Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 16·3.10
Radon protection requirements for dwellings
New dwellings, alterations and extensions, and buildings converted to dwellings in radon affected areas must be protected from radon ingress in accordance with specified guidance.
In radon affected areas –
(a) new dwellings;
(b) alterations, extensions, conservatory and porch extensions (including exempt conservatory and porch extensions) to dwellings; and
(c) buildings converted to dwellings through a material change of use,
should be protected from the ingress of radon in accordance with paragraphs 3.11 and 3.12.
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