Discussing the merits or otherwise of solid walls could be right up there with watching paint dry, or maybe not? Changeworks’ Solid Wall conference explored the barriers to insulating a solid masonry walls to find out. 

Almost 200 attendees with an interest in the future of old masonry gatherred. Aside from Pink Floyd concerts circa 1979 and certain events in Berlin in 1989 walls don’t usually spark great public interest. Would Edinburgh 2012 go down in history as the start of a revolution challenging the orthodoxy that ‘old house’ means ‘cold house’?

Nick Heath of Changeworks kicked things off by spraying graffiti over a rather nice sandstone wall, outlining the issues and challenges that Scotland’s older walls face. Luckily for Nick this was a virtual wall on PowerPoint because next up was Historic Scotland’s Roger Curtis, solid wall enthusiast extraordinaire. Roger explained the dynamic nature of older walls as they adjust to changes in temperature and humidity (download presentations part 1 and part 2). They are also much more energy efficient than the estimated U value that software programmes indicate, an idea expanded on by Dr Caroline Rye from The Society of the Protection of Ancient Buildings.  But they still have problems, not least the ravages of Scotland’s climate, compounded in many cases by poor maintenance.  As Joseph Little from Building Life Consultancy explained, damp walls suck (or have a high ‘A value’ to the technically minded) and impairing this movement of moisture can dramatically reduce thermal performance. 

So, lesson one: look after your walls and they will look after you.

What became clear is that there many types of solid wall and we only understand some of them. Whilst many solutions exist, these need to consider both the type of wall and occupants’ needs.  Chris Thomson from Castle Rock Edinvar outlined an innovative approach involving replacing historic windows and insulating the remaining area with blown beads. The new windows got most of the credit from a delighted tenant, who benefited from a solution that, whilst expensive, was non-disruptive.

Lesson two: thermal comfort is as important as climate change targets. Furthermore, we shouldn’t be looking at walls in isolation.

We had presentations from Kingspan Insulation and the Solid Wall Insulation agency, but it became clear that this technology is still developing. The key is picking the right solution for the right wall. This was explained by Wilson Shaw of BCA insulation who noted that although slim line space age materials (for example Spacetherm) perform well, they are expensive. Furthermore they are only as good as the specification and installation.  In this respect, several concerns were raised about the objectivity and qualifications of Green Deal assessors.   

Solid wall insulation seems much more developed and ready for wider roll-out. But for blocks you need everyone on board to avoid the dreaded ‘Battenberg effect’ (see pic, now the cake makes sense!) One way off getting round this problem is through cheap or free insulation.  Russell Ogg from Energy With Ltd has started a company which aims to get utilities to pay for this.  Despite mastering the fiendishly complex Community Energy Support Programme (CESP) Russell was unable to explain how this would work as part of the Green Deal because DECC had yet to explain the ‘rules of the game’.  

Lesson three: given this uncertainty there won’t be an October revolution in the solid wall market.

Perhaps a short delay isn’t a bad thing, given the uncertainty the conference unearthed and the need for the more holistic approach which Chris Morgan of Locate Architects outlined. 

Lesson four:

More research is needed, as is training for advisors, because caution is needed when messing with old masonry in a damp climate. 

Lesson five: 

Better that the ‘Green Deal’ is a damp squib at first than the harbinger of thousands of damp walls across Scotland. Like the old walls themselves we need solid dependable solutions that will stand the test of time.

Download part 1 and part 2 of the presentations from the Solid Wall Insulation Conference.