Country property owners are often faced with the need to protect their vehicles from the scorching sun, heavy rains and snow. It becomes an excellent solution carport for 2 cars, which allows you to save site space and budget by combining parking for the whole family into one structure. Correct calculation of dimensions is not just a matter of convenience, but a necessity on which the durability of the roof and the safety of cars depend.
When designing, it is important to take into account not only the current vehicle fleet, but also possible future acquisitions, since changing to a larger vehicle can create parking problems. In this article we will analyze in detail what sizes are optimal, how to calculate the width of the spans and the height of the racks so that carport for two cars served for decades without repair.
Mistakes at the planning stage often result in cars scratching each other or pillars preventing doors from opening. To avoid such situations, it is necessary to strictly follow building codes and take into account the ergonomics of parking. Below is a detailed analysis of all aspects of the design. double carport.
Optimal dimensions and parking standards
The size of a carport for two cars directly depends on the class of vehicles that will be under it. The standard parking module for one class C or D passenger car is 2.5 meters wide and 5 meters long. Therefore, the minimum width of the structure for two cars side by side should be at least 5 meters clear between the supports.
However, simply folding two machine widths is not enough. It is necessary to provide a technological gap for opening doors and safe passage between cars. If you plan to store crossovers or minivans, it is better to increase the span width to 5.5–6 meters. This will allow two cars to fit comfortably, even if one of them has wide rear-view mirrors.
⚠️ Attention: The minimum permissible distance between the inner edges of the support posts should not be less than 5 meters. Trying to save 50–70 cm often results in the impossibility of getting out of the car without getting your clothes dirty on the dirty counter or hitting a neighboring car.
The length of the canopy is usually taken as standard - 5.5–6 meters. This is enough to accommodate most passenger cars with some room in the front and rear. If the family has pickup or a car with a trailer, it is advisable to increase the length to 7 meters so that you do not have to maneuver each time when driving.
Calculation of structure height and angle of inclination
Canopy height is a critical parameter affecting aerodynamics and snow load. For passenger cars, the minimum roof overhang height should be 2.3–2.4 meters. This ensures free passage even for vehicles with a roof rack or a roof-mounted bicycle. For SUVs and minibuses, it is better to raise the height to 2.5–2.7 meters.
The angle of inclination of the roof is selected depending on the type of covering and climatic conditions of the region. For a lean-to structure, which is the most popular for attached and free-standing sheds, an angle of 10 to 30 degrees is considered optimal. Sloping roofs (less than 10 degrees) require ideal tightness, since water drains slowly and the snow load increases.
When calculating the height of the rear wall (for a lean-to canopy), it is necessary to take into account the height difference. If the front pillar has a height of 3 meters and the length of the slope is 6 meters, then at an angle of inclination of 15% the rear wall will drop by about 90 cm, amounting to 2.1 meters. It is important to check that at the lowest point the height still allows the vehicle to enter safely.
There is a formula for approximate calculation of the height of the rear support: H_rear = H_front - (L_slope * sin(angle)). Accurate trigonometric calculations will help you avoid mistakes when purchasing materials for racks and rafter systems.
Selection of materials for frame and roof
The durability of the canopy depends on the selected frame material. The most popular solution is a profile metal pipe of square or rectangular cross-section. For racks, a pipe of 100x100 mm or 80x80 mm is usually used, and for trusses and purlins - 40x40 mm or 60x40 mm. Metal requires high-quality anti-corrosion treatment and periodic painting.
A wooden canopy looks more organic in the landscape of a country house, but requires constant maintenance. A beam with a cross section of 150x150 mm or 200x200 mm can withstand significant loads, but the wood must be impregnated with fire-retardant compounds. The service life of properly treated wood can be up to 20–25 years, but the risk of rotting at points in contact with the ground remains high.
Polycarbonate remains the leader among roofing materials for carports. Cellular polycarbonate with a thickness of 10–16 mm is light, durable and diffuses light well. Monolithic polycarbonate is stronger, but more expensive. Also often used corrugated sheet, which is highly noisy during rain, but is cheaper and more durable than plastic.
- 🚗 Profile pipe — an ideal choice for a frame: durable, not afraid of moisture (when painted), easy to install by welding or bolts.
- 🌳 Glued laminated timber - an aesthetic alternative to metal, it is less deformed by temperature changes, but requires protection from fire.
- 🏗️ Combined option - metal racks and wooden floor beams, which combines strength and beautiful appearance.
Types of foundations and installation of supports
The foundation for a canopy is the basis for its stability. Since the structure is lightweight compared to a house, a massive strip foundation is rarely required. The most common option is a columnar foundation. Under each support post, a hole is drilled to a depth below the freezing point of the soil (usually 1.0–1.2 meters), formwork is installed and concrete is poured.
Metal racks can be concreted directly into the well, after pre-treating the underground part with bitumen mastic. An alternative option is to install racks on ready-made concrete blocks or use screw piles. Screw piles allow you to erect a canopy in one day, even on difficult terrain, without excavation work.
When installing supports, it is important to strictly control the vertical. A misalignment of even 2–3 degrees can lead to a redistribution of loads on the roof and, as a result, to deformation of the structure under the weight of snow. For metal racks, ready-made embedded parts with flanges are often used, which are anchored to the concrete head.
☑️ Preparation for canopy installation
Comparison table of roofing materials
The choice of roofing material affects not only the appearance, but also the load on the foundation. Lightweight polycarbonate allows the use of thinner metal, while heavy tiles or slate require a reinforced frame.
| Material | Weight 1 m² (kg) | Service life (years) | Features |
|---|---|---|---|
| Cellular polycarbonate | 1.5 – 2.5 | 10 – 15 | Transparent, light, may turn yellow |
| Corrugated sheet (0.5 mm) | 5.0 – 6.0 | 20 – 30 | Noisy, durable, does not fade |
| Metal tiles | 4.0 – 5.0 | 20 – 40 | Aesthetic, medium weight, requires lathing |
| Ondulin | 3.0 – 3.5 | 10 – 15 | Silent, non-fading, flammable |
When choosing a material, it is worth considering the climatic factor. In southern regions, transparent polycarbonate can create a greenhouse effect, heating the car interior even in the shade. In such cases, it is better to use tinted material or an opaque roof with partial clearance.
Features of DIY construction
Building a carport for two cars with your own hands is a very real task for a home craftsman with basic welding or woodworking skills. The key stage is assembling the trusses. It is better to weld them on the ground, and then lift them and attach them to the posts. This ensures geometry accuracy and safety when working at height.
The truss installation step is usually 1 meter for light roofs (polycarbonate) and up to 1.5 meters for heavier ones. The purlins are laid across the trusses in increments of 60–80 cm. It is important to use thermal washers when attaching polycarbonate to compensate for the thermal expansion of the material and avoid cracks.
⚠️ Attention: When installing polycarbonate, do not overtighten the screws. This will lead to deformation of the sheet around the hole and loss of tightness. Use a special tool with a force limiter or control the process manually.
For timber structures, it is critical to use galvanized fasteners. Regular nails or black self-tapping screws will quickly rust, and rust will flow through the wood, spoiling the appearance. All wood cuts must be thoroughly treated with an antiseptic.
Is it necessary to drain the canopy?
Yes, drainage organization is required. Without gutters and pipes, water will flow along the perimeter of the canopy, eroding the soil at the base of the foundation and creating puddles under the wheels of cars. This can lead to subsidence of the supports and corrosion of the bottom of the machine.
Legal nuances and placement on the site
Before starting construction, you need to decide on the installation location. According to building codes (SP 53.13330), the canopy is classified as an auxiliary building. The distance from the canopy to the border of the neighboring plot should be at least 1 meter, and the roof slope should be directed in your direction so that water does not flow to the neighbor.
If the canopy is adjacent to the house, it is considered part of the building, and the distance to the property line increases to 3 meters (for fire safety). It is also important not to block public access roads with a canopy and not to shade the windows of living rooms for neighbors.
In some cases, especially if the shed has solid walls and a foundation, its area may be taken into account in the percentage of the site's development. For a light canopy (on four pillars without walls), a building permit is usually not required, but in case of disputes with neighbors or inspection authorities, having a project will be an advantage.
Leave some extra width. If you plan to park two cars, make the width the same as for three narrow spaces. This will allow you to park even if one car is parked crookedly, or if guests arrive in a large SUV.
Common design mistakes
One of the most common mistakes is saving on the cross-section of metal. Owners often place thin pipes 40x20 mm on racks 3 meters long, believing that “it will do.” However, in winter the snow cap can weigh several hundred kilograms, and such a structure risks collapsing, damaging cars.
The second mistake is the lack of cross braces (braces) between the posts. Without them, the canopy is a set of separate frames that do not have spatial rigidity. In strong winds, the structure can be shaken or even overturned. Be sure to use braces or rigid fastening of the trusses.
The third mistake is ignoring the ground level. If the area under the canopy has a slope, it is necessary to either level the ground or make a stepped foundation, otherwise one side of the canopy will be lower and rainwater will flow under the car.
The main secret of a durable canopy is not the thickness of the polycarbonate, but the correct calculation of the snow load on the trusses and a high-quality foundation that goes below the freezing depth.
Do I need to legalize a carport for two cars?
If the shed is a temporary structure (does not have a permanent foundation or walls), it usually does not require registration with Rosreestr. However, if you are building a permanent garage with a foundation that cannot be moved without destruction, it is considered real estate and requires registration. In gardening partnerships (SNT), the rules may be stricter, so it is better to consult with the chairman.
Which polycarbonate is better: cellular or monolithic?
For carports, cellular polycarbonate is preferable due to its low price and good thermal insulation properties. Monolithic polycarbonate is stronger and more transparent (like glass), but it is much more expensive and creates more heat under the canopy in the sun. A cell phone diffuses light better and hides minor defects.
Is it possible to make a canopy without welding?
Yes, a metal canopy can be assembled using bolted joints. For this purpose, special connecting elements (“crabs”) and shaped parts are used. This requires more precise preparation of the holes, but allows you to assemble the structure yourself without a welding machine. Wooden canopies are also assembled without welding, using dowels and bolts.