“Newly built homes are more energy efficient than ever, the government said this week. But thousands of buyers are finding that their expensive new homes are cold and draughty with heating bills far higher than expected. The culprit? The finger of blame is pointing towards builders rushing to meet targets, lax standards and poor inspection, with badly installed dry lining at the heart of the issue.
Dry lining became popular in the UK in the 1980s, replacing traditional “wet” plastering with ready made plasterboard attached to walls and ceilings. It means plastering can be done in a couple of days rather than weeks.
There is nothing intrinsically wrong with dry lining, which is used commonly in Scandinavia and North America, where winter temperatures drop far below those of Britain. It gives a smooth finish and can be decorated straight away.
But what thermal imaging surveyors and other building experts are discovering is that widespread poor installation of plasterboard has resulted in the airtightness suffering badly.
Housebuilders rush to meet targets (their own and the government’s), often cutting corners, and airtightness suffers as a result. The plasterboard is attached to masonry with adhesive. But Paul Buckingham, a thermal imaging surveyor, says housebuilders often cut costs using “dot and dab” adhesive, rather than solid dabbing.
Thermal imaging often finds air pockets behind plasterboard walls, causing cold spots and reduced thermal efficiency.
“We don’t see any of this airflow in old houses,” he says. “In those built in the 60s and 70s, with concrete floors, the airtightness is pretty good.” (However, they may leak air elsewhere – through open trickle ventilators or fireplaces.)
Going even further back, case studies undertaken in 2011 by energy consultant Diane Hubbard found that most of the houses built before 1900 were more airtight than expected, and in some cases better than required by the 2006 building regulations, and “modern extensions may not be as airtight as the original building”. ….”