Installation of a lining carpet under a soft tile.

In accordance with the norms of SP 17.13330.2017 (SNiP II-26-76 Roofs), the structure of the roofing pie for flexible tiles assumes the presence of a lining carpet between the rafter system and the tiled roof. This intermediate position predetermines the functions of the lining carpet:
Additional waterproofing of wooden elements of the roof structure and insulation;
Sealing complex sections of the roof - ridges, cornices, junctions;
Reinforcement of the base in the area of expansion joints of solid flooring;
Smoothing out irregularities, differences in the height of the flooring in order to level the surface for the finishing tile coating;
Creation of an additional soundproof "pillow".
Rule number 1. Neglecting underlayment will not only shorten the life of the roof, but will also automatically void the manufacturer's warranty on shingles.
Of key importance is the properties of the bituminous composition, on which the waterproofing qualities of the lining carpet depend:
Ordinary oxidized bitumen loses its plasticity already at +10°C.
SBS-modified bitumen retains its elasticity at lower temperatures and even returns to its original shape after slight deformation.
The structure of the underlayment can include bituminous coating on only one side of the base, such as Döcke PIE COMFORT, or on both sides, as in other Döcke PIE underlayment models.
The fastening method predetermines not only the strength characteristics of the substrate, but also the waterproofing qualities of the seams.
In accordance with the method of fastening, 3 types of materials are distinguished:
Self-adhesive, their working side is completely covered with adhesive bitumen (Döcke PIE FIX PLAST and FIX GLASS). They provide perfect fixation and reliable insulation, therefore they are used to finish the most important structural elements of the roof - eaves and gable overhangs, valley gutters and areas adjacent to pipes, walls, etc.
Glueless, designed for mechanical fixation (Döcke PIE STANDARD, COMFORT and COMFORT GLASS). For fastening, galvanized nails are used, which must necessarily be covered with the next canvas, and the width of the overlap must be at least 10-15 cm.
Combined, the structure of which is supplemented from above with a mounting adhesive strip (Döcke PIE STANDARD PLUS and FIX PLAST).