A well-designed drainage complex will reliably protect the facade and foundation from the destructive effect of rain and melt streams. If you correctly draw up a project and follow all technological rules, it is possible to mount a water drainage system from the roof in a low-rise building with your own hands, without hiring a professional team.
Purpose and scope of drainage system
The gutter complex consists of gutters and pipe parts, through which water from the roof is collected in a single stream and discharged from the building.
In the absence of a drainage system, sedimentary and melt water floods the foundation and walls, building materials are quickly destroyed. Wet walls retain heat worse and look ugly.
A well-designed roof drain helps to avoid this. Modern designs and materials make it possible to create efficient gutters that are in harmony with the design of the building and the surrounding landscape.
Types and arrangement of drainage systems from the roof
According to the method of manufacture, gutters are divided into home-made and created at specialized enterprises. The first ones are distinguished by low cost price and original design. You can make drainage systems from various materials at hand, even from plastic bottles. The disadvantage is the complexity of joining the nodes. In addition, artisan gutters tend to be less durable than industrial gutters. The latter are made in accordance with GOSTs, manufacturers give a guarantee for the products. Their price is higher, especially considering the professional installation.
The best option is the creation of an individual scheme of the drainage complex, the purchase of finished parts and self-assembly.
The principle of operation of drainage systems also differs. They can work in three ways:
- Unorganized. Water flows naturally flow down from the roof under the influence of gravity.
- Organized internal. The entire network of drainage elements is located inside the building.
- Organized outdoor. The complex is installed on the outside of the house.
In the first case, in order to somehow protect the walls and the foundation, the roof outlets are made large (not less than 0.6 m), and streams of rain or melted snow flow down them to the ground. According to SNiP 31-06-2009, a similar scheme is implemented in houses with no more than 5 floors, with a pitched roof. It should be tilted towards the yard area. It is allowed to erect houses with similar roofs only in areas where the level of precipitation is minimal (no more than 30 cm per year).
The optimal way of drainage from pitched roofs is external. The effluent is directed to the storm sewer in an organized manner. The complex is easy to install and does not require serious investments. In this case, the configuration of the roof must be taken into account:
- The roof drainage system with one slope consists of one pipe and is mounted in the lower part with a slope.
- Drainage systems on gable structures require a separate drain for each side of the roof.
- If the roof is hipped, the gutter and pipe parts are mounted along the perimeter of the building.
- For a gable roof, the drain is installed in separate sections in the inter-gable space.
The internal version is more often equipped on flat roofs with a soft coating. If the roof structure has slopes, it is used very rarely, exclusively in industrial facilities.Slate roofs are not adapted to this type of drainage; only the outer version is suitable for them.
On flat roofs, external parapet drains can be used. For this, special parapet funnels are installed.
Manufacturing material
A budget option is drainage systems made of polymeric materials. The pluses include:
- resistance to fading in the sun;
- resistance to corrosion;
- strength;
- light weight;
- wide temperature range (from 40 degrees of frost to 70 degrees of heat);
- ease of installation;
- variety of colors and configurations of system elements.
The disadvantages of PVC parts are a high coefficient of linear expansion and low impact resistance. The last drawback after a correct installation is not so important. However, it is not recommended to install polymer systems on high-rise buildings.
Prices for plastic drainage systems from the roof are democratic - from 1900 rubles for a minimum set.
The complexes are mounted using the glue method or using rubber seals. The first method is better because it uses "cold welding" and the parts are joined at the molecular level. The second option requires periodic replacement of the seals.
More durable gutters made of metal: copper or steel alloys. The latter are galvanized or coated with a polymer layer. Metallic drains are installed on buildings of any height.
Copper products are more resistant to corrosion, they are flexible, durable, not afraid of heavy loads and aggressive environments. However, the cost of each part is not less than 1000 rubles.
Galvanized or polymer-coated complexes are cheaper - from 5000 rubles for a minimum set. But if used improperly, there is a risk of moisture penetration under the coating and the formation of rust, which will shorten the service life.
Advantages and disadvantages of metal gutters:
pros | Minuses |
Impact resistance | Heavy weight |
Reliability | Small selection of shades |
Resistance to heavy loads, which is important in regions with heavy rainfall | A small number of elements, which makes it impossible to install on complex roofs |
Fire resistance | Complexity of installation work |
No linear expansion | Rusting of steel parts with poor quality coating |
Most brands produce gutter systems from various materials. For example, in the company "Unicma" you can buy all types of drainage systems: from non-ferrous metals, plastic, steel with galvanized or polymer coating.
Design and calculations
When creating a home-made complex or before installing an external roof drainage system from finished parts, you will need to create a project with a drawing. An accurate calculation is required of how many and what parts will be needed, taking into account all the technical characteristics. You will need:
- sewage pipes;
- drainage gutters;
- funnels for connecting the first two elements;
- caps for the ends of the grooved parts;
- fastening brackets and clamps to fix structural elements;
- filter grids.
Design work begins with measuring the roof perimeter. The length of the gutter parts must be at least five percent greater than the perimeter of the building so that a drop can be created for the smooth transportation of sediments. The slope is 0.5–2 cm per meter. When measuring the perimeter, consider overhangs and prominent architectural details such as chimneys.
Drainage funnels are placed between the gutter sections, followed by installation of pipe drains to them. The distance between them should not exceed 24 m, but it is advisable to install them every 10 m. The optimum diameter of the funnels and pipes is 8–12 m, so as not to increase the slope.
The dimensions of the elements of the wastewater complex may differ slightly from different suppliers, so it is advisable to purchase all the parts in one place.
If a steel or copper gutter is installed, the brackets are fixed every 100 cm, if from polymers - every 50 cm.In addition, a storm drainage scheme is created to drain the drains.
The edge of the gutter is located at least 3 cm below the plane of the roof, otherwise there is a risk of damage to the element by sliding snow.
Installation of the structure
Before installing the catchment complex, collect the necessary tools:
- electric screwdriver;
- hacksaw or grinder;
- scissors for metal or a cutter for plastic;
- tape measure, building level.
You will need a portable ladder of the required height and fastening hardware, depending on the material of the walls of the building.
The device of the drainage complex is carried out from top to bottom. First, the drainage gutters are fixed, after which the drainage pipes are mounted. To make it easier to work, mark out where exactly the brackets will be installed.
A step-by-step guide will help you make a water drain from the roof from finished parts with your own hands:
- Install the funnel at the bottom of the markings and the bracket at the top by attaching them to the rafters or wind board. Pull the string between the funnel and the bracket, fasten the remaining holders along it. The distance from the outermost ones to the funnel or coupling is no more than 100 mm. The distance between the rest of the holders is about 60 cm.
- Clip the groove pieces onto the holders. The joining of the two parts is carried out using a coupling.
- Secure the corner pieces that connect the gutter lines at the outside and inside corners of the building. Install plugs on the ends.
- Attach an elbow to the drain funnel, which is connected with a piece of pipe to a similar part, but looking in the opposite direction. This will make it possible to bring the drainpipe to the wall of the house to the maximum. Secure the second knee with a clamp.
- Fasten the drain pipe clamps to the walls at a distance of no more than 170 cm from each other.
- Install a drain piece at a distance of 30 cm from the ground surface. Assemble all parts strictly vertically.
When all the weirs are installed, install the intermediate clamps and tighten the fixing elements.
A properly assembled drainage complex will last several decades without any complaints.