Polyfoam Slimline Zero Membrane

Polyfoam Slimline Zero Membrane

For protected membrane flat roofs


The use of Polyfoam Slimline Zero Membrane improves the thermal performance of protected membrane flat roofs by reducing the amount of rain water flowing between the insulation and the waterproofing membrane.


Polyfoam Slimline Zero Membrane is a high performance, thermally bonded tri-laminate of polypropylene; spunbonded (outer layers) and microporous (inner layer). It is used in combination with Polyfoam Roofboards as part of the Polyfoam Inverted Roof System for inverted and green roofs.


  • Improves the thermal performance of inverted and green roofs
  • Waterproof and water vapour permeable
  • Enables thinner insulation and less ballast to be used
  • For full application details please refer to BBA certificate 17/5454


Polyfoam Slimline Zero Membrane is used as a separating and water flow reducing layer (WFRL) in low moisture impact inverted and green roofs. The water resistant properties of the Polyfoam Slimline Zero Membrane result in it reducing the flow of water through the roof construction. This means that the impact on thermal performance by rainwater cooling is largely negated.

Inverted and green roofs incorporating Polyfoam Slimline Zero Membrane are lighter as less ballast is required. This is due to a vastly reduced floatation impact as more drainage occurs above the insulation than below it. For full application details please refer to BBA certificate 17/5454

The use of Polyfoam Slimline Zero Membrane offers superior thermal performance – so by using the same thickness of Polyfoam Roofboard you can achieve superior U-values.

Water resistance

Polyfoam Slimline Zero Membrane is able to resist a 1.50m head of water.

Handling and storage

Polyfoam Slimline Zero Membrane is easy to handle and install and can be cut with a knife or scissors.

Polyfoam Slimline Zero Membrane is supplied in rolls in polythene packaging and is labelled with identifying product and manufacturing data.

Polyfoam Slimline Zero Membrane may be stored flat or upright on a clean, level surface and should be kept under cover.

Product Data

Length (m)Width (m)Area per Roll (m2)
PropertyTest methodUnitData (kPa)
Tensile strength in MDEN
N/5 cm185
Tensile strength in CDEN
N/5 cm130
Nail tear resistanceEN
N/20 cm55
20cm folded MD/CDprEN
N/20 cm65
Water resistanceEN 20811m of water
Water vapour transmission
(23ºC/85% humidity)
UV stability under constant
prEN 1297-Up to 4