Cottage Retrofit Using Thermal Plaster

Cottage Retrofit Using Thermal Plaster

Cottage Retrofit using Thermal Plaster 


Listed Heritage Magazine Feature 

Project Type: Cottage Refurbishment

Project Name: Glen Cottage

U-Values: U Values improved from the existing solid sandstone wall of approximately 2.5W/m2K to 0.45W/m2K

Date: February 2018

Inspired by a vision to sympathetically restore their cottage using natural materials to insulate the solid stone sandstone walls and maintain the ‘breathability’ of the building.


This Cumbrian project was inspired by a client’s vision to sympathetically restore their cottage using natural materials to insulate the solid stone sandstone walls and maintain the ‘breathability’ of the building.


The house was the home of the late Workington based artist, Percy Kelly and his wife Audrey James, from 1958 to 1970.  Glen Cottage features on The Allonby Trail on the Percy Kelly website.  The cottage was portrayed in his paintings and visitors to the project can view Percy and Audrey’s initials etched on their bedroom wall, uncovered during the renovation.   We’re sure you’ll find this little cottage so inspiring that it will be top of your holiday list, as it will be available for let as soon as the work is complete - what better place to enjoy the dramatic West Cumbrian coast beaches than from this fabulous artist’s home!

Project Description

Ecological Building Systems worked in collaboration with the property owner to develop a cost-effective, permanent eco-friendly solution to renovate the existing dilapidated, damp, cold solid sandstone Cumbrian coastal cottage by upgrading the property internally with breathable insulation and providing effective insulation and durable weatherproofing externally.

Ecological Products Used:

  • Diathonite Evolution: lime and cork based, eco-compatible plaster used for thermal insulation internally and externally. Learn More

  • Diasen Watstop: epoxy waterproofing used internally and externally as a water barrier for partially underground wall. Learn More

  • Diathonite Deumix Plus: lime and cork based thermal insulation plaster used internally for dehumidification (rising damp) at the wall to slab junction (also performs as a salt barrier) Learn More

  • Diasen BKK Eco: applied externally as water repellent agent to reduce water absorbance of adjacent to the external wall elements (concrete path) Learn More

  • Argacem: lime based breathable semi-smoothing finishing thin plaster used internally Learn More

  • Diasen D20: water-based primer used over Diathonite Evolution to prepare the external surface for Diathonite Cork Render finishing Learn More

  • Diasen Aquabond: primer used on timber lintels, conduits etc, to prepare surfaces for effective adhesion to Diathonite Evolution Learn More

  • Diathonite Cork Render: eco-friendly coloured cork finishing coat, both water repellent and anti-fungal, to finish the exterior Learn More


Additional Information:

Conservation & Heritage Journal - Thermal Plaster Tackles Damp & Thermal Performance 

Cumbrian Life Magazine - Percy's Legacy 



Open Day Glen Cottage, Allonby, Cumbria, CA15 6PU
Diathonite Thermal Plaster