Installing drains: how to properly install a drain and attach it to the roof
One of the key stages of arrangement of the roofing system at home is drainage. Without its organization it is impossible to protect the facade of the building from rain and water flows during the period of snow melting.
How is the installation of drains and what to consider when installing a structure, we consider in the article.
Highlights in the design of gutters
The question of how the drainage system will be equipped should be decided at the design stage of the building.
In the preparation of calculations, you need to be guided by the requirements of the current SNiP 2.04.01-85. Such an approach will allow, taking into account all the nuances, to correctly select the optimal variant of the design.
The main points that should be followed when designing a drainage system:
- Having made a copy of the roof drawing, draw a plan for the location of the elements of the drain.
- Calculate the total area of the roof and all its slopes separately, taking into account the adjacent vertical walls.
- Taking the indications of the intensity of rain in a given area as a basis, determine the capacity of the system.
- In accordance with the obtained values, determine the diameter of the installed drainpipes, the number and cross-section of the drain funnels, as well as the frequency of their placement along the wall of the building.
The result should be a system capable of collecting and draining the maximum amount of fluid.
At the design stage it is important to determine the location of the risers so that they do not violate the exterior composition. Most often they are placed in the corners of the building, but it is perfectly acceptable to arrange the arrangement in the niche created by the bay window.
If the discharge coming from the drain pipe will be carried out on the blind area,It is better to remove the risers as far as possible from the entrances to the basements, the basement ventilation vents and the footpaths laid near the house.
The components of the drainage system
The system includes two groups of parts - horizontal and vertical drainage parts. Together they have about a dozen types of structural elements, each of which performs its task.
Structural elements of the drainage system are:
- Drainpipes - key functional elements of the system, designed to move the mass of water from the roof;
- gutters - narrow channels for collecting and redirecting water;
- funnels - conical sockets in the upper part of the pipe are designed to collect, delay and drain water flowing down the gutters;
- knees - designs in the form of short curved pipe segments are installed to change the direction of water flow;
- brackets - fasteners for fixing the gutter to the roof;
- seals - additional elements ensure the strength of fastening at the joints;
- clamps - fasteners for fixing the structure to the facade of the building.
When constructing the drainage system on long-sloped roofs, guides are additionally installed. Their main purpose is to reduce the flow rate of water along the surface of the roof.
The form of gutters and brackets can be any. There are products with a round and semicircular cross section, U-shaped and trapezoidal shape.
Differ in the gutter and the method of connection with the bracket. The easiest way to install systems that involve fixing is through a simple snap. The swivel latches included in the package make it possible to dismantle a part of the chute without any special troubles if it is necessary to replace or carry out repair work.
Water collecting funnels made of polymers come in three versions: through passage, left and right.
The connection of drainpipes and the laying of water outlets from the basement of a building cannot be done without engaging the knees. Their number is determined on the basis that three elbows are required to be installed on each drainpipe: one at the bottom and two at the top.
For fixing the gutter construction to the facade of the building used clamps. For metal plumbing choose fasteners with screw-down elements and a long pin. For PVC structures - plastic clamps with two points of support.
Choices of material types
The price of the drainage system depends on several factors, one of which is the material of manufacture. Variants of materials that you can choose when arranging the drainage system, the modern market offers a lot. The choice depends on the appearance of the building and the aesthetic views of its owner.
The most widespread products made of polymers and metal. Each species has its advantages and disadvantages:
- Plastic - lightweight, durable and at the same time quite easy to handle material. At a low price, it shows excellent operating parameters. Installation of PVC gutters does not cause any particular difficulties.
- Galvanized steel is a stronger and more durable material than a polymer. To give the product a more presentable look, manufacturers coat steel with a polymer coating.
- Aluminum is a lightweight and easy-to-use material, whose service life reaches more than half a century.
- Copper is a beautiful, durable, but quite expensive metal. But he is vulnerable to the damaging effects of electrolytic vapor. To minimize the risk, all elements of the system should be made of the same material.
Polyvinyl chloride, used for the production of components, is much lighter than metal. This makes it possible to install brackets with a smaller cross-section, while not losing the mechanical strength of the structure. But when installing PVC structures should be taken into account and linear variations in size.
The compensating couplings enable the main elements of the system to be shortened and lengthened without the risk of deformation. They are also used in the installation of metal gutters, despite the fact that they have much less thermal expansion.
The material for the manufacture of seals is EPDM rubber. It is a modern analogue of rubber.
To further protect the rubber and simplify the installation process, the seals are additionally treated with silicone grease.
Drainpipes produce lengths from one to four meters. They come in rectangular and circular sections. On their performance is not displayed. The choice is limited only by the constructive decision of the drainage system and the design decision of the front part of the house.
When purchasing drainpipes made of polymeric materials, keep in mind that they have the same diameter over their entire length. Therefore, to connect them to each other, special couplings will need to be used, which entails additional costs.
Calculation of the required number of elements
This rather important event is better to be entrusted to specialists who sell drainage systems, or to the masters of the company who provide installation roofing services. In the absence of such a possibility, the calculation can be performed on its own.
The main points of a competent calculation:
- Gutter. The total length of the canals should correspond to the length of all roof slopes used to collect water. Their joining is carried out using connectors.
- Water intake funnels. They are installed in the outer corners of the building and additionally placed every 8-12 meters so that the total slope of the channels is not too large.
- Drainpipes. The number of products corresponds to the number of craters, and the length - the distance from the roof to the surface of the earth.
- Brackets. The number of brackets is determined on the basis that one element is required for each meter of the channel. Additional holders will be required for the funnels in the center and the wall and in the corner of the house.
The number of clamps depends on the height of the building. But in any case, each individual installed section of the pipe is fixed with at least one clamp. When installing a drainpipe in a one-story building, it is often enough to have three fasteners located at the top, bottom and in the middle of the product.
When calculating, they take as a basis the condition that per 1 sq. M of the roof in the horizontal projection should be 1.5 sq. Cm of the sectional area of the drain and funnel. For example: the cross-sectional area of a pipe D 100 mm is 78.5 sq. Cm. This is an average value. Depending on whether it is necessary to install the system in regions with high rainfall, or, conversely, in arid areas, the calculations are amended.
Bracket attachment methods
Installing brackets according to the rules is still at the stage preceding the laying of the roof. If the fixing is done after the cover is laid, then ordinary short hooks are used as fasteners.
Depending on the shape of the bracket, the elements can be fixed in one of three ways:
- Fixing to the frontal board of the roof - it is used when you need to install the system on the finished roof.
- Fastening on the rafter leg - used at the stage of installation, prior to the laying of the roofing material.
- Fixing on the lower edge of the flooring or the first lath of the batten is used for the roof, the step between the rafters of which exceeds the mark of 600 mm.
The arms intended for fixing to a frontal roofing board, most often are included in the package of the systems executed from polyvinylchloride.
Metal brackets for attachment to the frontal roofing board make shorter. If the design of the roof does not provide a frontal board, use the combined brackets.They are equipped with extensions made of steel. Due to this, it is convenient to attach them directly to the rafter foot.
In case it is impossible to provide access to the rafters, metal crutches are attached to the wall. ” They act as a support for further mounting of the metal gutter.
The method of fixation, involving fastening on the rafter foot, is effective in arranging the roofs of houses in regions with heavy rainfall. Apply it and, if necessary, drainage of water from the roofs that have a large area, for the shelter of which heavy-weight coatings are used.
In this method, hooks are slid over the base and set at an equidistant distance in order to provide the desired slope of the chute.
The third method of fixation, which involves mounting on the crate, is most often used in the construction of a roof with a coating of ondulin or metal tile. It is chosen only if the recesses cannot reduce the carrying capacity of the batten in the area of the eaves.
Choosing the third method, fixing it is important to remember that only strict adherence to the rules of installation and the order of installation can ensure the reliability and durability of the structure.
Technology of installation of drains
Installation of equipment for gutters is carried out after the completion of facing works. There is nothing difficult in how to prepare and install a drain. Installation of PVC systems can even be performed by a beginner.
Mounting of horizontal elements
A set of tools that will be needed during the work:
- marking cord;
- roulette length of at least 3 meters;
- universal screwdriver;
- a hammer;
- flat bending;
- pipe tongs.
Some craftsmen cutting metal gutters and pipes are performed using a grinder. But this is far from the best solution, since the rotating disk heats up the polymer coating during operation. And this may cause damage to the elements of the drain during operation.
Installation of brackets start with the installation of the extreme elements. Then the distance between the drain pipes is divided into equal intervals of length 60-80 cm for the installation of the remaining hooks.
In order to simplify the task for yourself, having ensured an even slope of the gutters in the direction of the water receiving funnels, it is better to pull the cord when marking. The boundary values of the slope - from 2 to 5 mm per linear meter. To improve the accuracy of installation, it is better to designate several key lines, pulling the cord in two or three rows for this.
In the process of mounting brackets, the slope is achieved by shifting short fasteners vertically or by bending the metal holders in the calculated position. In order not to disturb the galvanization and not to damage the polymer coating, a special tool, a flat bending, is used to bend the fasteners.
Gathering drainage system can be done in one of two ways:
- All elements are laid out on the ground in a horizontal position and then inserted into the brackets fixed along the building perimeter. This method is applicable for small houses and small areas of decoration.
- The traditional option involves the phased assembly of all elements of the system directly on the building.
Installation of the drain should be made in the order “from top to bottom”: first install water intakes, then connect the drain risers. This is dictated by the technological features of the drainage system.
Before attaching the gutters to parts of the roof, they first mount the funnels, not forgetting to take into account possible temperature expansions.Then install the gutters, placing them 2 cm below the line, which conditionally stands as a continuation of the overhang. They are produced in lengths of 3-4 meters. Chutes, which occupy extreme positions in the line, will most likely have to be cut.
When installing the gutters, it should be remembered that they should be at least one-third blocked by the overhang of the eaves. Ideally, the overlap should be half of its own diameter.
A swivel element, connector or plug closes the line of grooves. When joining elements on the inner surface put a layer of glue with a thickness of 5 mm.
An important point: the gutters made of polyvinyl chloride, can not be joined at close range. This can cause cracking and damage the structure.
Arrangement of drain and drain pipes
To move from the funnel to the drain, involve two knees and one straight stretch. For roofs with narrow eaves, the transition is collected by connecting only the upper and lower elbows.The distance of the lower knee to the wall of the building is usually determined by the manufacturer.
Installation of drains should not cause any special difficulties. Four-meter segments are easily joined to each other with clutches. Connect the details, moving from top to bottom. The drain is attached to the lower end of the pipe with glue.
If the site is equipped with a stormwater system, the task is simplified - the drainpipe is simply brought into the collecting well, or placed 5-10 cm from the surface of the tray.
For the possibility of fixing the drain riser mark the point of placement of clamps. The lowest point should be located directly above the drain. The riser clamps tighten not too tightly so that the pipe at the time of linear expansion could slightly move up or down.
Conclusions and useful video on the topic
The advice of professional installers will always come in handy if you want to install a roof drain system yourself.
Example of assembling and mounting elements:
Design and install a drain using a modern modular system under the power of any owner. The main thing is to have minimal building skills and not be afraid of heights.