Case Study

The Easy Roof System allowed contractors to refurbish the roofs of 3 historic barns, while maintaining the original aesthetic and low pitch.

Woodhouse Farm, Shropshire Homes

This project comprises a refurbishment of 3 historic barn buildings, forming part of a new residential development on Woodhouse Farm in Shropshire.

To obtain planning permission, the developers Shropshire Homes Ltd were instructed to completely renovate the Woodhouse Farm barns on the property and ensure that the new roofs maintained their original aesthetic.

Utilising Permavent’s patented Easy Roof System, the contractor was able to install natural Welsh slates as part of a challenging roof design.
Elevations included roof pitches as low as 21 degrees, normally well below the minimum pitch guidance set out BS 5534: 2014 + A2: 2018: Slating and Tiling for Pitched Roofs and Vertical Cladding.

However by selecting Permavent Ltd’s Easy Roof System, Roofrite (Shropshire) Ltd were able to satisfy the terms of planning by installing Easy Slate seals, which are compatible with natural and fibre-cement slates and can be applied as low as 10 degrees* whilst remaining compliant and satisfying the terms of the planning permission.

Permavent’s air and vapour permeable APEX membrane was also specified within the design of these new roofs. Permavent APEX was approved because as per BS 5250:2020: Management of Moisture in Buildings and NHBC guidance, air and vapour permeable membranes do not require additional ventilation at high or low level.
Therefore, modern forms of ventilation such as plastic slate-vents could be removed and the traditional appearance of the roof could be preserved.

*Please contact our sales and technical team to confirm compatibility with different brands of slate.






Woodhouse Farm, Priorslee, Shropshire.


In order to comply with the planning permission instructions, Shropshire Homes Limited had to fully renovate 3 historic barn buildings while maintaining the original aesthetic of the buildings. This included a low pitched slate roof that required the use of the Permavent Easy Roof system.

Why Permavent Was Chosen:

Permavent Easy Slate was specified on this project as it is the only approved solution which addresses the issue of water ingress that often occurs on low pitched slate roofs. Furthermore, due to the unique technology of the Easy Slate system the roof could be installed at low pitch in conjunction with natural Welsh and Spanish slates, which carry their own unique aesthetic that allowed for complete compliance with the planning stipulations.
Easy Slate has the added benefit of being the only solution which protects the roof by keeping the batten dry and protected from wind driven rain or snow. When combined with the air and vapour permeable properties of Permavent APEX, this provided the contractor with a complete, approved and compliant solution from a single supplier which streamlined and simplified the purchasing of roofing materials. Consequently, the client is also eligible to achieve Permavent’s comprehensive 40-year Easy Roof System guarantee for this project. 

Ross Jones, Project Leader and Manager of Roofrite (Shropshire) Ltd. said:
We decided to go with the Permavent Apex underlay due to the style/age of the property and the limited airflow we were able to obtain. By using the natural slates and brick corbelled eaves, we decided to use the Apex mainly due to its properties and not requiring the need of additional ventilation in the roof space. However, due to the lower pitch design of the roof, we decided on using additional ridge ventilation to limit condensation issues in future.  

After previously using the low pitch system for plain tiling, I was in contact with James Ford who discussed the use of the low pitch slating system and recommended to be used on this particular project. It was the first time that we have used the system and since then, we have used it on one further project and have quoted to use it on future jobs/projects.” 

 Permavent were also able to provide additional support on-site with industry leading technical advice and suggestions on the system installation. On top of this, our Sales and Technical team provided on site product toolbox talks to help familiarise the contractors’ operatives with the range of specified products. 


Roofrite (Shropshire) Limited
Unit 61
Atcham Business Park


Boden Roofing Supplies

Woodhouse Farm, Shropshire – Before Renovations

Woodhouse Farm, Shropshire – After Renovations

Products Used

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 10° with fibre cement slates

Permavent APEX

Air Permeable Extra

  • Air and vapour permeable membrane
  • Integrated tape (untaped option available)
  • BBA Certified
  • No need for ventilation