NBS Source
I'm a manufacturer

Compare variants

Permavent Apex Air/ Vapour Permeable Roofing Underlay - Air Open Vapour Open Membrane
Permavent Apex Air/ Vapour Permeable Roofing Underlay - Air Open Vapour Open Membrane
Permavent Apex Air/ Vapour Permeable Roofing Underlay - Air Open Vapour Open Membrane

Verified 3 months ago

Permavent Ltd

Taped 50

Verified 3 months ago

Permavent Ltd

Untaped 50

Verified 3 months ago

Permavent Ltd

Untaped 75

Summary
Three-layer air and vapour open membrane for use as a pitched roof underlay.
Three-layer air and vapour open membrane for use as a pitched roof underlay.
Three-layer air and vapour open membrane for use as a pitched roof underlay.
Application

Pitched (10–70°) roof underlay.

Fully compliant with BS 5534: 2014 + A2 2018 and an integrated tape version can be installed in all UK wind zones.

Pitched (10–70°) roof underlay.

Fully compliant with BS 5534: 2014 + A2 2018 and an integrated tape version can be installed in all UK wind zones.

Pitched (10–70°) roof underlay.

Fully compliant with BS 5534: 2014 + A2 2018 and an integrated tape version can be installed in all UK wind zones.

Description

A three‑layer breather membrane for pitched‑roof underlay, Permavent APEX combines vapour and air permeability with outstanding water‑resistance and condensation control. It forms a reliable secondary barrier against water ingress and removes the need for dedicated low‑ or high‑level ventilation in most standard roof builds.

Available in three formats

  • Taped 50 – 1 m × 50 m roll with integrated double‑sided tape
  • Untaped 50 – 1 m × 50 m roll, ready for use with site‑chosen tapes or sealants
  • Untaped 75 – 1.5 m × 50 m roll for wider coverage when desired

All three meet the same rigorous performance standards and are fully compliant with BS 5534:2014 + A2 2018, suitable for installation across every UK wind zone.

Key Features & Benefits

  • BBA‑certified for cold non‑ventilated, cold ventilated and warm non‑ventilated pitched roofs (up to 70° pitch)
  • Air & vapour permeable (180 g/m²) to help manage moisture vapour inside the roof build
  • Highly water resistant (W1 rating to EN 13589), keeping out wind‑driven rain
  • UV‑stable for up to three months, allowing flexibility on site
  • Taped version
    • Built‑in double tape speeds up laps and seals, reducing overall membrane usage by up to 25%
    • Ideal where labour or tape compatibility is a concern
  • Untaped versions
    • Maximum flexibility to pair with your preferred tape or adhesive detailers
    • 75 cm width variant (Untaped 75) covers more area per run, cutting down installation time on wider spans

Whether you choose the convenience of integrated tape or the adaptability of untaped rolls (in either 1 m or 1.5 m widths), Permavent APEX delivers the same high‑performance breather membrane you can trust.

A three‑layer breather membrane for pitched‑roof underlay, Permavent APEX combines vapour and air permeability with outstanding water‑resistance and condensation control. It forms a reliable secondary barrier against water ingress and removes the need for dedicated low‑ or high‑level ventilation in most standard roof builds.

Available in three formats

  • Taped 50 – 1 m × 50 m roll with integrated double‑sided tape
  • Untaped 50 – 1 m × 50 m roll, ready for use with site‑chosen tapes or sealants
  • Untaped 75 – 1.5 m × 50 m roll for wider coverage when desired

All three meet the same rigorous performance standards and are fully compliant with BS 5534:2014 + A2 2018, suitable for installation across every UK wind zone.

Key Features & Benefits

  • BBA‑certified for cold non‑ventilated, cold ventilated and warm non‑ventilated pitched roofs (up to 70° pitch)
  • Air & vapour permeable (180 g/m²) to help manage moisture vapour inside the roof build
  • Highly water resistant (W1 rating to EN 13589), keeping out wind‑driven rain
  • UV‑stable for up to three months, allowing flexibility on site
  • Taped version
    • Built‑in double tape speeds up laps and seals, reducing overall membrane usage by up to 25%
    • Ideal where labour or tape compatibility is a concern
  • Untaped versions
    • Maximum flexibility to pair with your preferred tape or adhesive detailers
    • 75 cm width variant (Untaped 75) covers more area per run, cutting down installation time on wider spans

Whether you choose the convenience of integrated tape or the adaptability of untaped rolls (in either 1 m or 1.5 m widths), Permavent APEX delivers the same high‑performance breather membrane you can trust.

A three‑layer breather membrane for pitched‑roof underlay, Permavent APEX combines vapour and air permeability with outstanding water‑resistance and condensation control. It forms a reliable secondary barrier against water ingress and removes the need for dedicated low‑ or high‑level ventilation in most standard roof builds.

Available in three formats

  • Taped 50 – 1 m × 50 m roll with integrated double‑sided tape
  • Untaped 50 – 1 m × 50 m roll, ready for use with site‑chosen tapes or sealants
  • Untaped 75 – 1.5 m × 50 m roll for wider coverage when desired

All three meet the same rigorous performance standards and are fully compliant with BS 5534:2014 + A2 2018, suitable for installation across every UK wind zone.

Key Features & Benefits

  • BBA‑certified for cold non‑ventilated, cold ventilated and warm non‑ventilated pitched roofs (up to 70° pitch)
  • Air & vapour permeable (180 g/m²) to help manage moisture vapour inside the roof build
  • Highly water resistant (W1 rating to EN 13589), keeping out wind‑driven rain
  • UV‑stable for up to three months, allowing flexibility on site
  • Taped version
    • Built‑in double tape speeds up laps and seals, reducing overall membrane usage by up to 25%
    • Ideal where labour or tape compatibility is a concern
  • Untaped versions
    • Maximum flexibility to pair with your preferred tape or adhesive detailers
    • 75 cm width variant (Untaped 75) covers more area per run, cutting down installation time on wider spans

Whether you choose the convenience of integrated tape or the adaptability of untaped rolls (in either 1 m or 1.5 m widths), Permavent APEX delivers the same high‑performance breather membrane you can trust.

Color
Blue
Blue
Blue
Material
Polypropylene
Polypropylene
Polypropylene
Shape
Rectangle
Rectangle
Rectangle
Length
50000 mm
50000 mm
50000 mm
Width
1000 mm, 1500 mm
1000 mm, 1500 mm
1000 mm, 1500 mm
Warranty description
15 year
15 year
15 year
SKU Code
APEXB50
APEXB50UNTAPED
APEXB75UNTAPED
GTIN/EAN
5060747290121
5060747290138
5060747291036

Specification

Classification data
Standard
To BS EN 13859-1 and BS 5534:2014 + A2 2018.
To BS EN 13859-1 and BS 5534:2014 + A2 2018.
To BS EN 13859-1 and BS 5534:2014 + A2 2018.
Class (minimum)
W1.
W1.
W1.
Third-party certification
British Board of Agrément (BBA) certificate 23/6867, Product Sheets 1 and 2.
British Board of Agrément (BBA) certificate 23/6867, Product Sheets 1 and 2.
British Board of Agrément (BBA) certificate 23/6867, Product Sheets 1 and 2.
Performance criteria
-
-
-
Water vapour properties
To EN 12572, Sd: 0.01 m.
To EN 12572, Sd: 0.01 m.
To EN 12572, Sd: 0.01 m.
Fire performance
Reaction to fire: To EN 13501-1: Class E.
Reaction to fire: To EN 13501-1: Class E.
Reaction to fire: To EN 13501-1: Class E.
Tensile properties
To BS EN 12311-1 (MD/CD), 330/ 270 N/50mm.
To BS EN 12311-1 (MD/CD), 330/ 270 N/50mm.
To BS EN 12311-1 (MD/CD), 330/ 270 N/50mm.
Material
Polypropylene non-woven.
Polypropylene non-woven.
Polypropylene non-woven.
Form
Three-layer composite with integral double-sided self-adhesive tape.
Three-layer composite.
Three-layer composite.
Weight (minimum)
180 g/m².
180 g/m².
180 g/m².
Thickness (minimum)
Manufacturer's standard.
Manufacturer's standard.
Manufacturer's standard.

Additional properties

Roll size
1 x 50 m.
1 x 50 m.
1.5 x 50 m.
Adhesive
Double sided, air and water-tight, three-dimensionally formable acrylic adhesive.
-
-
Air permeability
To EN 12114, >20 m³/m²·h at 50 pa.
To EN 12114, >20 m³/m²·h at 50 pa.
To EN 12114, >20 m³/m²·h at 50 pa.
Tear resistance
To EN 12310-1 (MD/ CD), 210/ 210 N/50mm.
To EN 12310-1 (MD/ CD), 210/ 210 N/50mm.
To EN 12310-1 (MD/ CD), 210/ 210 N/50mm.
CoverageArea
50 m².
50 m².
75 m².
Flexibility at low temperature
To EN 13859-1, -40°C.
To EN 13859-1, -40°C.
To EN 13859-1, -40°C.

Sustainability data

Contains Red List materials
No
No
No
Country of material origin
United Kingdom
United Kingdom
United Kingdom
Country of product manufacture
United Kingdom
United Kingdom
United Kingdom
Material
Polypropylene
Polypropylene
Polypropylene
Recyclability
100% Recyclable.
100% Recyclable.
100% Recyclable.
Recycled content
100 %
100 %
100 %
Expected Life
Lifetime
Lifetime
Lifetime