Floratec FS75 is a lightweight drainage and water storage board, manufactured from 100% recycled, CFC free, expanded polystyrene, used mostly in extensive and intensive green roof applications. The product allows aeration of the substrate; evaporation of stored water and multidirectional drainage on the underside. Can also be used on flat roofs, with little or no drainage and on sloping roofs up to 20°.


Install by loose laying directly onto the root resistant membrane (overlaid with a moisture resistant mat on sloped roofs only). The larger 75 x 75 mm box sections must be uppermost when installing on slopes, whilst the 35 mm diameter water storage holes must be uppermost when used in horizontal applications. Butt joint the boards together. Panels can be cut with a heavy duty knife or a small toothed saw to fit around protrusions. On horizontal applications overlay completely with an appropriate filter sheet and substrate. On sloped roofs, use the filter sheet at perimeters and around protrusions only.

Where slopes exceed 15°, a JEG anti-erosion mat must be used in conjunction with the substrate.

Standard product features




75 mm.

Panel size:

1 x1 m.

Maximum slope:


Dry weight:

0.7 kg/m².

Water storage capacity:

2 litres/m².

Compressive strength:

50 kN/m².

NBS Specification

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This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Alumasc Building Products Ltd


+44 (0)1744 648400

Product reference

Floratec FS75

Manufacturer details

White House Works,
Bold Road,
St Helens,
Merseyside, WA9 4JG
Tel +44 (0)1744 648400
Fax +44 (0)1744 648401
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