The roof structure contains many elements - these are both load-bearing and directly protective. Its main function is to protect the attic and the house itself from various negative environmental influences. However, for this function to be performed properly, additional elements (additional parts that increase the life of the roof) are important, including a drip for the roof, which will save the pediment and cornice from natural precipitation.
If you disassemble the design of the drip, then you can come to the conclusion that the device is the so-called overhang apron. It is a flat metal strip fixed to the cornice, which protects the facade and basement from water.
Its principle of operation can be described as follows:
- formed due to rain or snow that melted under the influence of heat, the liquid begins to flow down the roof and passes to the drip;
- passing along the apron, the liquid is redirected into the gutter and from there it is discharged outside through the drain pipe.
In summer, this system prevents the development of mold on the surface of the walls and in the space under the roof. And also it does not allow the masonry mortar to wash out, and the cornice to rot due to excessive moisture. In winter, the heating of the drip prevents ice from spreading into the space under the roof, additionally protects and strengthens the edge of the roof from strong gusts of wind and icicles. If we refuse to install the apron, then subsequently condensate will accumulate in the under-roof space, which will fall on the frontal board and rafters. As a result, all wooden elements will become completely unusable. And it is also important for the chimney steam room to remove the resulting condensation.
In addition, the dropper also performs an aesthetic function, decorating the appearance of the roof. Thanks to him, it becomes possible to build both simple bends and complex, multi-level ebb systems with drainage channels and storage tanks. The installation of the apron is not limited exclusively to one roof, it is also successfully installed over window and door openings.
If we consider the finished roof, then a kind of multi-level structure should be obtained, consisting of such elements as:
- counter-battens - a part that is responsible for ventilation and is a roofing system consisting of wooden bars. They are installed above the rafters, on top of the hydro-barrier;
- lathing - a frame that fits on the rafters at a right angle;
- waterproofing films (water-repellent layer) or roofing material;
- apron strips;
- drain hook;
- external eaves strip.
Quite often, the cornice bar and the drip are confused with each other and generalize them as elements for removing moisture. This confusion results in only one element being installed. In no case should they be confused, since both are extremely important to keep the roof dry.
Therefore, it is important to remember that the main differences between these parts are as follows:
- the drip is used to remove drops that accumulate on the waterproofing layer, and is attached under it;
- the eaves plank is installed under a layer of covering material and helps in removing liquid from the outside of the roof.
Types and purpose
In appearance, the dropper is a curved strip made of metal. Quite often it is compared to a ridge strip for corrugated board, only of a different configuration. Skates are additional elements that provide air exchange in the area under the surface. An additional element is cast from galvanized steel, and a protective polymer coating is applied on top, which can be of very different colors. It is thanks to this that it is not difficult to choose an apron in color for any roof.
Based on the purpose of the strip and the place of its attachment, there are two types of apron.
- Eaves drip. It is installed on the eaves of the building. In the corner form, there are two folds: the first is located in the middle between the skirt and the apron itself, thereby separating them; the second is necessary to increase the level of the ability to resist deformation under the influence of external influences. The correct roof structure includes gutters, before the installation of which the cornice must be hung with special fastening hooks, at the same moment the slats are installed. It is worth considering that it is better to fasten the aprons as if with an overlap, they overlap each other by about 2-3 cm, and knowing their size, you can calculate in advance how many elements are needed for the entire cornice. All this work is carried out until the roof is laid, for example, a profiled sheet.
- Pediment dripper. It is used if the work is carried out with a waterproof carpet. Such a double drip protects the gable overhang from the destructive influence of natural factors. It is attached over the lining carpet and after that it already closes with the cornice strip, then moves towards the ridge. However, if the finishing is made with a hard coating, then other materials are used, for example, end trims.
The apron is based on galvanized steel with a polymer coating (PVC). The material "stainless steel" is characterized by increased strength, immunity to humidity and sudden temperature fluctuations. Aprons are made from thin aluminum sheets using special bending machines. The coating is a polymer material that is sometimes specially designed for soft bituminous shingles and is characterized by resistance to corrosion changes. The thickness of one sheet usually does not exceed 0.5 mm. Polyester can be matte (PEMA) or glossy (PE).
Glossy polyester has lower performance and therefore costs less. The surface is smooth, and shines when exposed to sunlight. Usually, a special protective polyethylene film is applied to the front side (where the paint is) to protect the material from light mechanical damage during transportation and at the time of cutting. Matte polyester is similar to glossy, but its technical performance is higher, which means it will cost more. On the front surface there are irregularities imperceptible to the human eye, due to which the sun's rays are reflected in a different way and the sheet does not shine.
Before buying planks around the entire perimeter of the house, you need to count their number, so it is important to know their length. Typically, the length of the drip is no more than 1-2 meters, however, there are one and a half meter models (150 cm). The price of a product directly depends on its length, width and what kind of coating is used. In order to calculate in advance the approximate cost of the work, it is necessary to measure the length of all the sides to be processed on which the aprons will be attached. One running meter will cost about 100-250 rubles. Therefore, you need to multiply the resulting length by the cost of one running meter and you will get an approximate amount spent.
However, do not forget about consumables: self-tapping screws, rivets, silicone sealant, mastic and others. It is also important to take into account that if the work is carried out independently, then the possibility of hiring professional workers is not excluded, and this can cost up to 500 rubles per running meter. You cannot buy them in building stores, since they are produced only by individual order in a construction company. This takes into account the parameters of the house and roofing.
Assembly and installation
The planks are installed at the stage of completing the construction of the roof, but, as indicated earlier, before the roof is laid. At the time of the work, the structure of the product used must be taken into account. If there is a need to shorten the bar, then it is preferable to do this manually with scissors or an electric jigsaw. If you do this with a grinder, then the upper polymer layer will simply burn out due to the high speed of rotation of the cutting disc, which will adversely affect the dropper and in the future it will rust.
To work, you will need the following tools:
- scissors for metal;
- galvanized roofing nails;
- for self-tapping screws with a press washer measuring 1.2–2 cm, you will need a screwdriver.
Installation of a cornice drip includes several steps.
- The gutter hooks must be installed first. An important point of this stage is that it is required to increase the level of strength of the cornice part of the sheathing so that under the load from the weight of ice or water it does not undergo deformation along with the roof. Further, one at a time, it is necessary to lay the eaves strips, they should lie a little in tension and not dangle.
- It is necessary to fix the initial plank with self-tapping screws with an indent of 20 cm. Then the next plank is overlapped and also needs to be fixed. To prevent the ingress of liquid to the wooden covering from the purlins, at the time of fixation, rubber seals can be placed under the caps of the screws. If at the time of work the rigid edges interfere with the joining of the elements, then they are simply cut off with special scissors for metal.
- To prevent damage to the surface of the apron during transportation, there is a special film coating. Before starting installation, this film must be removed. Upon completion of fastening, each element should be carefully inspected to check for a tight fit. Quite often, masters put sheet rubber under the drip, which provides complete waterproofing. Only after installing all the strips can you proceed to laying the profile.
The step-by-step installation of a pediment drip includes several simple steps. If a waterproofing carpet is chosen, for example, bituminous shingles, then after fixing the eaves plank, you can start installing the gable aprons.
- The starting point in the installation should be the cornice, since it is necessary to preserve the natural flow of the removed water. For installation, the left or right end of the strip is joined to the edge of the very last cornice drip. It is necessary to overlap the ends with an overlap of 2 cm, and fix it with a nail in the contact area, then continue diagonally every other time, calculating one nail per 10 cm.To ensure complete tightness, the surface can be treated with mastic.
- Further steps are identical to the first element, but the distance between the nails is not 10, but 15 cm. And also, if necessary, you need to cut the stiffeners and remove the manufacturer's protective film.
- When working with a soft roof, it is important to consider the correct location of the planks. They need to be fixed over the lining, and cornice tiles should be glued above them. At the end of the work, a shingle roof or metal tile is laid on top of the pediment relative to the first row with glued tile overlaps.
- Do not forget that the gable drip serves rather as a guiding element that prevents water from entering the gable and sends it down.
Materials made on the basis of bitumen are characterized by the following distinctive features:
- waterproofing and good water repellency;
- roofing does not require knowledge of any special techniques and takes a short period of time;
- soft roof withstands exposure to ultraviolet rays and sudden temperature changes;
- provides sound insulation;
- low cost of the material.
You can meet a waterproof carpet in several main types.
- Shingles look like a rectangular module with curly cutouts along one edge. The basis of the tile is pressed glass cloth, which is subsequently impregnated with a bituminous solution. The front part of the sheet is covered with a sprinkling of copper or balsat, which ensures high-quality preservation of the material from adverse influences. The inner part is represented by a layer of polymer with a protective film. The modules can be used for any type of roofing.
- The rolled version contains fiberglass with the addition of synthetic materials, which are then impregnated. The downside is the lack of steam and heat insulation.
- The membrane can be rubber or polymer. To ensure reliable tightness and increase strength, the existing gaps are filled with hot air.
To make a crate, you need to take materials such as:
- board, not less than three centimeters thick;
- plywood sheets;
- oriented strand boards.
When filling the lathing, the step depends on what material was chosen for the roof. Most often, solid fixation is found, but since wood is characterized by natural expansion, it is better to leave a gap of at least 5 cm. Oriented strand boards are attached with self-tapping screws or brushed nails, leaving a gap of 3 mm. If plywood is chosen as a facing material, then it must be moisture-resistant and grooved. The optimum sheet thickness ranges from 10 to 20 cm. Each wooden element must be thoroughly dried before work, and then treated with a special antiseptic solution.
Tips from the pros
It is worth paying attention to some of the nuances and tips highlighted by professionals.
- In order for the water to be removed in the correct direction, the pediment drip must be installed starting from the lower edge of the roof and the slope. Plumb lines from the cornice and gable apron should fit together. To do this, they are fastened, observing a checkerboard order and a two-centimeter overlap, using carnations. After that, bituminous waterproofing mastic is applied to the joining line using a spatula.
- Do not forget to remove the protective film from the plumb line. Mounting of the roof is carried out using nails, observing an indent of 15 cm. In order for the elements to dock better, it is recommended to cut the stiffening ribs, planks are inserted closely into these cuts.
- When processing a waterproof carpet, it must be covered with ridge-cornice tiles. After that, the strips are already laid, which cover the fragments and places of the joining line of most of the tiles.
- Compliance with the order of hammering in nails - every other diagonal. Where the roof is adjacent, wooden slats 5x5 cm are used. Lining material is laid on top, fastened with bitumen and nails. The next layer is a metal bar that is nailed down. Finally, the joint areas and various crevices are treated with a sealing compound. A correct gutter structure must channel sediment into the gutter.
- It is important that the installation of the drip does not disturb the adequate and advising circulation of air masses in the space under the roof. If you miss this moment, there is a high risk of an unpleasant situation when the accumulation of excess moisture that has not come out begins, which will ruin the insulation and adversely affect all wooden elements. To prevent the formation of ice on the surface of the riding boards, the apron should be installed as close to the gutter as possible.
- When choosing a drip, you should pay attention to what material it is made of. The metal must be of high quality, durable and resistant to the effects of corrosive changes. Once a year, you should inspect the entire water drainage system and from time to time clean the plumb line with funnels from various debris. This is done in preventive measures to prevent the formation of blockages and blockages of drains.
In fact, attaching the drip bar to roofs is not difficult.
However, do not forget that some types of work should have already been completed by this time, namely:
- installation of the frontal board;
- filing of roof overhangs;
- installation of drainage fasteners;
- assembly of the lathing.
For information on how to mount the drip yourself, see the next video.