Roof of roofing felt by own hands

When performing the roof of outbuildings and garages as a roof covering, inexpensive, but very popular material - roofing material is often used. Most often it is used to cover the roof with a small angle of inclination, that is where other types of coatings can not provide good waterproofing. The roof of the roofing felt by its own hands is completely feasible, it is necessary only to understand the technology of laying and the features of materials.

Roof covering with roofing felt always has several layers, the lower layers are made of a lining felt that does not have a protective layer, and the last top layer is made of roofing material with sprinkling. Sprinkling of ruberoid has a different size of the fraction, the stability of the roofing material depends on the size of the particles.

Ruberoid stamps: how to deal with them?

First of all, it is necessary to understand what this material is. The traditional, long-known ruberoid is a roll of dense cardboard, which has bitumen impregnation, with a denser top layer, smooth or having a sprinkling. More modern modifications of ruberoid can be made on the basis of fiberglass, which provides additional strength and waterproofness of the material. The so-called euroruberoid has, in addition, a floating polymer layer, which when heated forms a viscous surface, which ensures the gluing of the ruberoid to the substrate. Euroruberoid does not require the application of mastic between layers.

Traditional roofing felt has an alphanumeric marking, indicating its purpose and technical characteristics. For each layer of coating, it is necessary to choose the appropriate ruberoid.

The first letter in the marking is always "P", it means the type of material - roofing material. The second can be "K" - roofing, or "P" - lining. The third letter in the marking indicates the appearance of the upper layer: "K" or "M" - coarse or fine-grained, "H" - scaly, "P" - pulverulent. It can also be marked "E" - elastic. The figures in the labeling mean the density of the cardboard in grams per square meter. For roofing layers, a roofing felt of the grade RPP or RPE is chosen, for the upper layer - RKK, RCM, RKhC, RCP.The welded ruberoid is marked with RM and RO accordingly.

Determination of the number of layers and material calculation

The number of layers of roofing material to create a reliable coating depends on the roof slope and the possible snow load, as well as on the reliability of the roof itself and its ability to withstand the weight of roofing material and bitumen. The smaller the slope of the roof, the more layers of roofing material required to perform a sealed waterproof coating.

Flat roofs with a slope angle of up to 2-3 degrees usually require the laying of at least four layers of roofing material: three layers of grade РПП-350, the fourth - of mark РКМ-350.If the roof is used to move people, the underlying layers should be four - this roof is capable of withstanding the weight of a person and any snow load.

Roofs with an angle of inclination from 3 to 6 degrees are usually covered with three layers of roofing material - two underlaying and one roofing. If the roof slope is from 6 to 15 degrees, two layers of roofing material are sufficient. On roofs with an angle of inclination of more than 15 degrees the roofing material is rarely used, usually as a waterproofing layer for other types of coating: corrugated board, ondulin or slate.

When calculating the material, it is necessary to take into account not only the number of layers, but also the obligatory overlap of 10 cm for each strip, as well as a stock of 20 cm by the length of the stripes at the ridge and at the roof slope. The resulting amount of material is rounded up to the area of ​​the roll.

Mastics for gluing roofing material

To ensure a firm fit of roofing material to the roof, it is glued to bituminous mastic. An exception is a fused roofing material, which already has an adhesive layer. Bituminous mastic can be as cold, ready, and hot, which must be preheated at a temperature of 150-200 degrees.

Cold mastic based on solvents is usually sold in cans, stir thoroughly before use. Cold mastic is much easier to use, but it dries longer, in addition, it does not provide sufficient strength of the coating. Therefore, when covering the roof with a ruberoid, hot mastic is more often used.

Preparation of hot mastic takes some time. Bitumen is sold in pieces in a solid form, and it must be heated to a viscous state, after which reinforcing filler is added to it. Heat the bitumen in the cauldron, bucket, barrel or any other container with a blowtorch or open flame until foam and rare bubbles form. The foam is removed, and the filler is added to the bitumen in an amount of 20% of the volume. Filler can serve as a sawdust, peat, sand, fiber. Mastic thoroughly mixed and hot on the surface of the roof.

Technology for laying roofing material

1. Surfaces of the roof are free from residues of old coating, debris, dirt and dust. The concrete surface can be treated with a primer for bitumen mastic, which improves adhesion. The wooden roof is sewed with a continuous crate of edging boards, all the cracks and holes are punctured.
2. Cut roofing material into strips of necessary length with a margin of 20 cm at both ends. Strips ruberoid on the roof with a slope of up to 3 degrees can be placed both along the slope, and across. With a greater slope, to avoid stagnation of water at the joints, the strips are laid along the slope.
3. The first layer of bitumen mastic is applied to the prepared surface and immediately, without waiting for it to solidify, lay pre-cut strips of ruberoid of PPP or RPE type with an overlap of 10 cm and carefully roll them with a roller to achieve complete adherence of the material to the surface. The roller can be made from a piece of metal pipe, or from a soft, but heavy material rolled into a roll.
   

   Laying of layers of bituminous mastic

4. Apply a second layer of mastic and lay the next layer of ruberoid with a displacement of ½ of the strip, so that the middle of the strip is on the knock of the previous layer. So lay all the backing layers.
5. Before laying the last layer of roofing paper, check the roof for the absence of bubbles and air pockets, if necessary, roll them again. The last layer of ruberoid grade RKK or RKM is laid in a similar way, gluing it on the bituminous mastic, while ensuring that the joints are glued qualitatively, there is no damage to the surface of the material and sprinkling.
   

   Bituminous mastic sheets are rolled with a special roller

Technology of laying a fused roofing material

1. The preparation of the roof surface is practically the same as preparing for a plywood roofing material. Some manufacturers produce roll welded materials that can be laid on top of the old coating, which significantly reduces the time to prepare the surface.
2. At the first coating of the roof, the surface must be treated with a polymer or bitumen mastic for better adhesion of the material and improvement of waterproofing properties.
3. A roll of welded ruberoid is slightly rolled in place and heated with a blowtorch until it is whitened and the adhesive layer begins to dissolve, then firmly press it against the surface and roll it with a roller. Continuing to roll the roll by 20-30 cm, repeat the procedure. The overlap of layers of roofing material should also be about 10 cm.
   

   Rolling out the layers of weldable roofing material

4. With qualitative preparation of the surface, one or two layers of welded roofing material usually suffice, depending on the roof slope. At the same time, for the lower layer, the Euroruberoid of the RM mark is chosen, for the lower layer - the grade RK with the sprinkle.

Properly laid roofing material has a warranty service life of 5 years, but with good care and timely cleaning of the roof from snow and debris, repair of damaged areas such a roof can last more than 25 years. A roof made of ruberoid, made by own hands, will help considerably save money for the construction of a garage and other structures.