Here are some links which you might find useful.

Certass
www.certass.co.uk/homeowners-2/

Global Roof
www.synseal.com/global-roof

Neighbourhood Watch
www.ourwatch.org.uk

PatioMaster
www.patiomaster.co.uk

Pilkington
www.pilkington.com
 

QA National Warranties
www.qanw.co.uk/consumers/

Energy Saving Trust
www.energysavingtrust.org.uk

The VEKA UK Group
vekauk.com