13th July 2015…..The Zero Carbon dream, the Green Deal, eco-positivity and manufacturers – all have contributed to a message that says if you envelope buildings with either silicone or acrylic rendered external wall insulation, you are freeing residents from heating bills, damp, condensation and mould. It’s a hey presto magic silver bullet! Wah-hey! Right? No. As so often happens, the downside emerges into the expensive light of regrets…..and not before.
Increasing numbers of people complain that it is hotter inside than it is outside in warm weather and that they cannot cool their homes down by any means. Having to install air conditioning and use fans to counteract stifling heat buildup that cannot escape at night from behind the EWI is not any kind of zero carbon dream and it means using electricity you would not otherwise have to use. Articles reporting scientists’ findings and concerns appeared recentlyin the Daily Mail and This is Money. Trapped heat putting lives at risk was in May and Homes to ovens – lethal risk last week. Please read them. People in single aspect dwellings already suffer from lack of cross-ventilation and are at greatest risk in buildings clad with EWI, along with those living in high rise flats facing south.
If you wore a latex catsuit out in 25 C or 75F sunshine or wrapped yourself in a duvet coat to sit out in hot summer sunshine, wouldn’t you expect to get wet and damp inside that duvet/catsuit? So it is with buildings. And EWI is, effectively, a duvet; and the render over it is a seal to prevent moisture getting into it – so interior moisture can’t escape through it either. It works both ways. Plus, if the EWI went onto a less than perfect surface, and was not kept bone dry until over-rendered, the trapped moisture can begin to damage the building from within.
Condensation and mould
There have been too many reports of condensation and mould appearing after EWI has been put onto buildings which were previously dry and mould-free. It forced the Scottish Government to commission a report. This was published December 2012, exonerates EWI, speculates about installation issues and blames residents for not knowing how to use their homes. And now BRE Wales has put out a call for evidence for as they find cause to investigate this phenomena in Wales.
There is a growing body of references and literature concerning the downside of EWI.
- The Risky Business of Covering up – Joe Malone, surveyor
- Unintended consequences -Robert Hine, leading building specialist
- Surveying property, guest article on EWI – Joe Malone, surveyor
- The risk to housing from overheating – BRE
- Defining overheating/thermal comfort – BRE
- Indoor Air Quality concerns & issuesin highly insulated bldgs – NHBC Foundation
- Report on Failure Rates and Remediation costs for External Wall Insulation and Cavity Wall Insulation – BRE
Water gets its wicked way
Where water gets under the render, or the EWI/render combo are slapped onto an imperfect building some very unsightly staining occurs – tide marks even! And the guarantee is invalidated.
At Lancaster House on the Kingsway in Hove, brickwork was rendered just a few years ago. Not exactly waterproof render, is it! These photos below were taken on a bright sunny 19th January 2015 day when there had been no rain for a few days. There is no EWI under it.
These two examples above are less than successful retrofit strategies addressing whatever and looking to extend the life of these buildings.
Newbuilds, however, are prematurely ageing where EWI and silicone or acrylic type renders are used on them. Within just a few years they acquire that, je ne sais quoi, banana-republic look.
Below is the greying and stained 1-3 Vallance Gardens on the Kingsway, which is only 5-6 years old. Cream was chosen as white was thought to look dirty too quickly. All these self-coloured renders are sold as maintenance-free and they are not. This nice design, right for the seafront, looks grubby. The van Alen is the same. And I hate to think what it costs to periodically de-stain it and bring it back to its newbuild loveliness.
That ‘poor look’ that has no cachet (but DAMN, didn’t it cost!)
And here is what is happening to the textured render at ‘My Hotel’ in Jubilee Street – again just a few years old. Classy!
EWI can mean incurring new costs and the payback period on retrofitting with it is higher than the potential lifetime of any building. This hits council housing leaseholders hard where EWI is being forced on them. On the Clarendon & Ellen Estate, some leaseholders gave flats back to BHCC, sold or rented their homes out and left to go who knows where – because the roughly £23,000 cost notified to each of them was not doable. Others have ceded part of their equity to BHCC to cover the cost – all without so much as a planning application in place.
One application has been refused, a 2nd goes to Planning on the 15th of July recommended for refusal. Several tenants have voiced opinions about preferring the brick and one who was shown the banana CGI below got quite upset, stared in utter disbelief; but none of them is willing to put head above parapet to give this view to the council. The council will do what it wants is their defeatist and cowed position. Elsewhere in the city council leaseholders are resorting to law – after the fact.
Without so much as a serious building condition survey, it is planned to remove the concrete roof, existing insulation and paving stones on top of all that to install “an overlay system” on all the towers of the Clarendon & Ellen Estate. No other explanation or documentation. Just “overlay system”. An independent surveyor and the builder who commissioned him on behalf of a group of leaseholders cannot see the justification for taking out the existing roof they examined on top of Clarendon House. Mears don’t care. And BHCC doesn’t care. The mast climbers are up and they are already dismantling the Conway Court roof covering. Getting on with spending their £6.4m budget. And this too is deterring comment on the application – especially as Mears is already up and at it and pumps out paperwork about their progress…..
This is what is planned visually:
Then there is the carbon capture angle. BHCC is anxious to reduce its carbon footprint and has a roll-out programme in place to slap EWI on all its housing stock (which also requires replacing windows to put in new that will overlap and make a seal over the EWI). The biggest carbon capture freebie going is a mature tree! Instead of the bi-annual hard pruning of street trees so they look like loo brushes, shouldn’t street trees be allowed to branch away so they can suck up all the carbon? Shouldn’t there be a council tree policy that treats every mature tree as carbon-capture gold dust? Here is the science!
There is even a YouTube video of EWI cladding falling off Stanley House, a high rise building in Bootle in the Midlands. It happened in 2006. Reading one of the Malone references above, it is clear attachment method really matters. On the Clarendon & Ellen Estate the bricks are just outer decoration in front of a cavity behind which are concrete panel walls. Glueing and bolting through all that is what the site manager says is going to be done but there is nothing in the planning application about affixing. Reading Malone, it is clear this needs SERIOUS consideration, especially at the top of the buildings….
Progress….you have to know what is and isn’t actually ‘progress’. And you have to do your homework and you have to look at planning applications with care. It is so imp0rtant not to shy away from involvement with the planning process; and the fact that Mears and BHCC consider their planning applications don’t have to wait for approval (and assume there will be no interference with plans) sets a disgusting example to the public and shows absolute contempt for the planning system. Shame on them.
NB. Since this article was written, the planning application for EWI cladding of the Clarendon & Ellen Estate in Hove has been refused for a second time (15 July 2015). New applications were submitted for just window/balcony doorset replacement and consented; and, in February, 2016, an application was registered for a mixture of works, including masonry repairs, with a claim in the application form that work had not begun, even though both Conway Court and Clarendon House had their masonry part-drilled out in the autumn of 2015 and left open to the elements over the high salty winds/rain-sodden winter. Instead Mears turned its attention to removing bricks and sucking out all the cavity wall insulation…go figure.