Case Study

A Grade II listed building undergoing significant renovation, supported by Cadw Conservation, Bat Conservation, DEP Architects and Bridgend Council

Westfield House

A Grade II listed building renovation

Permavent APEX and Easy Roof System provide a solution for a Grade II listed building renovation.

View products used in project


Bridgend, South Wales

May 2020


Ensuring the successful and compliant roofing renovation to a Grade II listed building.

Main roof – 360m2. Low pitch elevations – 60m2.

Why Permavent was chosen

Permavent were asked to provide technical support for the replacement of all roof areas, requiring collaboration with the appointed architect and roofing contractor. Additional discussions with bat ecologists were also undertaken, to ensure the safety and preservation of any nesting.

To bring the property in-line with current British Standards, Permavent APEX was introduced to all main roof areas. The unique air & vapour permeability of this roofing underlay ensured the main roof design required no additional roofing ventilation. This was advantageous for the main-roof aesthetic, as no additional slate vents or dry-ventilated ridge systems were required.

Permavent were also asked to troubleshoot low-pitch roofing complexities on several elevations of the property. The installed roof pitches are as low as 12 degrees, and the addition of Permavent’s Easy Roof System enabled the specified roof slate to operate at this pitch. The main benefit for the client was no change to the traditional heritage roof aesthetic, complimenting the rest of the build, which was also a requirement by Building Control. All Easy Roof System roof areas achieve a comprehensive 40 Year Guarantee.


How Permavent products were installed

Installed as per Permavent’s fitting instructions and guarantee criteria. In accordance with good roofing practice and compliance with BS5534 & BS5250.


Accompanying materials

  • Canadian Glendyne natural slate 508mm x 254mm, Cadw & Snowdonia National Park approved
  • JB RED 50mm x 25mm batten
  • Existing clay ridges salvaged and installed
  • Lead flashing details renewed



Architect: DEP Architects, Bridgend

Merchant: Casey’s Roofing / LBS Building Supplies

Installer: Wales Roofing Solutions


Products used

Permavent APEX

Air Permeable Extra

  • Air and Vapour permeable membrane
  • Integrated Tape (untaped option available)
  • No need for ventilation

Easy Slate

Low pitch system for slates

  • Unique breathability and condensation control
  • Extends the life of the roof by keeping battens dry
  • Creates new areas for slate application
  • Pitch as low as 12°

Permavent DRY

Indestructible Breather Membrane

  • Condensation control system
  • Ultra Strong

Permavent Permalap

Single Sided Tape

  • High adhesion
  • Ideal for roofing applications
  • Membrane repair tape