Tailored EWI solution developed for Cornish Unit refurbishment

RCT Homes, Wales largest social landlord, has specified a ROCKWOOL External Wall Insulation (EWI) system for the refurbishment of 30 Cornish Unit Homes to overcome prevailing thermal issues. Buildingtalk’s Video of the Week looks at how the homes were insulated to meet current modern day regulations.

Cornish Unit Homes were created as a temporary solution to the post-war housing crisis following World War II. Many of these homes are now over 50 years old and no longer meet the modern day requirements and the minimum standard of social housing decency that RCT Homes has to uphold.

Due to their complex structure, RCT Homes was required to provide a very different approach to the whole house structure when the refurbishment began in mid-September 2015.

The ROCKWOOL insulation solution

Working in conjunction with Hirwaun-based building contractor, Thomas Holdings, RCT Homes contacted ROCKWOOL to provide a tailored solution, being trialled for the first time at the development in Cwmbach, before it is offered to the wider market.

Cornish Units are very different to typical housing assembly due to their contrasting ground floor and first floor structure, and protruding windows and mansard roof. This meant that ROCKWOOL Architectural Design Consultant, Lewis Ham, had to design a unique technical approach to insulate the buildings.

The final solution featured a combination of its REDArt External Wall Insulation System (EWI) on the ground floor with ROCKWOOL FLEXI on the first floor. This enabled ROCKWOOL to resolve the building’s thermal issues without comprising the iconic look and style.

REDArt & FLEXI

REDArt is manufactured from stone wool insulation and has been developed to be installed on a wide range of substrates and wall construction types. Renowned for its thermal and fire protection properties, the use of REDArt allowed contractor Thomas Holdings to fix the insulation to the ground floor with minimal disruption to the occupants. 

ROCKWOOL FLEXI, a multi-use, dual purpose thermal and acoustic insulation solution, was chosen specifically for the upper floor structure for its unique flexible edge. This patented feature ensures that the insulation is fixed and maintained perfectly between the product and its supporting framework for both easy installation and optimum effectiveness. 

The specification of ROCKWOOL FLEXI was vital due to the building’s challenging design and timber frame structure – which also benefits from the insulations Euroclass A1 fire properties. 

Used together, REDArt and FLEXI provided a tailored solution specifically designed for Cornish Units that achieved the required whole house approach to resolve all thermal issues, as well as achieving optimal acoustic performance and fire resistance combined with outstanding environmental credentials and easy installation.

Mike Kelly, company director at Thomas Holdings, commented: “ROCKWOOL performed above and beyond our expectations on this project. Working with a renowned difficult housing design, and with no previous or similar insulation refurbishment plan available, ROCKWOOL provided us with a brand new technical approach to insulate the houses, whilst adhering to the buildings unique style and structure. 

ROCKWOOL’s optimal thermal and fire resistance combined with its outstanding environmental credentials and easy installation made ROCKWOOL REDArt® EWI and ROCKWOOL FLEXI® the ideal products for this project.”

Contact:

ROCKWOOL,
Pencoed,
Bridgend,
United Kingdom,
CF35 6NY

Phone: 01635 862621
Fax: 01656 862302

Visit the ROCKWOOL website

Visit Supplier's page