These are a few sites that you may find useful

Fensa The industry standard for replacement windows and doors

http://www.fensa.co.uk/

Building regulations

http://www.planningportal.gov.uk/england/professionals/en/1115314110382.html

Trade Organisations Bodies


British Cement Association (BCA)
http://www.bca.org.uk/

British Precast Concrete Federation (BPCF)
http://www.britishprecast.org/

Builders Merchants Federation (BMF)
http://www.bmf.org.uk/

Chartered Institute of Building (CIOB)
http://www.ciob.org.uk/

Concrete Society
http://www.concrete.org.uk/

Confederation of British Industry (CBI)
http://www.cbi.org.uk/home.html

Copper Development Association (CDA)
http://www.cda.org.uk/

Federation Of Master Builders (FMB)
http://www.fmb.org.uk/

Institute of Roofing (IOR)
http://www.instituteofroofing.org.uk/

Lead Development Association
http://www.ldaint.org/

Lead Sheet Association
http://www.leadsheetassociation.org.uk/

National Federation of Builders (NFB)
http://www.builders.org.uk/

National Federation Of Roofing Contractors (NFRC)
http://www.nfrc.co.uk/

Timber Research and Development Association
http://www.tradatechnology.co.uk/