Posted by Profiled sheets made of galvanized steel have proven themselves as a reliable roofing material. Their widespread use is justified by a number of significant advantages over other types of roofing. We will dwell in detail on the strengths and weaknesses of profiled sheets, identify its key characteristics and discuss the use of these sheets for the installation of a single-pitched garage roof.
Pros and cons of corrugated sheets
Let’s first consider the positive aspects of this building material:
- Visual appeal. Modern corrugated sheets are available in a variety of colors and imitations of natural textures, including wood and stone.
- Economic benefit. Compared to other roofing materials, corrugated sheets are more affordable.
- Durability. Products made of corrugated sheets treated with polymer coatings can last up to 50 years with a minimum service life of about 25 years.
- Lightweight construction. The low weight of corrugated sheets facilitates roof construction, reducing the load on the rafter system.
- Easy to install. Installation of corrugated sheets does not require the use of specialized equipment and can be done manually.
- Ease of processing. Profiled sheets can be easily cut and processed, including making the necessary holes.
- Size range. Availability of sheets of different lengths (from 0.5 to 13 m) allows to reduce the number of joints on the roof, reducing the likelihood of leaks.
- Multifunctionality. Profiled sheeting is suitable for roofs with any slope angle.
- Resistance to climatic conditions. The material can withstand various weather loads.
- Environmental safety. The corrugated sheeting does not contain any substances harmful to the environment.
The main disadvantage of corrugated sheets is the noise when precipitation, such as rain or hail, hits them. However, if this aspect is not critical for the owner of the building, corrugated sheets become an ideal solution for roofing work, in particular for single-pitched garage structures.
Techniques for constructing a pitched roof
The choice of construction technique for a pitched roof directly depends on the material used for the main structure of a building, such as a garage. In the case of using bricks or building blocks, there are two main ways to create a roofing system:
- Formation of a slope by constructing one wall higher than the other.
- Alignment of the height of the walls and subsequent formation of the slope using an additional frame structure made of lumber.
When constructing a rafter system, it is necessary to adhere to a certain methodology. One of the key aspects is determining the step of installing rafters, usually fluctuating between 0.8 and 1.2 m. Rafters made of boards 40–50 mm wide are used as standard, which is considered suitable for small garage buildings.
One of the common obstacles when constructing a rafter system is the insufficient length of the rafter legs. Since the standard length of the board is 6 m, it is often not enough to completely cover the garage, especially considering the angle of the rafters. It is often necessary to extend the boards in different ways, including installing additional supports under the extended rafters.
In the case of a frame garage, the roof is formed during construction. Pairs of posts of different lengths are installed at the corners of the future garage, creating a roof slope. These posts are connected by horizontal and inclined beams, determining the roof slope.
For garages made of metal profiles, the process of forming a roof is similar to frame construction: posts of different heights are installed, forming the required roof slope.
Let’s consider the process of building a roof from corrugated sheets for a garage built from blocks with uniformly high walls.
Installation of rafter structure for garage
The main stage in the construction of the rafter structure is the installation of the wall plate. For a garage, which is usually a simple structure, a board with a thickness of 50 mm or a beam with parameters of 100×100 mm is ideal. It is important that the dimensions of the wall plate correspond to the dimensions of the walls of the building. The wall plate is laid around the entire upper edge of the walls.
Attaching the mauerlat is a key step. A commonly used method is to use 4-5 mm thick wire folded in half and placed under the second row of blocks from the top of the wall, i.e. directly under the top row. The wire should be long enough to ensure a strong connection between the board and the wall and is placed at intervals of one meter.
Next, to create a roof slope, vertical posts up to a meter high are installed on one side of the garage (usually the front or side). The height of these posts determines the roof slope angle – the higher the post, the steeper the slope.
The posts are attached to the wall plate using galvanized steel corners and screws. It is necessary to ensure that the supports are installed vertically and that their upper edges are uniform. Then a horizontal board is attached to the posts, forming the upper part of the truss structure, using similar corners and screws, creating a rectangular frame on the wall.
After this, they begin installing the rafter legs, one end of which is placed on the upper strapping of the constructed truss, and the other on the wall plate on the opposite wall. The rafters are fastened with nails, long screws, wire, staples or perforated corners and plates.
The key aspect is to install the rafters in such a way that their upper edges lie on the same inclined plane, thus ensuring the correct roof slope.
When constructing a rafter system, it is recommended to adhere to the following procedure:
- Placement of end rafters: Begin by placing two rafters at either end of the structure.
- Align the rafters. To ensure that the rafters are level, use a spirit level, a taut line, or a long, straight strip to align their ends.
- Creating a sloped plane: Stretch 4-5 lines across the rafters that have already been installed to create a uniform slope.
- Installing the remaining rafters. Place the intermediate rafters according to the guidelines.
Various materials are suitable for the lathing: these can be slats with a cross-section of 40×40 or 50 x 50 mm or boards with a thickness of 25–35 mm and a width of 100 mm, with preference given to the latter option.
When it comes to building a roof from corrugated sheets, it is important to choose the right pitch of the sheathing elements, which depends on the type of corrugated sheets used. For garage structures, corrugated sheets with a wave height of 20-35 mm are best suited, under which the sheathing is laid with a pitch of 60-80 cm. The fastening of the sheathing elements to the rafter system is carried out with wood screws, the length of which is twice the thickness of the elements used for the sheathing.
Stages of installing corrugated sheets on a garage roof
Once the preparation and assembly of the single-pitched roof rafter system is complete, the next step is the correct laying and fastening of the corrugated sheet. This stage includes several key points, the observance of which guarantees the quality and durability of the roof:
- Mutual overlap of sheets. To ensure perfect tightness of the roof covering, the corrugated sheets are laid with an overlap of one wave.
- Overlapping joints in length. When corrugated sheets are laid lengthwise in several rows, their joints should also overlap by 10–30 cm. The smaller the roof slope, the larger the overlap size should be. Silicone sealant is often used to enhance the tightness of these joints.
- Use of high-quality self-tapping screws. The corrugated sheeting is attached to the lathing using special roofing screws with a rubber gasket and a hex head that is resistant to atmospheric influences.
- Correct fastening of screws. Screws should be screwed in strictly perpendicular to the sheets of corrugated sheeting to prevent water from penetrating through the gaps.
- Be careful when tightening the fasteners. It is necessary to maintain a balance of force when tightening the screws so that they securely fix the corrugated sheet without damaging it.
After installing the corrugated sheets on the garage roof, it is also important to design the gable and façade parts of the roof structure. For this, you can use the same corrugated sheets or other materials, such as building blocks, wooden boards, plywood or OSB boards, which will harmoniously fit into the overall style of the building.
Installing corrugated sheets on a flat garage roof
After completing the preparation and construction of the rafter system on the flat roof of the garage, the next step is laying the corrugated sheet. Such roofs, having an angle of inclination of up to 5°, are usually covered with roll bitumen materials, and today these are most often modern bitumen-polymer coatings that last up to 25 years. These materials, replacing traditional roofing felt, require regular maintenance and are subject to rapid wear, which encourages garage owners to choose corrugated sheeting.
To install corrugated sheets, first create a rafter system directly on the roof. There are two methods:
- Direct fastening to the floor. The rafters are attached directly to the concrete surface of the roof.
- Creating a slope using racks. In this case, the rafter system is installed on support racks, creating a slope.
The second method is a more complex and expensive process, similar to the construction of a pitched roof. The easier to implement first option involves laying 30-40 mm thick boards directly on the roof surface. The boards are fixed to the concrete using metal dowels or perforated tapes with screws inserted into plastic dowels.
Please note that in this case the boards act as a lathing, so they are placed across the roof slope and laid at a certain pitch (40–80 cm). The pitch depends on the wave height of the corrugated sheet used.
Installation is carried out in accordance with the previously described recommendations, with special emphasis on precise adherence to the instructions. On flat roofs, it is critical to use solid sheets of corrugated sheeting, avoiding joints along the roof to prevent leaks.
Sealed roofing made of corrugated sheets laid in whole sheets ensures the reliability of the entire garage structure. This material, which combines excellent performance properties and affordable cost, is becoming the preferred choice for modern garages.
Roof installation by La Roma Renovators specialists
La Roma Renovators specializes in comprehensive turnkey roof installation . Our services are in demand among customers for a number of reasons:
- Our qualified specialists cover the entire roofing process, from dismantling the old covering to installing a new one, including possible replacement of the rafter system. We are ready to offer both a comprehensive approach and the implementation of individual stages of work.
- We not only produce corrugated sheets, but also work with leading manufacturers of building materials, guaranteeing high quality and compliance with state standards. An effective pricing policy, due to the absence of intermediaries, makes our services more accessible.
- Our clients can count on high-quality and timely service, including troubleshooting joint tightness issues, correcting roof structure geometry, restoring drainage systems, and much more.
- Our craftsmen regularly improve their skills, mastering the latest technologies in the field of roofing works, which allows them to successfully cope with tasks of any complexity.
Contacting us guarantees high quality roofing work thanks to a combination of experience, professionalism and the use of modern materials.