Built-Up Roofing Systems

We can offer a wide variety of roofing, re-roofing and maintenance services within this Division.

Contracting in all types of Flat Roofing, we specialising in High Performance Membrane replacement coverings in the industrial and commercial re-roofing markets. We also have the capability to carry out small works domestic re-roofing to a very high standard.

WG Walker have been installing Built Up Flat Roofs in excess of 100 years with the company being founded nearly 200 years ago.

WG Walker have always been synonomous with quality installations and high performance products and are recognised and associated with the leading UK and European manufacturers.Our inhouse management team works in partnership with these manufacturers utilising our technical experience to design and install systems to meet clients build and design requirements.

Derbigum Installation Methods

Derbigum can be installed using five different methods, to meet varying needs, including
speed of application and site safety. Derbigum single layer applications achieve high
performance combined with rapid application and economy. Alternatively, Derbigum can
be applied as a high performance cap sheet in a built-up roofing system.

Membrane Application Methods

Torch Application

• Provides a fully bonded system suitable for all new and refurbishment projects

• Ensures direct and immediate adherance of the membrane

• Bonding is achieved by melting the lower surface of Derbigum by torching

• Set-up and installation can be done quickly and efficiently

• Where required, the substrate is primed using Alumasc Bitumen Primer

Cold Bonding

• A quick application method with no flame required, offering increased site safety

• Derbigum is rolled into fresh, cold applied Derbibond NT

• Bonding is achieved by melting the lower surface of Derbigum by torching

• The cold adhesive is either poured onto the prepared surface and spread using a squeegee or spray applied with an airless spray gun

Mechanical Fixing

• A quick and clean installation method that does not use adhesives

• Typically a vapour control layer is loose laid, with sealed laps, over the structural deck, insulation boards are then installed, mechanically attached

• Not suitable for tapered insulation

• Derbigum is installed over the insulation with side laps of 130mm and end laps of 150mm

• Mechanical fasteners are fixed within the lap through the insulation and into the deck

Information and pictures supplied by Alumasc Exterior Building Products