It should be noted that in Moscow, at a number of experimental arguments for roofs with a zero bias, a five -layer was accepted – a carpet well proven in operation. In this regard, for residential buildings up to 14 w wide, with combined coatings with a zero bias, you can recommend the use of a five -layer roller carpet.
In Yerevan, cold bitumen mastics are used as a roofing layer, prepared from a mixture of bitumen pasta and mineral filler, which uses cement. To protect the layer of mastic from destruction, it is painted with a composition of LEBT, which is a mobile mass of cream -shaped consistency, consisting of ethylene varnish (31%), bitumen (4%) and pigmenting and plasticizing tuff powder (65%). This composition is applied with a brush in the same way painting with oil paint. When examining combined coatings with a roof of mastic painted with the composition of the LEBT, in some cases there was an insufficient durability of the film.
To increase the mechanical strength and a thin layer of Bitumen mastic or isol mastic, preheated to 180-200 ° C, into which pure dry sand or small gravel is applied to the upper layer of the carpet from isol.
The base (screed) serves to ensure a flat and strong surface under the roofing carpet, as well as reducing the influence of deformation efforts on it caused by a change in the temperature of the outer air. It is usually made of a layer of cement mortar of the brand 75-100. In order for the screed to perceive stretching efforts that occur with changes in the temperature of the outdoor air, it is recommended (especially in areas with continental and climate) to reinforce a wire from a wire with a diameter of 2 mm with a cell size of 200 x 200 mm.
