Firet fabric is a non-woven plastic fleece used in construction as a separation, drainage or protective layer. The name comes from the Dutch manufacturer Firet, formerly a major producer of non-woven textiles. The fabric is made of thermally bonded polyester or polypropylene fibres and has an open structure through which water can pass while sand grains are retained.
Properties
A Firet fabric has the following characteristics:
- Water permeable — moisture flows freely through
- Sand-free — fine fibre net holds grains back
- Strong — resistant to tension and friction
- Rot resistant — synthetic fibres do not decay
- Flexible — adapts to uneven substrates
- Easy to install — delivered on rolls
Application
Firet fabric is used in construction for:
Foundations and basements
- Protection of dimple foil against damage
- Drainage around basement walls — leading water to drain pipes
- Separation layer between sand and insulation
Roofs
- Separation layer between roofing and insulation
- Drainage on flat roofs with gravel ballast
- Protection of EPDM or bitumen roofing
Garden and paving
- Weed barrier under chippings or gravel
- Separation layer between soil and paving sand
- Drainage around gravel pits and soak-aways
Roads and infrastructure
- Geotextile in sub-base
- Filter around drainage pipes
- Stabilisation of soft substrates
Different qualities
Firet fabrics come in various weights (per m²):
| Quality | Weight | Application |
|---|---|---|
| Light | 80–100 g/m² | Garden, weed barrier |
| Standard | 120–150 g/m² | Drainage around foundation |
| Heavy | 200–300 g/m² | Road building, roofs |
| Extra heavy | 400–600 g/m² | Soil retention, geotextile |
A heavier fabric offers better tear resistance and longer life but costs more.
Difference from other materials
- Firet fabric — non-woven fleece, water permeable
- Foil — plastic, impermeable
- Geogrid — strong strip grid, for soil reinforcement
- DPC foil — diffusion-tight, prevents rising damp
Related terms
- Geotextile
- Dimple foil
- Drainage
- Vapour barrier
- Gravel pit
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