Decra 700 High Performance Breather Membrane
|
Advantages
|
- Outstanding breathability characteristics.
- UV stabilised.
- Maintains its performance at virtually all temperatures.
- Large roll size, reduces wastage, increases speed and efficiency of installers.
- Entirely recyclable.
- Energy efficient.
- Extremely durable.
- Lightweight and strong.
|
Decra Roof Systems in partnership with it’s sister companies within the Icopal group, the world’s largest producer of roofing felts, is now able to offer from stock high performance breather membrane ideally suited for use with the Decra Roof System.
Product Information:
Decra 700 High Performance Breather membrane is manufactured from a specially formulated microporous film laminated between two layers of non-woven polypropylene providing one of the highest permeability figures of any breather membrane.
Technical Data:
|
Recommended horizontal laps for underlay
|
| Pitch |
Minimum headlap |
Minimum
sidelap |
|
|
Not fully
supported |
Fully
supported |
| 10° to 12° |
300mm |
200mm |
100 - 150mm |
| 12.5° to 14° |
225mm |
150mm |
100 - 150mm |
| 15° to 34° |
150mm |
100mm |
100 - 150mm |
| 35° + |
100mm |
75mm |
100 - 150mm |
NOTE 1. Any penetrations to the underlay should be suitably sealed to prevent water ingress.
NOTE 2. Roofing underlay laps to valleys should comply with recommendation’s of BS 5534; Part 1:1997 section 4.2.1.6
|
Performance & Properties
|
Water Vapour Transmission:
|
1196g/m²- 17 |
|
(BS 3177, 25°c/75% RH)
|
|
|
Water Vapour Resistance:
|
0.17MNs/g |
(BS 3177, 25°c/75% RH)
|
|
|
Hydrostatic Head of Water:
|
7.31m |
|
(BS EN 20811)
|
|
|
Water Resistance:
|
Pass |
|
(BBA t1/15)
|
|
|
|
|
|
Nail Tear Resistance:
|
85N (longitudinally) |
|
(N per 50mm)
|
|
|
|
|
|
Tensile Strength:
|
230N (longitudinally) |
|
(N per 50mm)
|
160N (transversally) |
|
|
|
|
Coefficient of Friction:
|
0.85 dry |
|
|
0.73 wet |
|
|
|
Size and Coverage
|
|
Roll Length:
|
50m |
|
Roll Width: |
1.5m |
|
Thickness:
|
0.6mm |
|
Weight:
|
0.14kg/m² |
|
Colour:
|
Blue top surface/Anthracite underside |
|
Cover per roll:
|
70m² (approx. at 100mm lap)*
67.5m² (approx. at 150mm lap)*
63.75m² (approx. at 225mm lap)*
60m² (approx. at 300mm lap)*
*no allowance made in the above coverage’s for side laps and any wastage.
|
Installation
Decra 700 High Performance Breather Membrane must be installed with the blue side uppermost.
For ease and accuracy of installation, overlap guidelines of 150mm from both edges are printed throughout the roll.
As per all types of breather membrane, at eaves the breather membrane should terminate in line with the front edge of the fascia board and to comply with the recommendations of DTLR Robust Detailing, BRE Defects Action Sheet No9 and BRE Good Repair Guides an appropriate Decra Eaves Guard must be installed underneath the breather membrane.