Alumasc Exterior Building Products Ltd has been a major force in the UK Construction Industry for over 30 years. During that time Alumasc products and systems have been specified on some of the most prestigious buildings in all sectors, throughout the UK. Highly regarded brands such as Harmer, Apex, Derbigum, ZinCo, Hydrotech, Armaseam and M.R., together with Alumasc's well known architectural rainwater range are leaders in their respective fields.