Part C is about ensuring that the site for new buildings is prepared in a manner that will promote resistance to contaminants and moisture for the structure that is to be built on the site.
As of the date of writing, Part C was last revised in 2010 as a result of the Building Regulations 2010.
There are a number of subjects that fall within this part of the regulations. These include weather and water tightness, drainage and measures to deal with contamination and hazardous substances such as radon and methane.
Part C Site preparation and resistance to contaminants and moisture contain the following high-level requirements:
- C1 Preparation of site and resistance to contaminants
- C2 Resistance to moisture
There are three key aspects in the preparation of the site – that the site to be covered by the building & associated land is free from materials that might damage the building such as pre-existing foundations or vegetable matter, be free of contaminants and provide adequate drainage.
The regulations provide helpful information related to undertaking a risk assessment of contaminants and a high-level overview of some of the remedial measures that are available.
One potential contaminant that we all need to consider when building is radon. It’s not a major issue in most of the UK; the south-west is the area most at risk, but one we all need to consider. Start on the British Geological Survey website.
The second part of the regulation, that dedicated to discussion of resistance to moisture contains useful information related to site surveying, subsoil drainage and the construction of resistant floors, walls & roofs. A useful map confirms what we knew all along, that most of Wales is exposed to very severe driving rain. What would we in Wales do without the blessed rain…?