I am Mikhail, director of the company, I have been working exclusively with roofs for more than 15 years. Below I will tell you about the intricacies and secrets of roofing materials. If you have any questions, I will be happy to answer and help.
Mikhail, STM-Stroy LLC
The round roof itself is not that uncommon. Most architectural monuments for religious purposes are round roofs: the onions of Russian churches, the domes of Muslim temples. The exception is Catholic Gothic. In Western Europe, domes usually crown secular buildings.
A dome is a common roof option for urban buildings based on individual projects, scientific buildings - observatories, etc. Only in country villages are houses with a round roof rare. The reason is the complex installation of the rafter system. How to make a round roof?
What is a round roof?
Calling the roof round is incorrect. It's not completely round. This group includes any roofs whose shape is a figure of rotation or one of its segments:
- Dome (half or upper third of the ball);
- Cone-shaped roofs;
- Onion roofs;
- Curved roofs with complex geometry that do not have their own name.
The rafter system for all these types of roofs is manufactured differently.
Design of a round roof truss system
note
Rafter systems for round roofs are usually layered. This implies the presence of additional supports for the rafters inside the structure.Support points:
- Ring Mauerlat;
- Ring purlin at the top of the roof. If the roof is high (above two meters), there may be more than one purlin;
- Central pillar. For small structures one is enough;
- Additional reinforcing elements (struts, ties).
The rafters themselves:
- For bulbs - rounded (metal trusses are often used instead of wood).
- For domes - rounded arched, composed of several parts. The exception is the so-called geodesic dome, popular in Western countries: it is assembled from many small triangular wooden sections.
- Cone - the rafter legs are straight, supported by round ring purlins and a round mauerlat. The ridge unit at the top is mounted similarly to hip roofs.
The installation procedure for the system is generally similar to that of conventional roofs:
- Laying an insulating layer of roofing felt on the wall.
- Installation of the Mauerlat. For example, a beam is 15 by 15 (the cross-section must be indicated in the roof design). Fix the Mauerlat to the wall with anchor bolts.
- If the entire building is wooden, the mauerlat is not installed. The rafters rest on the upper crown and are secured with galvanized nails.
- The upper annular purlin is mounted on the beam for the support post.
- Place a support post in the center of the ceiling. Reinforce with struts approximately 4 cm thick.
- The rafters are installed in increments of 50-90 centimeters, depending on the project. They are fixed to the mauerlat and purlin with construction corners.
note
The general requirement for the installation of the rafter system of any roof is to pre-treat all elements with a fire retardant and antiseptics.Our works
Round roof installation
After installing the rafters, the roofing pie is installed - the same as for other pitched roofs:
- Counter-lattice + sheathing.
You can limit yourself to waterproofing alone (without vapor barrier and insulation) if the roof is cold. But it is quite possible to create a warm attic in the dome; there is enough space there. Or your own observatory.
The roofing of round roofs can be made of different materials:
- thin sheet steel (including seam roofs);
- with some restrictions - ;
- wooden piece coverings - shingles, shingles, etc.;
- polycarbonate
Laying of any of these materials is carried out in accordance with the instructions.
If you are planning to make a roof from stacked wooden tiles, do not forget to treat them with all the necessary protective compounds and waterproof varnish.
Articles on the topic
Features of a round polycarbonate roof
Polycarbonate stands apart among roofing materials. Roofs from it are often made for greenhouses, greenhouses, gazebos, and winter gardens. In any case, these are transparent or translucent roofs; they do not have a roofing pie.
But polycarbonate itself has low thermal conductivity. The structure is not completely cold, even in the absence of insulation.
When installing, you need to take into account the characteristics of the material:
- Holes for fasteners should be drilled in advance. When drilling and cutting, be careful and avoid vibration of the sheets, as the material is prone to cracking.
- An electric jigsaw or a circular saw with a fine tooth is suitable for cutting sheets. The speed is medium: at low speed chips appear, at high speed it can lead to melting of the material.
- If moisture accumulates inside the sheets, blow them out with compressed air (for example, using a vacuum cleaner).
- Polycarbonate is subject to thermal expansion. The mounting holes should be made a couple of millimeters larger than the diameter of the screw rod.
- The ends of the polycarbonate sheet blanks must be glued with waterproof aluminum tape before installation.
- To install a polycarbonate roof, metal arched profiles are used. Installation is carried out along a radius. The frame is built up gradually as the sheets themselves are attached.
- unusual and attractive appearance;
- ease of maintenance of the structure;
- long service life.
- complex calculations for its construction;
- problems with repairs;
- high price;
- difficulty of installation;
- a large number of materials for roofing.
- dome;
- church-onion.
- loads acting on the rafter system;
- fixation of arches on the central support and ventilation lantern;
- top of the dome part;
- locking hinge, at the top of the dome;
- appearance of ventilation holes.
- connector - to connect triangles, pieces of timber and special fasteners are used;
- connectorless - all triangles are assembled in advance, and the overall structure is assembled on the roof.
- the possibility of its full glazing;
- ease of snow removal;
- excellent resistance to wind threats;
- originality of appearance;
- the possibility of organizing your own greenhouse on the roof of the house.
- High strength and load-bearing capacity;
- High resistance to strong winds;
- Snow does not accumulate on the surface of such a roof and rainwater does not stagnate;
- Larger volume of internal usable space and ceiling height in the residential attic;
- Elements of an arched rafter system (especially if they are made in the form of trusses) can become an effective decorative element of the interior decoration of the attic.
- The main load is borne by the “gable truss”. In this truss, the outer radius edge is made of “frames”. “Frames” are made of short lamellas assembled in two layers and fastened together with screws.
- Horizontal “stringers” are laid between the gable trusses, running from the upper edge of the vertical wall to the roof ridge.
- In the spaces between the stringers there are spacers made of lamellas. These lamellas have an outer radius that matches the radius of the roof.
- from above - on a circular girder made of timber, which in turn rests on the central support with braces;
- from below - on the Mauerlat in the shape of a ring.
Do you want your home to look like a medieval castle or palace? Design a conical roof. This option makes the building fabulous and solemn. Learn about the secrets of installing a conical roof truss system and get valuable advice from specialists in its repair.
Advantages of constructing a conical roof
A conical roof is installed in round buildings. Among the advantages we note:
Disadvantages of roofing with circular sheathing:
A conical roof is installed over a structure of a round or multifaceted shape. The rafter system is installed in such a way as to ensure a uniform slope of the rafters. Additional elements in the form of purlins serve as supporting elements. The upper, annular part of the purlin is fixed on the central pillars and takes on the load from the tower. The second support point is a ring Mauerlat installed on the wall of the tower. Ceiling beams are designed in such a way as to distribute the load evenly at the location where the central support element is installed.
The ring girder is fixed with braces. High-quality circular roofing requires careful calculations of each component of the system. If you do not have experience in carrying out this type of work, we recommend that you contact specialists in the preparation of project documentation.
If the rafter system is made of wood, then use laminated veneer lumber for these purposes. Especially if the roofing is finished with natural tiles. The lathing under it must be highly durable and powerful.
The conical roof is finished with bituminous shingles, wood shingles or metal. The use of wavy materials on a round roof is impractical. Joining the material will take a long time and will require increased costs. In addition, the aesthetic appeal of the roof is reduced and water flows between the joints.
Types and design of conical roof
We offer you to familiarize yourself with two options for round roofing:
A dome roof, unlike a cone roof, does not have layered rafter elements. The rafter system in a domed roof is suspended. The hanging parts form a three-hinged arch, which is connected on one side to the Mauerlat, and on the other to the support ring installed on top.
To design a domed roof, you must have enormous experience and technical knowledge of “Theory of Mechanics” and “Sopromat”. Otherwise, we recommend contacting construction companies dealing with similar issues; they will help you correctly draw up drawings of the circular roof sheathing.
To calculate a domed roof made of wood, follow these steps:
A semicircular design can be achieved by making a ring sheathing. It is installed on additional racks resting on hanging rafter arches.
Another method of installing a dome roof was proposed by R. B. Fuller, an architect from America. The design is formed using triangles. This dome is called “geodesic”. The complexity of calculations in organizing such a roof and its unusual appearance have not made it popular in architecture.
There are two ways to fix the dome using the “geodesic” system:
Among the advantages of such a roof we note:
The maximum internal volume of a geodesic roof allows you to make identical rectangular structures and increases the amount of light and air in the room. In summer, heat is absorbed by the roof, and in winter, on the contrary, it is dissipated. This reduces space heating and cooling costs. A geodesic dome does not require an expensive foundation due to its lightness. The dome structure is highly resistant to wind and weather conditions. Also, we note the excellent soundproofing characteristics of the structure, due to its extraordinary shape.
The onion roof is most often installed on Orthodox temples and churches. In private housing construction, this roofing option is less popular. If the dome diameter is less than 300 cm, its frame part is made of wood.
The specific shape of this roof is called “crane”. This version of the rafter system is called layered. To give additional rigidity to the roof, elements are installed in the form of braces and struts. They take on the maximum load. To cut out the crane, special patterns and boards are made, the minimum thickness of which is 40 mm. The central pillar serves as a support for the “cranes” and as a place for mounting the cross on the dome.
If metal is used for further finishing of the dome, then the crate is mounted on the cranes in increments of 30 cm. It is possible to finish the dome using a scaly roof. In this case, an additional element for fastening it is installed under each scale.
When restoring a church dome, it is covered with an aspen ploughshare. They are mounted in such a way as to prevent moisture from entering between the rows. Domes of this type are characterized by the complexity of design and installation. Only professionals can perform high-quality work. If the diameter of the dome is more than 300 cm, then steel is used for its frame. To fix the cranes in this case, metal spacers are used. The sheathing is made of steel strips installed in increments of 40-50 cm. Seam metal is used to finish the roof.
Conical roof construction technology
We offer the option of creating small cone-shaped towers adjacent to the house. Such a roof is not the main one, but its design requires special knowledge. The rafter system in small towers is installed in a fan-shape. The common central post is where the rafter legs diverge. An additional supporting function is performed by purlins; laminated wood is used for their manufacture. There are two options for purlins - upper and lower. Each of them performs the function of uniformly distributing the load. After developing the conical roof design, the wheels are made. The ends of the rafters are fixed on a semicircle, thus increasing the strength of all connections.
For additional stability of the roof, the lower plane of the rafters is sawn at a certain angle. Use steel angles to secure wooden parts.
When calculating the number of rafter legs for a cone-shaped roof, take into account such points as the cross-section of the material from which they are made and the interval of their installation. On the underside of the roof, the spacing between rafters should be minimal. Thus, the lathing for further finishing of the roof will be made with the smoothest possible bend. To do this, an additional spacer with a smaller cross-section is placed in the lower part between the main beam; it will make the surface more durable and neat.
Next, install the drainage gutter. Their semicircular versions are made exclusively to order. To assemble the system yourself, it is enough to use small sections of ordinary straight gutters, connecting them at the desired angle. All connections must be tight and neat.
Take care of the sheathing, which is most often created using wooden beams, flexible plastic parts or ordinary water pipes. The load-bearing capacity of the latter elements is only suitable for supporting a small-sized roof used as decoration, but not for the main domed roof. For additional strength, fold the pipes or beams in half. To fix them on the rafter system, use self-tapping screws.
The cone-shaped roof is finished using the seam method. The tiles are laid on the surface of shingles or reeds. When finishing the roof with tiles, take into account the fact that the width of the tiles increases from top to bottom. Therefore, choose special versions of conical tiles to avoid sloppy joints. Calculate the length of the rafter elements, the total area of the roof, and based on this, purchase the required amount of finishing materials.
Install trim from bottom to top. Each tile is installed with a slight overlap in relation to the side and underlying ones. At the junction of the roof and the outer wall, install waterproofing.
Check out the features of constructing a conical roof:
1. The slopes are brought to the roof surface at least thirty centimeters.
2. A standard beam is installed on a regular concrete floor, and the rafter system is fixed on it.
3. For a tighter connection of the end sections of the rafters, we recommend sharpening them.
4. The upper parts of the rafters are installed on a semicircular support and connected to each other using steel corners.
5. The sheathing is made of semicircular bars: long and short elements.
7. Before tiling, secure the drainage systems.
8. The installation interval of the sheathing is determined by the type of roofing finishing material.
9. Using tapered tiles, pre-label the elements of each row. Reduce the amount of material for each individual row.
Flexible or bituminous shingles are installed on a solid base. For these purposes, thin-sheet plywood is most often used. To create a thermal roof, additional insulation, vapor barrier and waterproofing are installed.
The plywood is cut into a trapezoidal shape and laid from bottom to top. The thickness of the layers of plywood covering should be at least 12 cm. That is, using 4 mm plywood, lay it on the base in 4 layers. Next, moisture protection and bitumen shingles are installed.
A steel ridge is installed on the top of the cone-shaped roof. For its manufacture, steel, copper, aluminum, and stainless steel are used. Additionally, if necessary, install a weather vane.
When choosing a tool for constructing a conical roof, you need to take into account the materials used for the sheathing and roof finishing. At the same time, if the sheathing is mounted from wood, then you will definitely need a jigsaw, a hammer drill, and a screwdriver. When using steel materials, stock up on a grinder with cutting discs, metal drills and an electric drill.
Video on installing a conical roof:
The variety of roofing structures that are used today to cover private houses makes it possible to choose the best option in terms of performance characteristics and price of the structure. In this article we will talk about the rabbit, which is not often found in Russian open spaces. This is a round roof. Let's consider what forms it comes in, what elements it is built from, and also tell you about the technology of its construction.
Types of round roofing structure
From a purely constructive point of view, the round roof should be divided into three types:
hemisphere, also known as geodetic view;
arched type;
cone-shaped.
It should be noted that each type has its own advantages over others, as well as construction technology. Therefore, we will consider each position separately.
Geodesic roof
This type of roofing structure was developed in 1951 by the American architect Fuller. The engineer found a way to create a roof that did not have a traditional rafter system. Instead, the basis was a frame assembled from equilateral triangles. The latter, in turn, were assembled from timber with a cross-section of 50x100 mm and a length of 1-1.2 m.
They were connected to each other by a special connecting element called a connector. Essentially, it is a steel pipe with a diameter of 100 mm and a length of 6-8 cm. Metal blades 60 mm wide and 150 mm long were welded to it, which overall formed a five- or six-pointed star. The blades were welded in pairs. The photo below shows such a connector.
That is, during assembly it turned out that equilateral triangles were formed by installing their elements between the paired blades of the connectors. Where they were fastened with self-tapping screws on the side of each blade.
Today, manufacturers of hemispherical roofs offer not only connecting elements of this type. There are other designs. In addition, it should be noted that Fuller roofs today are assembled using a technology in which there is no place for connectors.
The assembly process for this type of roof begins like all roofing structures. Namely, from installing the Mauerlat. It is clear that a round roof structure can only be installed on a round house. And here there is one subtle point on which the quality of the final result depends. Namely, the method of mounting the Mauerlat.
To do this, a beam with a cross-section of 50x100 or 100x100 mm is cut into segments with a length equal to the length of the equilateral triangles from which the roof frame is formed. After which these pieces of lumber are mounted either on the walls of the house or behind the poured foundation. The fastening method is chosen as standard, but more often it is vertically installed studs, which are built into the reinforcing belt of the house or foundation.
After the Mauerlat is installed and secured, they proceed to assembling the roof frame. To do this, L-shaped steel plates are installed and secured with self-tapping screws along the edges of the Mauerlat elements. The edges of triangles located at an angle to the horizontal are attached to them. A connector is installed in the upper part of the two ribs. That is, it turns out that a section of the Mauerlat in the lowest plane of the roof frame assembly performs the functions of one of the edges of equilateral triangles.
After that, one additional edge is mounted horizontally between the vertices of the formed triangles. First, these ribs form a horizontal reference plane. Secondly, they form triangles that are located upside down. Then the whole process is repeated. That is, a second row of two differently directed triangles is formed.
It should be noted that in the design of geodesic type roofs there is no such element as a ridge or its like. The point is that the roofing structure smoothly transitions into a hemisphere, forming at the very top a rounded shape consisting of an equilateral triangle or hexagon.
As soon as the hemispherical roof is assembled, they proceed to its further formation. Today, structures of this type are covered with flexible roofing materials, for example, bitumen shingles. Therefore, a continuous sheathing of OSB boards, which are cut in the form of equilateral triangles, is laid under it. The main requirement is to leave a gap of 1 cm between the cut slabs, which compensates for the moisture expansion of the material.
And one last thing. This is the insulation of geodetic roofs. Everything here is the same as in pitched roofs. The same materials and technologies are used. That is, a thermal insulation material is placed inside the triangles, which is cut to fit the shape of the roof frame element.
As mentioned above, such a roof can be assembled either on the erected walls of a round house or on the foundation. The latter option is very popular today, especially in Europe. There is an opportunity to save a lot of money. At the same time, the hemisphere copes well with all loads.
On our website you can get acquainted with the most from the manufacturers presented at the exhibition of houses “Low-Rise Country”. The presence of filters and an online calculator allow you to make a preliminary calculation of the total cost of the house.
Arched roof
Note that roofs of this type are similar in purely design features to pitched roofs. That is, they have a rafter system. True, these are not linear type beams or boards. These are arched elements, which are presented in two types on the market:
from laminated veneer lumber;
from steel profile.
The first are thin boards that are kept in water and then bent to the required bending radius. In this curved form, the boards undergo forced drying, forming an arched element. After that, several boards are glued together, forming laminated veneer lumber. This is a very durable product, but not very cheap. As for the second position, these are, in fact, standard trusses made of metal profiles (pipe, angle, channel). This option is usually used if the span of the roof structure exceeds 5 m.
The process of assembling an arched dome roof from ready-made elements involves installing rafters so that their lower ends rest against the mauerlat and are secured to it. And the top ones at the top point of the roof rested against each other. This is where they consolidated their positions among themselves.
There is another option for assembling an arched dome roof. To do this, boards with a cross section of 50x100 mm of short length are used, from which arc-shaped rafters are formed. They are connected to each other by perforated metal plates using self-tapping screws. At the same time, pieces of boards are laid so as to form an arc. The photo below shows one of these assembly options.
On our website you can find contacts of construction companies that offer. You can communicate directly with representatives by visiting the “Low-Rise Country” exhibition of houses.
Cone roof
This type of dome roof roofing structure can be used both as a separate unit and as an integral part of a complex roof. But under one condition - the base for the structure must be round.
In a conical roof, straight-type rafter legs are used. But all other elements of pitched roofs are missing here, namely: ridge, gables, valleys and others. This makes it possible to create a sloping plane on which a large amount of snow never accumulates. But this often becomes a mistake in the process of designing cone roofs.
That is, some customers do not pay attention to the height of the roof. But you can’t make them flat. Here the minimum angle of inclination should not be less than 15°. And most often such roofs are made into attics, that is, non-residential. To withstand the loads, a support post made of exactly the same board as the rafter leg is installed under each rafter. The stand rests either on the ceiling beam or on the reinforced concrete floor of the building.
If it is intended to organize a serviced room under the roof, then the formation of the rafter system is approached differently. Firstly, for this purpose a roof structure is created with an angle of inclination in the range of 70-75°. Secondly, spacers made of boards or beams are installed between the rafters, which increase the rigidity of the structure. Spacers are installed not in each rafter space, but through one leg. For example, if there are 10 rafters in a conical roof structure, then there should be 5 struts. The sheathing will add additional rigidity to the roof.
That is, in the second option there are no racks and supports that take up a lot of space. But it is also necessary to highlight the fact that a steep roof with a large angle of inclination along its plane is practically not loaded. The main loads fall on the upper part of the structure. Therefore, the rafters at the top point are well connected to each other using long screws and additional fastening devices.
Video description
The video shows how a conical roof frame is constructed:
Type of houses with round roofs
The main requirement for the construction of domed roofs is a geometrically correct base. And here there are two options: round or square base. If the shape of the walls of the house is a rectangle, then you shouldn’t even think about erecting a dome-type roofing structure. There is another option - a semicircular arched roof.
If the foundation of a private house is a complex structure. Or during the construction process changes were made to it, for example, new premises were completed, then in this case it is better to use a combined roof. That is, one that uses pitched and dome structures.
As for the loads from the roof on the walls and foundation, here, as in the case of other types of roofing structures, it is necessary to correlate the types of materials used to construct the walls and roof. For example, you cannot install metal profile trusses on wooden walls assembled using frame technology. If the house is built from stone, blocks or bricks, then the restrictions are reduced, and in many cases completely eliminated.
Advantages of dome roofs
In fact, dome-type roofs have very serious advantages:
attic space can be used to the maximum, with almost one hundred percent efficiency;
on domed roofs can be installed unlimited number of windows, there are even transparent designs, fully glass covered;
the round configuration prevents snow from catching on the roof plane, which reduces loads from natural precipitation to zero;
low weight of the structure due to fewer elements and parts used;
dome-type roof at times stronger And more reliable any pitched varieties;
unique appearance, which is different from all other roofing structures.
Video description
In the video, the owner of a round house covered with a round roof explains how he built this original structure:
Conclusion on the topic
Round roofs, taking into account their advantages, are gradually conquering the Russian construction market today. Not all country developers give them preference, but such roofing structures are appearing more and more often. In addition, domed roofs make it possible to build houses without walls. And this is a big saving.
The most common forms of roofs for cottages are “hip” and “double-pitched”. This is explained by the fact that this roof shape is well known to many builders, and all stages of manufacturing are described in detail in any methodological publication.
However, many private developers would like to move away from the “clichés”. There is a growing interest in domed, semicircular and pointed roof shapes. In addition to its attractive appearance, such a roof has a number of significant advantages:
Thinking about how to make a semicircular roof from wood, and understanding the many advantages of a “bent” roof, many developers are put off by the high price of an arched rafter system, the complexity of its calculation and manufacture: in industrial conditions, lamellas (from which laminated veneer lumber is made), steamed to 100 °C, at high humidity (which gives the wood elasticity) they are bent according to a special template, then glued together and dried in drying chambers.
Along the bend line of the beam, you can make special cuts - “to a cone” or “to a rectangle”. This simplifies the process of bending wood.
In private construction conditions, such a technological stage is difficult and economically unfeasible to repeat. And when using industrially manufactured parts - in the form of bent laminated veneer lumber, steel and wooden curved trusses, etc. – the cost of such a rafter system increases many times over. Therefore, FORUMHOUSE users offer their own, more “budget” methods for making arched rafters and semicircular roof rafters.
Nikofar User FORUMHOUSE, Moscow
I decided to build a frame outbuilding with a semicircular pointed roof. To do this, I had to become one person: an architect, a designer, a customer, an estimator, a “sponsor” of construction, a foreman, a technical supervision specialist and a builder. But the result was worth it. I managed to realize all my ideas. And for several hundred thousand rubles (260 thousand of which were spent purely on the “frame”) to build a house with a “pointed roof”, 3 bedrooms, a kitchen-living room, an entrance hall, a separate bathroom and a small hall on the second floor.
What the forum member ended up with can be seen in this photo.
Of particular interest are the stages of manufacturing a “bent” rafter system.
In the classical sense, this “rafter” does not have the usual rafter legs.
There are also no glued elements in it. If you look at the photographs, you can say that the rafter system uses elements borrowed from shipbuilding.
The essence of the technology used Nikofar is as follows:
The slats were cut out with a chainsaw. To simplify and speed up the marking of lamellas, a special template was made - a semicircle of two slats and plywood 12 mm thick.
Such a template is cut to a specific and pre-calculated radius of curvature of the roof. Also, before you start making a curved rafter system, you need to make a full-size radius template. Check at the installation site whether the required radius is observed, whether everything is calculated correctly, and only after that proceed to the manufacture of the remaining rafter legs. This will allow you to avoid defects, as well as timely make appropriate adjustments to the dimensions of the rafter system and template.
If you get the hang of it, it took the workers about 3 minutes to make one “radius” lamella, including marking and selecting the right board.
After the construction of the rafter system was completed, sheathing was installed along the roof frame. For the sheathing (to save money), instead of plywood or OSB, a second-grade edged board was used - 10x2.5 cm. The pitch between the boards was 5 cm. Then the roofing covering made of ondulin was installed.
The proposed method of making “bent” rafters and the process of constructing an inexpensive frame house for permanent residence found a wide response on the forum. Forum members also expressed their pros and cons of the economic feasibility of erecting such a pointed roof. They also talked about the excessive consumption of wood. Let's see how true this is:
Thanks to the arched section pointed roof, with comparable costs for lumber, internal useful the volume of such a residential attic under the arch is greater than an attic of a traditional design, as well as an attic with increased overhangs.
Nikofar drew all the above drawings not in a specialized graphics program, but using the “old” MS-paint.
The arched roof, due to its shape, can withstand very heavy loads, which the builders of antiquity knew well.
Also of great interest is the project of a house with a semicircular roof from a member of our forum crazy-tortilla.
crazy-tortilla User FORUMHOUSE
I want to build a house with a semicircular roof. According to the project, it is necessary to block an unsupported span of 11x8 meters. I'm thinking of using wooden I-beams for this. Then make OSB flooring on top and lay a soft roof. There will be no attic. Help me to understand, how to make a semicircular roof out of wood.
To prepare the base for laying flexible tiles on a radius roof, you can use moisture-resistant plywood or OSB boards up to 9 mm thick. Plates of this thickness are bent “in place” without the use of special devices. To obtain the required thickness of the base, slab material of small thickness (6 mm) can be laid in two layers, with the seams of the bottom layer overlapping the top layer.
After brainstorming on the forum and arguing about the type of construction of the truss system for such a roof, a decision was made: instead of horizontal I-beams, use a bent laminated wood truss. After this, the forum member ordered a farm design from the designer. The photo below shows finished drawings of these trusses.
Collect bent trusses (to save money) crazy-tortilla I decided on my own. Structurally, the farm is assembled from three layers of wood, for which 150x30 mm boards are used.
The round roof itself is not that uncommon. Most architectural monuments for religious purposes are round roofs: the onions of Russian churches, the domes of Muslim temples. The exception is Catholic Gothic. In Western Europe, domes usually crown secular buildings.
A dome is a common roof option for urban buildings based on individual projects, scientific buildings - observatories, etc. Only in country villages are houses with a round roof rare. The reason is the complex installation of the rafter system. How to make a round roof?
What is a round roof?
Calling the roof round is incorrect. It's not completely round. This group includes any roofs whose shape is a figure of rotation or one of its segments. Half dome or sphere segment.
Design of a round roof truss system
The rafter system for all these types of roofs is manufactured differently.
Rafter systems for round roofs are usually layered. This implies the presence of additional supports for the rafters inside the structure.
Dome roof.
A strong and reliable domed roof has an important advantage, characteristic of all round structures - it has excellent air flow.
Another plus, important for our climatic conditions, is that snow does not linger on it at all.
The structure of the dome involves the use of hanging rafters in the shape of arches. Technically, this is a complex decision, so all calculations must be made by specialists in this field.
A vertical support pillar is installed in the center of the structure, onto which a ring is attached - the upper support for the rafters. At the bottom, the arched elements are fixed on the Mauerlat.
The ring sheathing is attached to racks that rest against the rafters, and the roofing covering is already laid on it.
The dome can be both the roof and the walls of the second floor.
A dome formed from triangles is known as a geodesic dome. Its highlight is the possibility of full glazing.
But despite its advantages, the design has not become widespread due to the complexity of the calculations.
Conical (cone-shaped) roof.
The rafter system is used as a layered type. A support - a pillar - should be located in the center of the building.
The rafter legs rest on:
The rafters are rigidly attached to the supports using corners. The distance between them depends on the cross-section and the expected load - the weight of the roofing material. The lathing is circular.
SO THE CHOICE IS YOURS!!!
