http://www.bungoblog.com/general/back-lanes-meeting-outcome/

The option preferred by the lanes affected by the consolidation works (thus far – consultation closes on Saturday) is the cheapest and if this remains the case, when we report back to the Council we will be asking them and Forkers if it will be possible to extend the works to cover neighbouring lanes unaffected by the ground consolidation works. We will, of course, then meet with those residents to discuss the proposals.

I live in the neighbourhood, but people are probably not aware of my professional background. I’ve got a degree in architecture and two in civil engineering, the master’s concentrating partly on building science. Building science is the study of the passage of moisture and heat through building envelopes (the roof, walls and foundation). I’ve worked as a structural engineer and in building evaluation, as well as in building sector public policy. So, I’m well qualified to comment on this.

I’m from the Great Lakes region, which is a cold climate, much colder than Scotland in the winter and hot/humid in the summer. We had government programs in the 1970s that subsidised the addition of loft insulation to existing houses, both in the northern US and in Canada. In the 1980s, home inspectors started to notice rotting roof rafters. It wasn’t uncommon for the damage to be so bad that the roof structure needed to be reinforced or replaced.

The problem was that when the loft insulation had been added, inadequate ventilation was provided. When a loft is insulated, the space above it, included the underside of the roof, are much colder than the building below. However, unless a tight air barrier is added (difficult to do in an existing building, especially if loft access is to be maintained), moist air passes from the living areas into the loft. When this warm, moist air hits the cold rafters and boards, it condenses. The underside of the roof structure becomes damp, and mould and rot grow. After 10-20 years of this, the roof structure can be ruined. I’ve seen this myself in building inspections.

The amount of ventilation needed to prevent this is considerable: new houses with highly insulated lofts in the Great Lakes region are now built with continuous ridge and eave vents. This also prevents the snow that collects on the roof from melting and forming ice dams.

Although the winters here aren’t as cold as they are at home, I think that condensation might be a issue here as well, especially with the roofs of older buildings. It’s also worth noting that many of these buildings have cisterns in the lofts that are open to the air and still in use. The growth of rot and mould could affect the quality of the water in the cisterns, as could fiberglass dust (from the insulation) in the air. Roof and cistern access are issues as well; if the insulation is ticker than the attic joists (and I’m pretty sure it will be), then it may become difficult to reach to roof access and the cisterns.

I’m a greenie, but I’m also a preservationist. Adding insulation to old buildings can be problematic and shouldn’t be done without due consideration. According to Scottish Power, tenements and terraced houses are already more energy efficient than newer buildings. In my opinion, good ways to improve their efficiency would include adding a sealed layer of insulation to wall nooks and under window openings, making windows and exterior doors more airtight, and switching to compact florescent lights. I wouldn’t super-insulate the lofts without first addressing ventilation, access, and (if applicable) cistern access and water quality – and once that’s done, there goes the “free” insulation.

I am compiling an extensive database of Strathbungo properties and their residents – more to follow on this website one day, hopefully. @Michael Georgiades