around the entire perimeter - about 2.2 m. The area of the attic floor will be less than the first by about 15%. And this is relatively little.
In the manufacture of such a structure, it is necessary to build a very complex rafter system. A sloping mansard roof needs careful calculations. A novice master is unlikely to cope with this task. But, despite this, broken roofs are common in the construction of houses. After all, you can always find a specialist who is engaged in the manufacture of roofing systems.
Attic four-sloped hip roof
This roof is the most complex, since it uses a very "cunning" rafter system. When planning, it is necessary to make all the calculations very finely. The roofing surface has a fairly large area, so you have to spend money on waterproofing, vapor barrier, insulation. At the attic, of course, a very large part of the area is cut off. But still it will turn out to be very spacious due to the large size of the rafter system of the attic roof.
A huge plus of such a roof is its high resistance to wind and snow. Overhangs can be made large, they will protect the walls of the house from the negative effects of rainfall. The appearance of such attics is very attractive. But it is worth noting that during the construction of four-girder rafter systems, it is necessary to strengthen inclined beams. After all, it is precisely on them that the maximum load acts.
The design of the rafter system
When you make a mansard roof, make a rafter system from components of a hanging or inclined type. In the case of an inclined version, it is necessary to install the rafters so that they form a triangle, in which the faces are equal. The support must be done directly on the Mauerlat. You fix it around the entire perimeter of the walls of the first floor. In this case, one of the reference points is the connection of two bars near the ridge.
When rafters of a hanging type are installed, additional beams for supports are not provided. All structures are installed directly on the walls of the house. Puffs are allowed. At the same time, rafters work both on compression and on bending. When erecting the attic, it is necessary to create a high-quality rafter system. This is the primary task that must be solved correctly. First you need to correctly calculate and take into account all the nuances of construction. Let's determine what the basic elements are in the system.
The main components of the rafter system
There are a lot of these elements. To name some main or most important language does not turn, they all affect the work of the structure. So, let's list all the components:
- Mauerlat - this is a board or bar, with the help of which the roof system is fixed on the end of the wall of the house. It is on this beam that the rafters are fastened. Mauerlat acts as a support, transfers the maximum load from the roofing system to the wall of the structure.
- Racks are any vertically located beams that are a support for rafters. A series of beams, which are laid in the horizontal plane, and form the floor of the floor, they are also called ceilings. It is worth noting that they serve as the ceiling for the first floor of the house. With your own hands, the attic roof rafter system is easy to install, but adhere to the recommendations that we give in the article.
- Wooden beams located horizontally and performing additional reinforcement are called crossbars. They are also supporting components for rafters. Sometimes they are called puffs.
- "Rafter legs" are sometimes called simply rafters. With their help, the roof frame is made, the final shape is given.
- Moisture-proof material, lathing and coating are attached to the rafters on top. Lathing is a large number of sheets of plywood or beams that are attached directly to the rafters. Roofing material is mounted on these elements.
- A board is installed under the puff or bolt to help distribute the load. It is called a suspension.
- The board, with the help of which the roof overhang is formed, fixed on the lower part of the rafter legs, is called a filly.
As you can see, the design of the attic rafter system is not very complicated. But let's move on to the most important stage - calculation and design.
Calculation of the attic floor parameters
And now about how the calculation of the attic roof of the house is performed. Calculation of the rafter system also needs to be performed at the preparation stage. In order to prevent errors in the manufacture of the attic floor, preliminary calculations must be made. They depend on what type of rafter system and roof is used. If you wish, you can use special programs, but if there are none, do all the calculations yourself.
You need to correctly determine the area of the final roof structure, the width of the ceilings, the size of the attic floor. The calculation must be carried out based on the following parameters:
- The width and length of the apartment building.
- The amount of precipitation falling in the summer and winter. Using these parameters, you can identify the required angle of the roof.
- The width of the joints between the components of the floors.
Let's look at an example that shows a practical calculation of the attic elements. Suppose a house has a width of 3 m and a length of 12 m. If there is quite a lot of rainfall in your area, you need to make a roof slope of the order of 40 degrees. The calculation must be done according to the formula:
Hk = L x tgA.
Hk is the required height of the building, L is half the width of the building. And the last parameter is the slope of the roof. After calculating, we get a height of 1.26 m. This means that the roof should have a maximum height of no more than this value. Very often during the construction of the attic roof, the owners choose broken rafter systems for the manufacture of. Mansard roofs of this design look attractive and can achieve less loss of usable area.
Step-by-step installation guide for rafters
And now let's look at how to make a rafter system of an attic roof. There are several steps:
- First, it is necessary to lay a waterproofing material on the end of the walls. An ideal roofing material is ideal for this purpose. If there is no desire to use it, then processing with bituminous mastic or similar means is allowed. If you use roofing material, it is necessary that its width is the same as the end part of the building. If necessary, cut off excess material.
- Then it is necessary to lay the board on the roofing material. It is she who will serve you as a Mauerlat. It needs to be aligned on the inner edge of the wall end. In this board you need to drill holes that are necessary for fastening. Holes are also drilled in the wall, and anchor bolts are installed in them. With the help of such fasteners, a Mauerlat is installed around the perimeter of the house. The same actions must be carried out in the manufacture of the rafter system of the attic gable roof.
- Next, you need to fix the board on the wall with 130 x 10 mm anchors. Be sure to use an extra wide washer, in which case you will provide a large pressing area of the material. The nut on the anchor is tightened with a wrench. Try not to pull, otherwise the wood may burst.
- You make floor beams. They are made of three bars, the size of which is 200 x 50 mm. They are connected to each other using self-tapping screws.
- Connect all the boards, you need to evenly lay them on the spans between the opposite walls of your house. The distance between the floor beams should be about 40 cm. To fix the lags on the Mauerlat, metal corners are required. Perforation must be present in them. It is advisable to use self-tapping screws with a length of 90 mm. Only they are able to provide a quality connection. The article shows the scheme of roof systems of attic roofs, focus on them during installation.
- Now the installation of the truss structure begins directly. It is necessary to install boards on temporary jibs with a support. They will form the future perimeter of the entire attic floor. Boards must be level. Otherwise, you will get a curved roof.
- Now you need to make the jib. The first is mounted first, it is fixed on previously installed boards and callouts. As fasteners, metal plates and self-tapping screws are used. Then, on the first jib, you need to make a template. It is on it that the remaining elements are made in the required quantity.
- The remaining jibs must be installed in their intended places. Fixation of elements is carried out in the same way as in the previous step. The device of the rafter system of the attic roof is simple, but you need to produce all the elements, focusing on a pre-prepared plan.
- Then, vapor barrier material is laid on mounted jibs. It must be fixed with the help of bars 50 x 50 mm.
- On top of these bars it is necessary to carry out a counter-grill. It is on her consequence that you will mount the roofing material. The counter-lattice is made of boards, fixed on the previously nailed crate.
- Now you can form a horse. To prevent the boards from bending on the ceiling, you need to install temporary supports. With such elements it is much easier to work. It is necessary to lay several boards on the boards, on which you will move freely during installation.
- Now you can install the ridge beam at the required height.
- In advance, it is necessary to file the rafters and install them on one side of the already assembled roof structure with jibs, and the second on the skate beam. On opposite edges of the roof rafters, it is necessary to dock with each other directly above the ridge beam.
- Similarly, as in steps 9 and 10, it is necessary to lay the vapor barrier layer, pin the crate. But all this is done on established rafter legs. Do not forget that they must be securely fastened. Only after fastening is vapor barrier performed.
- Similarly, it is necessary to make a counter-lattice on the rafter system of the attic house.
- Make the front part of the roof of the attic. It is necessary to set the removal of wood at right angles to the logs. The length should be about 50 cm. Fixation is made using metal corners and screws to Mauerlat and logs.
- It is necessary that the stem have the same length. Therefore, if necessary, boards can be filed to the desired size.
- The racks are being installed. They need to be fixed from the bottom to the installed outriggers using self-tapping screws. From above they are fixed on metal plates. If there is a skylight in the project, then it must be formed at this stage.
- Then you need to install on the overhang of the roof of the bars, which connect the individual elements of the crate.
- Treat the roof with a topcoat. This can be slate, metal, professional sheet and other materials.
We reduce the load on the foundation
, , . . . .
:
- , . 70 . .
- — .
- , .
- .
- .
- .
- .
, . , , . , . .
Basic installation rules
, , , . .
:
- . , , .
- , , . , .
- , , .
- Rafter legs should have a cross section over 100 x 100 mm.
- Be sure to make high-quality waterproofing of the roof. Only in this case you will get reliable protection from snow and rain.
To understand which roof you need, you need to pay attention to all aspects of the work. Read the examples and drawings in advance. Of course, you can make any adjustments to your project. But be aware that revisions are allowed if they do not affect the strength of the whole structure. Now you know all the subtleties that are necessary in the manufacture of a rafter system with a do-it-yourself gable roof. Only following all the recommendations, you can make a quality roof.