The Roof Group
California based commercial roof management and consulting firm specializing in inspections, maintenance, repairs, construction management.
http://www.theroofgroup.com/

Roof Genius
Roof calculator, calculates a detail list of roof materials, and a complete estimate. Two ways to determine roof pitch. Offers tips and how to's on roofing. [Windows 95/98/2000/Me/XP/NT]
http://roofgenius.com/

The New England Slate Company
Vermont Company supplying slate roofing for the repair, restoration and construction of a natural slate roof.
http://www.neslate.com/

Decra Roof Systems:
Roof coverings using lightweight roof tiles for all roofs down to a ten degree pitch. UK.
http://www.decra.co.uk/

UK Aero
Helicopter Repair specialists, Tailboom Reskins,major structural repairs,FAA DAR,UK Aero,FAA DER,Roof & box beam
http://www.ukaero.org

Roof Products, Inc.
Manufacture prefabricated roof curbs and other roof accessories. Products include expansion joints, equipment supports, adapters, and ice deflectors.
http://www.rpicurbs.com/

Roof Coatings Manufacturers Association
Roof Coatings Manufacturers Association (RCMA) represents manufacturers of cold-applied roof coatings and cements. RCMA’s site offers product information and the latest roof coating news.
http://www.roofcoatings.org/

Milligan Construction
Milligan Construction LLC repairs, replaces and restores slate roofs, copper valleys and flashing. Our specialty is high quality slate repair.
http://www.milliganconstruction.com

Fibreglass Roof Decking
Roof Decking From Dura Composites Ltd
http://www.roofdecking.co.uk

American Hydrotech, Inc.
Hydrotech’s Green Roof, the Garden Roof Assembly is the latest innovation in roofing/waterproofing using MM6125 and 40+ years of successful installations around the world.
http://www.hydrotechusa.com/