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Polyester Flat Roofing...

Polyester Roof System

Nordgum Polyester Flat Roofing System

Waterproofing membrane made of Polymer elastomer modified bitumen (SBS) and reinforced with a non woven polyester carrier. The compound is a mixture of distilled bitumen and thermoplastic rubber which is Styrene Butadiene Styrene (SBS). The bottom surface is covered by a poliethilene burn off film.

Two finishes are available

NORDGUM (plain) available in 3mm, 4mm and 5 mm thickness or 4 Kg/m2 and with upper surface covered with sand or poliethilene burn off film on request.

NORDGUM MINERAL available in 4 Kg/m2 and 4,5 Kg/m2, with upper surface covered by natural slate granules in order to protect the membrane against U.V. radiations.


Polyester Roof System

NORDGUM is one of the most convenient solutions for roofing renovation work and general waterproofing. Nordgum achieves good values of mechanical resistance thanks to the non woven polyester carrier and excellent low temperature flexibility that permit it to be used in difficult climatatic conditions.







Membranes are particularly well suited for the waterproofing of structures which may be subjected to limited movement or dimensional changes such as: -

  • Flat, sloping and pitched roofs
  • site cast reinforced concrete
  • prefabricated concrete
  • masonry cement
  • metal and laminated wood deck terraces
  • foundations
  • antiseismic foundations
  • car parks
  • stress structures
  • tunnels
  • underground railways

The high degree of elasticity and flexibility allow the use in conjunction with elastomeric and polymer plastomer modified membranes which are reinforced with non woven polyester fabric, and the use as complementary layer in a two layer waterpoofing system.

Nordgum Website

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Applications instructions: The application of the membrane is by torch bonding using a suitable propane gas torch. Other tools include a knife and a trowel with a rounded end. Depending'bn-th.e structure and the specification the membrane may be partial or spot bonded, loose laid or fully, bonded.

When deciding on the system to use refer to our Specifier's Guide leaflets. The membrane should be applied to the substrate using a propane gas torch; this is used to burn off the burn-off film and melt a thin layer of bitumen while unrolling and laying the membrane. For a "spot bonding" installation, apply the flame only to those areas of the sheet to be bonded to the substrate making sure that the bonded areas are evenly distributed.

All membranes must be laid to allow side laps of 80 mm and end laps of 150 mm. If the membrane is only partially bonded remembel; that'll bonding must always take place for 1 meter each side of the end laps. Finally, SBS modified bitumen membranes can be used as exposed cap sheets only if the membrane ifr self- protected by mineral slate granules.

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