Installation of a drain funnel on a flat roof. Why do we need a roof funnel, varieties, rules for installing a gutter system. Choosing a drainage system
This article will tell you how and why you need to install drain funnels for a flat roof. After reading, you will learn what funnels are, what they consist of, and you will also understand the basic principles of their installation. This information will help determine the structural features of the building under construction at the design stage.
Why do we need drain funnels on a flat roof
Water does not linger on the slopes of the roofs. However, if the building has a flat roof, during rain and snowfall, heavy masses of precipitation will accumulate on it. They can lead to the destruction of waterproofing, the accumulation of dirt and even to the collapse of the roof. In addition, wind and rainwater can bring plant seeds to the roof. Germinating, they will further increase the load on the roofing surface.
Drain funnel for a flat roof - types, design features and materials of manufacture
The water inlet funnel for a flat roof is made of the following materials:
Plastic PVC funnels.
Metal coated with zinc. This is the most common funnel material. It is inexpensive and does its job well.
Copper. This material is not popular due to the high cost of products.
Funnels are:
flat. Such funnels are installed on flat roofs that they plan to use frequently. If the roof is covered with asphalt or tiles, flat funnels are mounted on a level with them.
Bell-type. They have a protective filter mesh. This mesh protects the drain from clogging. Its shape is a cap rising above the level of the roof.
Funnels can be either horizontal or vertical. The difference between them lies in the location of the drain hole relative to the facade of the building. Funnels with a horizontal outlet have a discharge pipe that passes through the insulation layer. Such funnels are not very convenient, because when performing technical work to replace drainage pipes or funnels, it is required to open a significant section of the roof. If you lay a horizontal line above the freezing line, then ice jams can form in the pipes. Ice plugs in pipes are fraught with leaks and stagnant water. The horizontal system is used on roofs that do not have an attic. On regular flat roofs ah use funnels with a vertical outlet.
A heating cable can be connected to the funnel. Due to this, the snow around will melt.
You can find funnels of combined designs.
The structure of the catchment funnel
A typical funnel consists of:
pressure ring, which fits snugly to the roof and provides tightness;
gratings preventing objects from entering the drainage system;
horizontal or vertical branch pipe;
water intake, which transmits water flows into pipes;
oil seals reinforcing the places where the pipe is connected to the pipe;
fixing flanges;
lids over the product.
Drain funnel for a flat roof - types and methods of installation
Installation is divided by type of installation:
Outdoor structures, which are mounted around the perimeter of the house.
Internal, which are laid during construction inside the walls and pass into the sewer. The tightness of such systems cannot be neglected. The result of poor quality work will be the rapid course of corrosion processes.
In the case of a flat roof, the installation of an internal drain funnel is the most preferred solution. Horizontal pipes are laid under waterproofing and insulation.
Drainage systems can be:
gravity, that is, with a slope: water flows down under the influence of gravity;
vacuum without bias: work on the principle drain tank, for which they received the second name - "siphon".
Flat roof drain funnels: installation and heating
Funnels are installed so as to ensure the convergence of water into the sinks under the influence of gravity. They should be located in the lowest areas of the roof. To ensure the flow of water, a roof slope of 2% is sufficient. If there is no such slope, then it is created artificially - for the entire roof or the so-called "decline" is made - with the help of expanded clay, insulation slabs or concrete.
The roof surface is divided into equal areas of regular geometric shapes. The lower part of the product is mounted in the base of the roof to connect the funnel to the downpipe. After the waterproofing and insulation are laid, the lower and upper parts of the funnel are connected using an O-ring. Between the layers of roofing material there should be a plastic funnel apron. Secure it with an additional bitumen apron. From above, all these layers are covered with mastic or bitumen again. A protective grill is installed.
They check the quality of the work done by throwing a bucket of water at a distance of 2 meters from the funnel.
Calculation of drain funnels on a flat roof
At least 2 funnels should be installed on the roof of the house to provide the necessary protection in case of unforeseen situations such as severe weather or blockages in pipes. One funnel should be for every 150 or 200 square meters roofs. Funnels are installed at a distance of 25 meters from each other if the length of the house itself exceeds 25 meters. The minimum distance from the funnel to the funnel is 50 centimeters. Do not install the funnel closer than 1 meter to the edge of the roof.
If the building is divided into sections, each of them must be equipped with its own storm sewer funnel on the roof.
On our website you can find the most . In the filters, you can set the desired direction, the presence of gas, water, electricity and other communications.
Principles for the selection and installation of a roof drain funnel
When installing flat roof drains, there are a few simple rules to keep in mind. Without their observance, the efficiency of drainage structures will drop sharply:
On a roof made of a metal profile or a fold, they are installed metal funnels.
For bitumen roofing or polymer coatings, choose polymer funnels.
The connection of the funnel with the roof must be completely sealed. To do this, you can stick an additional waterproofing layer, extending it directly on the sides of the funnel. If there are several layers of waterproofing on the roof, the funnel is installed between them.
The funnel must have removable cover and protection against dirt so that the latter does not fall into the drain. In addition, the protection system will help to avoid clogging with leaves, branches, sand and other types of street debris.
Need conduct heating to the funnels so that the water in them does not freeze.
Flat roof drain: the specifics of the construction of the internal and external version
Drainage can be built outside and inside the building. Each of these methods has its own characteristics. For example, the internal design does not affect appearance buildings, and the external one is easier to install and repair.
Internal drain
In order to properly lay the internal drainage system, it must be designed in advance. The pipeline path should be as short as possible, and the junction with storm sewers should be convenient and reliable.
Risers can be located near living rooms. In this case, it is not necessary to install heating on the section of the pipe that passes through the rooms. Wiring is done through strobes, boxes or mines. It will be necessary to insulate the drain passing through the attic.
If the building is not heated, it will be necessary to solve the problem of heating the pipes in order to avoid freezing of the water that will flow into them. This is usually done with a heating cable. It is necessary to provide the riser with a cleaning revision at a height of one meter from the ground.
On our website you can find contacts of construction companies that offer services roof design and repair. You can directly communicate with representatives by visiting the exhibition of houses "Low-Rise Country".
Pipes located inside the building are not subject to such sudden temperature changes as systems built outside. Also, the appearance of the building is not overloaded with additional frills in the form of an outdoor drainage system. This gives the house neatness and simplifies the decoration of the exterior. However, to clean internal system much more difficult.
From the funnels to the risers, water leaves through special outlet pipes. Branch lines are laid underground or a suspended network is built right in the house. In order for water to pass through horizontally laid pipes in a suspended network, they are installed with a slope of 5 millimeters per linear meter. If a grid system cannot be installed, lateral lines can be run underground and connected to a storm sewer. It costs more, and later repairs will be less convenient.
External drainage
The external drain is suitable for the southern regions, where there is little rainfall - no more than 300 millimeters per year. open system the drainage system is easier to clean and repair if it has been damaged by bad weather.
The construction of an external drain has many specific features. To avoid damage and corrosion external walls buildings with flat roof y, you need to build barriers. The coverings of these sides must be metal or concrete.
Special holes are made in the sides to bring out the drainage gutters. A galvanized apron must be applied to the joints of the coating of the sides. So water will not penetrate into the gaps between the joints.
Drainage gutters extend outside the house and roof. In contrast, for internal drainage, funnels are placed on the roof itself, at a distance from the edges.
Video description
Funnels of the internal drain of flat roofs:
Drainage systems, which is located outside, can be:
unorganized. This option is suitable for dry areas. Water is drained through the overhangs on the cornices.
Organized. In this case, the sediments are collected in an outer funnel with guide rims. Also, water can drain into a gutter, from which liquid is drained into storm sewer or straight into the ground.
In some cases, filtering equipment is installed in the drainage system, which makes it possible to obtain from it process water, which can be used, for example, to operate toilets.
Video description
In the video you can see a drain funnel for a flat roof:
Conclusion
Understanding the abundant range of drains and technical details can be difficult at first. To make the right decision, determine your priorities and goals for the drainage system and funnels. The choice will narrow down significantly when it becomes clear what specific results you want to achieve at the end of the work. If during the winter a lot of snow falls on the roof, it is clear that it will be necessary to install a heating system to prevent icing. If the gutters extending beyond the walls do not fit into the design of the building, it is clear that it would be preferable to hide the drain.
For the calculation and installation of the drainage system by the most the best option will contact the experts. Building codes contain a lot of nuances that in any case will need to be taken into account for safety purposes. Professionals will help you calculate an estimate based on your needs, and perform all work quickly and with a guarantee.
You can buy funnels for the drainage system with diameters from 100 mm from us. up to 220 mm. at competitive prices directly from a reliable manufacturer without intermediary margins.
Gutter funnel made of galvanized steel- This the best choice in terms of low price and high quality. Standard diameters of funnels for drains are produced in accordance with GOST 7623-84. We maintain a warehouse stock, many items are in stock.
We will quickly deliver in Moscow and the Moscow region.
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Current base price list. Want cheaper- send us an application and your details to [email protected] We will prepare a special price offer for you!
Funnels made of galvanized steel |
Unit rev. | Price |
| Drain funnel galvanized 100 mm. | PCS. | 188.27 rubles |
| Drain funnel galvanized 120 mm. | PCS. | $201.80 |
| Drain funnel galvanized 130 mm. | PCS. | $223.95 |
| Drain funnel galvanized 140 mm. | PCS. | $228.87 |
| Drain funnel galvanized 150 mm. | PCS. | $242.41 |
| Drain funnel galvanized 160 mm. | PCS. | $255.94 |
| Drain funnel galvanized 180 mm. | PCS. | $270.71 |
| Drain funnel galvanized 200 mm. | PCS. | $311.32 |
| Drain funnel galvanized 220 mm. | PCS. | $338.39 |
The cost of products with painting
Funnels powder-coated in RAL colors |
Unit rev. | Price |
| Funnel drain diameter 100 mm. painted galvanized | PCS. | on request |
| Funnel drain diameter 120 mm. painted galvanized | PCS. | on request |
| Funnel drain diameter 130 mm. painted galvanized | PCS. | on request |
| Funnel drain diameter 140 mm. painted galvanized | PCS. | on request |
| Funnel drain diameter 150 mm. painted galvanized | PCS. | on request |
| Funnel drain diameter 160 mm. painted galvanized | PCS. | on request |
| Funnel drain diameter 180 mm. painted galvanized | PCS. | on request |
| Funnel drain diameter 200 mm. painted galvanized | PCS. | on request |
| Funnel drain diameter 220 mm. painted galvanized | PCS. | on request |
Prices for other galvanized outdoor gutter components that we manufacture are published on our website vodostoki.ru in the Drainage prices section
Why is it profitable to buy a funnel for a drain from us?
We, as manufacturers, can make the most interesting offers for the price. Standard diameters are available from stock. In production, we use special equipment that allows us to produce reliable and high-quality products.
Excess rain, melt water on the roof surface, or its accumulation due to improperly equipped drainage, adversely affects the stability of any building, as well as its operational period. If from pitched roof structures with a certain slope water flows down natural way, then flat roofs require competent arrangement of the drainage system. A similar issue is provided by the ability to solve drain funnels for a flat roof. In this case, it is important to choose the right products, to determine their sufficient quantity.
In this article
Gutter options
For the production of TechnoNIKOL drain funnels installed on a flat roof, copper, galvanized steel, polyvinyl chloride can be used. Copper products are less popular, as they are not suitable for all types of roofing and are quite expensive. The most commonly used inexpensive funnels made of galvanized steel. Polyvinyl chloride specimens are perfect for soft tiling, ondulin, shinglas.
There are the following designs of drainage roof funnels:
- flat. Element drainage system mounted at the level of the roof surface, used for operated roofs, on which asphalt or tile material is used as a coating.
- Bell-type. These products got this name because of the special protective mesh used for them (foliage catcher), made in the form of a cap and rising above the roofing surface. This version of the drain funnel, in addition to fulfilling its main task, additionally protects the system from clogging with various debris.
- heated. The funnel for a flat roof is equipped with a heat cable, thanks to which winter period it is heated, accordingly, the formation of ice is prevented, and melt water freely flows down the drainage system.
- With horizontal, vertical outlet.
All of the listed types of TechnoNIKOL drain funnels can be purchased on the construction market in specialized stores.
Drainage funnel device
On the modern construction market, a wide variety of options for drain fittings are presented, differing in design, material of manufacture, quality, and, accordingly, price.
A standard drainage system consists of the following components:
- frame from galvanized steel, plastic or cast iron;
- lattice- filter element (foliage catcher) preventing contamination of the system;
- intake pipe- connects the fitting and the downpipe;
- gaskets, sealing rings- sealing elements at the junction of the funnel with the roof surface;
- thermal cable - additional element design, preventing the formation of ice in the system, respectively, providing an effective discharge of melt water in the winter season.
Important! The drainage system of the roof, including drain funnels, must be cleaned periodically so that an unexpected downpour does not lead to a violation of the roof structure.
Tips for installing roof drains on a flat roof
When arranging a water intake system on a flat roof, it is recommended to consider the following points:
- The roofing surface is previously recommended to be conditionally divided into identical sections. For effective drainage of water from the roof, one drain funnel for a flat roof is calculated for a plot whose area should not exceed 200 m 2, and the diameter of the downpipe should not be less than 10 cm.
- When placing the receiving components of the water intake system for maximum effective removal water, the slope of the roof surface to them should be at least 2 percent.
- When fixing the water intake funnel, it is recommended to provide a little free space for the possibility of moving the receiver relative to the intake pipe.
- Receivers, regardless of the area of the roof, there must be at least two or one water intake device and a separate storm drain.
- If the waterproofing material is laid in two layers, then the water receiver is mounted between them. If one layer of waterproofing is used, then an additional piece of insulation made of a similar material is applied, the area of \u200b\u200bwhich must be at least one square.
- For flange connection it is recommended to use heated bitumen;
- For better fixation on the roof of the water intakes, you can additionally use specialized mechanical connections.
Precipitation has a positive effect on vegetation, contributes to the saturation of the earth with moisture, useful properties and are needed to fill rivers and reservoirs. But, in addition to useful moments, precipitation has an inactive effect on buildings. Constant exposure can ruin concrete, wood and other Decoration Materials. Therefore, it must be purposefully removed from the roof. For this purpose, a special drainage system is used. Roof drain funnels play an important role in it. It is they who catch the streams of water and direct them through the pipe system.
What are the features of such funnels? How do they differ from each other? How to properly install them? We will learn the answers to these questions from this article.
Types of gutters for the roof
Depending on the design of the roof, there are different types drainage system. The roofs themselves can be divided into two large groups:
- Flat roofs.
- Inclined roofs, with different levels of slope.
The drainage system is also divided into two varieties, starting from the roof group:
If we talk about funnels in one and the other system, then in the first case it plays a crucial role. Her choice should be treated with special attention. Gutter funnel in the photo:
It is these funnels for flat roofs that will be discussed, since horizontal drains have built-in funnels that do not need to be selected. It's about about gravitational-vacuum systems. Such a vertical type drain was invented more than 30 years ago. His homeland is Scandinavia. Now it is widespread not only in Europe, but also in other countries. The principle of operation is simple, it is based on the so-called ejection ability of the liquid in the pipes. In this case, one medium entrains another, in the water drainage system it is air. In the riser, gaseous masses begin to move upward. But when it enters the system waste water, it goes down under the influence of gravity, and the air layer goes in the opposite direction. It turns out a vacuum environment in which moisture begins to flow at high speed into the collector through a pipe system. The movement of water is determined by pressure from air masses, therefore, for its free movement of the slope is not required.
Such a system has many advantages:
- High flow rate.
- Can be used to create narrow pipes.
- The structure will self-clean.
- The drain is light weight.
- For installation, you do not need to engage in a large amount of earthwork.
The note! If we compare such vacuum system and a traditional horizontal drain, the difference is immediately visible.
For example, gravity-vacuum-type funnels, in which the branch pipe has a cross section of 75 mm, can pass through about 15 liters of precipitation in just 1 s. But the traditional type system is much inferior, since in order to pass 1 s of 15 liters of water, you need a funnel with a diameter of 200 mm.
Funnel materials
Internal gutter funnels are made of different materials which have their own characteristics, advantages and disadvantages. Before you buy a funnel, you need to find out this information. Here are the materials from which the elements of the system are made:
After evaluating all the features of each type of funnel, you can choose one or another option.
Requirements for products for the drainage system
Installation of the system is specified in GOST 25336-82. The main points are related to the throughput of funnels, as well as their number on a horizontal roof. The roof area for one drain funnel is prescribed in SNIP 2.04.01-85, in the section "Internal drains". So it says there that there should be at least two funnels on the roof and in one valley. The greatest distance between them should be 48 m no more. It turns out that 1 funnel is required for 230 m 2. At the same time, its diameter should be 10 cm, not less.
Given these indicators, you need to purchase one or more funnels for the house, and then install them. The roof area for one drain funnel is 230 m 2, so you won’t have to spend a lot of money. In addition, it is worth paying attention to the fact that the funnel can become clogged with debris. This is foliage, and dust, and cellophane. So that they do not penetrate the system and do not clog it, a special grate is installed on the drain funnel on the roof. It performs a protective function, while not affecting the throughput in any way. However, so that the leaves accumulated on the grate do not prevent water from entering the funnel, you will have to look at the drain from time to time.
Varieties of funnels for a flat roof
There are several parameters by which storm water inlets for a flat roof are distinguished. Today, companies produce a variety of models, which allows you to easily choose a product for yourself. So the types are:
Important! Funnels for precipitation have different sections. Be that as it may, the diameter of the funnel and the drain pipe must match. A 10 cm section is usually used. This will be enough to redirect all the water from the roof to storm system.
Installation of a funnel on the roof
Before installing a drainage funnel and other elements of the system, the following nuances should be taken into account:
Now you can start the installation process. It is slightly different from each other, depending on the roofing and type of funnels. However, the principle is the same for all. We will consider installation on soft roof. The instruction is as follows: - To begin with, a niche should be cut around the technological hole. Most houses already have it.
- Next, you need to take the funnel and plant it directly on the concrete. If there is no fold on it, then glue is used.
- Next you need to apply a buty primer.
- After that, along the carved niche, and then along the entire perimeter, you need to lay a soft roof.
- The structure continues to grow. The kit comes with a fixing ring that needs to be installed in its place and screwed. A hole is cut in the center.
- It remains only to install the cap or filter grill for the funnel.
You can see more about installation in this video:
As for the installation of a funnel for a vacuum drain, the installation process can be seen here:
Summing up
A funnel for a gutter system is an integral part of any gutter system. Thanks to it, it is possible to qualitatively and quickly divert storm or melt water from the surface of the roof, flat or sloping. Otherwise, the presence of water will adversely affect all structural elements. It remains only to choose one or another version of the funnel for a flat roof and start installing it. If you have any questions, you can ask them in the comments below the article. Experienced professionals will answer them for you.
Sergey Novozhilov - expert in roofing materials with 9 years of experience practical work in area engineering solutions in construction.
One of the most destructive factors that shorten the life of a roof is water. However, no matter what the design of the roof, there are fairly reliable methods that can effectively withstand precipitation and melt water. In this article, we will talk about what drain funnels are for a flat roof, and how to properly install them.
It is worth noting that the slopes of the roofs make it easy to cope with the problem of intense precipitation, since water simply flows off them. But in those cases when the roof is absolutely flat, puddles form on it, since the moisture does not have time to evaporate. As a result, the waterproofing is subject to gradual destruction, and a layer of dirt accumulates on the roof surface.
Often, wind-blown plant seeds germinate in this layer, which further destroy the roofing cake. It is the removal of melt and rainwater into the storm sewer system that is the main purpose of drain funnels on flat roofs.
What is a drainage system
The term "drainage system" implies a set of devices through which the collection, transportation and removal of melt and rainwater from the surface of a flat roof takes place.
There are such types of drains:
- Disorganized, or, natural. In this case, it means that precipitation rolls down steep slopes. For roofs with large slopes, this method is quite acceptable, but it is absolutely not suitable for flat roofs.
- External. It includes a set of pipes and gutters for the outflow of water, mounted on rafter legs or wind boards. In such drains, precipitation falls by gravity and is discharged out into the storm sewer. For flat roofs, this type of construction is applicable only in buildings of a small area.
- Interior. This type of drain is laid in the thickness roofing cake. It is most preferred for flat roofs.
Gutters internal type for flat roofs
The structure of the internal drainage system offers the placement of its elements under the insulation and waterproofing layer.
Such a system contains the following components:
- roof funnel- they collect and filter water;
- horizontal pipes - laid under insulation and waterproofing with a slope - for a gravity drain, and without a slope - for a vacuum one;
- vertical sewers - they transport sediments from horizontal pipes into the storm.
Depending on the principle of fluid movement, vacuum and gravity drainage systems are distinguished. With a vacuum type of drain, the liquid quickly fills the pipe throughout its entire thickness, forming a continuous water column. As it moves down, the air mass tends to rise up, creating a vacuum. The resulting space, as it were, sucks water from the drain funnel, ensures its quick removal from the roof surface and prevents the accumulation of debris due to fast movement liquids.
The structure of the catchment funnel
By design, a catchment funnel for a flat roof consists of the following elements:
- the lower section, which is laid in the base of the roofing cake;
- sealing gasket sealing the joint between the upper and lower sections of the funnel;
- the upper section that passes through the layer of waterproofing and insulation;
- grate - serves to prevent large debris from entering the downpipe.
Please note that reliable sealing of the joint between the upper and lower sections of the funnel of the drainage system is mandatory for the effective operation of the roof. As a rule, it is the ingress of water into the seams of the funnel that causes leaks.
Varieties of roof funnels
On sale you can find funnels for flat roofs made of polyvinyl chloride, copper or galvanized steel. The latter are the most commonly used because they differ affordable price. Copper products are too expensive for buyers, so they are not in high demand. In addition, they can not be combined with any roofing. Polyvinyl chloride roof funnels are used on roofs made of ondulin, shinglas and soft tiles.
According to the structure, the following types of products are distinguished:
- Flat. Such products are mounted flush with the roof surface, covered with asphalt or tiles.
- Kolpakova. This funnel is necessarily equipped with a protective grill that prevents debris and dirt from entering the pipe. The product rises above the surface, resembling a glass or cap.
- With horizontal or vertical type of release.
- With heating elements. A heating cable is mounted inside such a funnel, which melts the snow and prevents the water from freezing and clogging the drain.
Principles for installing a roof drain funnel
Professional craftsmen have developed some standards for correct installation funnel on a soft roof:
- Installation of the device must be carried out in such places, the level of which is lower than the main surface of the roof. Minimum slope between the funnel and the main roof can be 2º, and in a segment of 50 cm it should increase to 5º. The necessary slope is created by plates of insulating material, concrete screed or expanded clay backfill.
- The number of funnels on the surface of a flat roof is determined on the basis of one unit for every 25 m of length.
- Whatever the area of the roof, it must have at least two drain funnels. They will allow you to quickly withdraw a large number of water from the roof if one of the gutters fails.
- The minimum distance between devices is 50 cm, and there must be at least 1 meter to the visor.
Installation sequence on a soft, flat roof
Installation of funnels for removing precipitation from a flat roof is carried out as follows:
- First, the roof is marked out, divided into equal geometric figures. In the central part of each of them with the help of expanded clay, a layer of insulation and concrete screed, organize a deepening. The lower part of the funnel joins with a downpipe laid horizontally and is mounted at the base of the roofing pie.
- Upon completion of waterproofing and insulation work, a sealing ring is laid, and the two parts of the funnel are connected.
- The upper part of the device is placed between two layers of roofing material, after which it is fixed with a built-up bitumen apron.
- At the end, a layer of bitumen or mastic is applied, and a protective mesh is also mounted.
- To make sure that the water intake funnel is installed correctly and tightly, a bucket of water is poured onto the roof two meters from it and they check how quickly all the liquid will move into the drain.
It is worth noting that the drainage system, in particular roof funnels, needs periodic diagnostics and cleaning. This will significantly extend the life of your roof, as well as provide you with rainwater to water your garden plants.