Saint-Gobain Weber External Wall Insulation Upgrades Leicester

Published by Jackie Biggin for Weber in Housing and also in Communities

Victorian solid wall properties in selected areas of Leicesterare being treated to a whole house upgrade to improve thermal performance.  The award-winning and versatile External Wall Insulation (EWI) system by Saint-Gobain Weber, the leading formulator and manufacturer of innovative materials for the construction industry, has been applied to the rear of the dwellings and finished with a brick-effect render to match neighbouring properties.

In this location, with the hard to treat properties opening directly onto the paved street, local planning restrictions have overruled any measures that could impinge on the already narrow frontage.  This requires a hybrid approach to insulation with EWI applied to the rear and Saint-Gobain Celotex PIR insulation applied to the interior walls of rooms at the front of the terraces.  Other measures include insulation to lofts and floors, boiler and radiator upgrades or replacement, the introduction of smart gas fires to replace old electric wall heaters, and draft proofing throughout the two-storey terraced homes.

Managed by asra Housing Group, 175 properties in the Belgrave, Cossington and Maynard Cooperative housing associations have been selected in the 10-week pilot scheme. Properties in the Ross-Walk Cooperative will be treated in 2013.  asra Housing Group, which prides itself on providing culturally sensitive services to diverse communities, manages more than 12,000 homes in theMidlandsand South East England.

“Each Cooperative is empowered with its own committee and is self-governed by its residents,” says Imtiaz Vohra, asra agency manager for the Cooperatives, “and we are proud to be managing this project and working so closely with the tenants and the applicator.  Even before these upgrades are fully complete we are receiving welcome reports that the buildings are already warmer and more comfortable, while problematic condensation is practically eliminated.”

Network Weber recommended Well Warm, of Leicester, is carrying out the extensive project.  “This will be a blueprint for upgrades of this type across the country,” says Arron Cooper, director, Well Warm.  “Our applicators are enjoying working with the Saint-Gobain Weber EWI system and many of them have attended an up-skilling course arranged and hosted by Saint-Gobain Weber atLeicesterCollege.”  Well Warm is SWIGA (Solid Wall Insulation Group Agency) backed, and BBA Green Deal Installer approved.

The weber.therm XM EWI system with weber.rend RB achieves striking results.  It produces a superb brick look-alike finish in just a fraction of the time and cost of full brickwork cladding.  weber.rend RB is the combination of two polymer modified mortars used in conjunction to create an authentic brick work pattern.

The weber.therm XM EWI system using 90mm thick grey expanded polystyrene (EPS) is mechanically fixed to the brickwork substrate with meshcloth reinforcement incorporated between two coats of weber.rend LAC, a polymer modified powder cement-based render mortar.  Once set the surface is lightly comb scratched prior to the application of weber.rend RB base render coat which acts as the ‘mortar’ joint.  When the weber.rend RB base coat has taken up and is firm enough to allow application of the face coat, 2-3mm of weber.rend RB face coat is applied and stippled with a soft bristle brush to give the brick surface effect finish.  Eight colours of face render are available, allowing clients to replicate almost any brick and mortar combination which is important when matching with existing properties, and in this case selected walls on the same property. 

The brick pattern is achieved by cutting through the weber.rend RB face coat to expose the contrasting weber.rend RB base render.  Any brick laying pattern can be achieved including conventional cavity layout as well as header and stretcher bonding of traditional solid walls.  Correctly applied this system is often mistaken for high quality bricklaying, even by an experienced tradesman.  “weber.rend RB, used as part of the weber.therm XM EWI system, is transforming both the aesthetics and thermal efficiency of solid wall housing in this area ofLeicester,” says Jayshill Patel, area surveyor, asra Housing Group.  “It looks like a brand new brick house with the added benefit of massively improved thermal efficiency.”

In these homes the target U-value using the weber.therm XM EWI system with 90mm of encapsulated polystyrene insulation board is 0.30 W/m²K, a significant improvement from the original which in some cases was in excess of 2.1 W/m²K.  “Tenants are reporting warmer and more comfortable homes and the need to turn their heating down or only switch it on for short periods of time,” continues Jayshill.

The scheme has been welcomed by the local community who see it as a very positive move that will benefit many tenants experiencing fuel poverty.  It is funded by the Community Energy Saving Programme (CESP), the scheme designed to target housing in areas of low income to improve energy efficiency standards and reduce fuel bills, through EDF Energy.  Although the CESP scheme is due to close in December 2012, the remaining 500+ properties in the ASRA Housing Group upgrade initiative will be delivered during 2013 funded through the new ECO (Energy Company Obligation) programme with energy provider npower.

Tenant Mrs Yasmin Sidat commented: “This house was freezing and we often had the heating on all day but now we keep turning it down the warmer it gets.  And the new ‘brickwork’ has made it look brand new.  We are very pleased and we know our heating bills will be much lower which is very good.  We have been lucky to be included in this scheme.”

Well Warm is employing only local tradesmen, including plasterers, plumbers, gas engineers, painters and decorators and specialist applicators, to deliver this challenging project within a very restrictive schedule.  “Of course there are teething problems on a pilot such as this,” says Shaun Patel, site agent, Well Warm, “and when we need advice and technical support Saint-Gobain Weber will come to site, identify any problems and get us back on track.”  Basil Morris, applications manager, Saint-Gobain Weber, makes weekly site visits and is at the end of the telephone in the interim.  “This hybrid approach is exactly right for these properties and we will continue to come up with solutions to solve complex upgrade projects anywhere in the country.”

Further information and technical support is available from Saint-Gobain Weber on 08703 330 070, or 028 9335 2999 in Ireland, or visit www.netweber.co.uk.  A free download of the new weber.app for iPhone and iPad users is available from the iTunes app store, and from Google Play for android smartphones and tablets.