Isle of Harris

Wetherby Building Systems Ltd and IRS Scotland Ltd have embarked on a project that will see the Isle of Harris upgrade their pre-existing Swedish timber properties with renewed energy efficiency thanks to Wetherby’s external wall insulation systems.

By the end of World War Two there was a severe shortage of housing in Britain so in an attempt to overcome this, prefabricated homes were sourced from Sweden and exported flat packed to Scotland. Swedish Timber Frame properties are prefabricated sectional units that feature a Scandinavian design; approximately 4,500 were built in the UK in the post-war years of 1945 – 1951.  Although the majority are still in good use, their thermal inefficiency means they often have very low EPC ratings.

They were described as ‘permanent’ but even so were given a life expectancy of only 60 years. Since then many of these Swedish prefabs have been lost due to deterioration caused by climate, alteration, or demolition and those that have survived beyond their 60 years are severely lacking in appropriate energy efficiency.

IRS Scotland Ltd were appointed as main contractors and worked in partnership with Hebridean Housing Association and Scottish & Southern Energy to deliver an External Wall Insulation system suitable for these Swedish timber framed properties. After careful consideration Wetherby’s Rail Fix system was chosen as the ideal the solution for the project.

Wetherby’s BBA approved Rail Fix system incorporates a drainage cavity; by using this method it allows the steel frame structure to remain dry protecting the building from any potential weather damage, whilst allowing the frame to breathe. The 600mm wide ventilation channels helps the system reduce condensation and moisture within the property by allowing it to escape via the perforated starter track. Once complete the insulation could be installed followed by a reinforcing basecoat, anti-crack alkali resistant mesh and finished with 1.5mm Silicone ‘K’ Render to provide a flexible high impact finish.

This considerable improvement in thermal efficiency has enabled the properties to retain much more heat, making them a warmer and more comfortable space, as well as significantly reducing the resident’s energy bills. The aesthetic appearance has also been dramatically improved bringing the estate in line with modern standards.