Building Regulations, Approved Documents Part D – Toxic substances

Part D is about ensuring that there is no risk to the occupiers of a building from toxic substances used in its construction.

As of the date of writing, Part D was last revised in 2010 as a result of the Building Regulations 2010 and Building (Approved Inspectors etc) Regulations 2010.

Part D Toxic substances contains the following high-level requirement:

• D1 Cavity Insulation

This is a short document, of limited relevance to historic building convertors as the requirement contained in the document relates to cavity walls. In the UK, cavity walls only became a common template for wall construction in the 1970’s and a requirement of building regulations in the 1990’s so a wall cavity is absent from most older buildings.

In short, the regulations state that where and insulating material is placed in a cavity, reasonable measures must be put in place to ensure that no toxic fumes are able to permeate into any occupied parts of the building.