Products for building
The New "Włochaty" Roof Screen stands out by combining high strength with very high vapour permeability. This combination is exceptional in the membrane market, as in previous production technologies, increases in strength and surface weight resulted in decreased vapour permeability.
The new three-layer screen has a high surface weight of 265 g/m² and is entirely made of polypropylene (PP). The bottom layer is a needled non-woven fabric, which serves as both an anti-condensation and levelling layer.
The "Włochaty" Roof Screen is highly versatile, but its needled layer makes it particularly suitable for use under coverings installed on decking and sheathing. It is recommended for all types of metal sheets joined with standing seams or laid with overlaps (karo-type tile systems).
The new screen has a thickness of approximately 1.5 mm in its free state and about 0.9 mm when compressed. This thickness allows it to compensate for minor unevenness, such as protruding nail heads and other small deviations in the sheathing.
It performs equally well under all tile-type coverings like slates, fibre-cement panels, or metal (aluminium) tiles. Its versatility also lies in the fact that, thanks to its thick active layer (a film weighing 80 g/m²), it can be installed as an underlayment on all types of roofs, including those classified as flat, provided the manufacturer of the primary roofing allows for such materials in their system.
It is thick and strong enough to meet the requirements of any structure and covering. It performs just as excellently under coverings laid on battens (e.g., roof tiles, profiled metal sheets, etc.), regardless of whether they are installed on sheathing or directly on the structure and thermal insulation.
| PARAMETER | VALUE |
| Material | polypropylene - 3 layers |
| Mass [g/m²] | 265 ±20 |
| Sd – equivalent air layer thickness [m] | 0.015 (+0.06/-0.01) |
| Tensile strength [N/5cm] | lengthwise: 500 (±200) crosswise: 450 (±200) |
| Elongation at break [%] | lengthwise: 70 (±40) crosswise: 100 (±40) |
| Nail tear resistance [N] | lengthwise: 400 (±150) crosswise: 500 (±150) |
| Water tightness class | W1 |
| Fire resistance class | E |
| Roll dimensions [m] | width 1.6 m × length 25 m |
| UV resistance* | 26 weeks |
| Period without main covering** | 4 weeks |
* According to laboratory studies conducted under artificial aging, this period is based on average annual UV exposure from sunlight in Central Europe.
** The period for which the membrane remains on the roof without the primary covering should be as short as possible; the more sunny days there are, the shorter this period should be.
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