The right laminate flooring underlay protects a floating floor from damp, hides small bumps in the slab, softens footsteps and helps the joints stay locked. Choosing the wrong one is one of the commonest reasons click floors creak, swell or sound hollow. This page covers foam, foam with a damp-proof membrane, and acoustic rubber or cork for flats. Send one request and flooring suppliers and fitters near you quote you directly, supply only or supplied and laid. It is free and there is no obligation.
Types of underlay and what each is for
Match the underlay to the subfloor and the building:
- Basic foam: a thin polyethylene foam for dry, flat timber or well cured screed. The cheapest option.
- Foam with a damp-proof membrane: a built-in film, taped at the seams, for concrete slabs. Most ground-floor jobs need it.
- Acoustic rubber or cork: denser and heavier, for flats where the body corporate sets a noise limit.
- Fibre or felt boards: sometimes used under glue-down or underfloor heating setups, if the maker allows it.
Thickness, slab condition and moisture
Most underlays are 2 to 5 mm thick. Thicker is not always better: too soft and the click joints flex and fail. Follow the board maker's guidance, and ask the fitter to check the slab with a straight edge. Humps and dips above a few millimetres over two metres need grinding or levelling compound first, as underlay cannot fix them.
A new screed holds water for weeks. Moisture readings come first, then the membrane. Taped overlaps, and a short turn-up at the walls hidden by skirting, keep rising damp out of the boards.
Noise rules in flats and townhouses
Many sectional title schemes require acoustic underlay under any hard floor on an upper level. Ask the managing agent for the rule in writing before you buy. A good acoustic layer softens footfall and reduces the hollow sound inside the room. It is also worth reading about laminate flooring itself, and about laminate flooring installation, where underlay is usually part of the fitting price.
Comparing quotes for underlay
Underlay is sold by the roll or per square metre, so give your floor area plus the usual 10 percent for cuts. Tell suppliers the subfloor, the storey, the flooring type and any noise rule. Ask what the roll covers, the thickness, whether a membrane is built in, and what tape is included. If you want a fitter, check that the quote lists underlay by type, not just "underlay included".
What to include in your request
- The floor area in square metres, plus 10 percent
- Concrete slab, screed, tiles or timber below
- Ground floor or upper storey in a flat
- Any body corporate noise rule
- Supply only, or laid with the floor
Flooring Underlay for different clients
- Homeowners: foam with a membrane under click floors on ground slabs, or basic foam on timber
- Flats and townhouses: acoustic rubber or cork that meets the body corporate's rules on impact noise
- Builders, developers and renovators: membrane underlay laid across whole houses once moisture readings on the screed pass
- Landlords and letting agents: an affordable foam layer that keeps rental click floors quiet and flat
- Offices, practices and showrooms: dense acoustic underlay that dampens footfall in meeting rooms and open-plan areas
- Guesthouses, lodges and restaurants: thicker acoustic underlay under guest room floors to keep noise from neighbouring rooms
- Shops, salons and cafés: firm, thin underlay that holds heavy displays and trolleys without flexing the joints
- Schools, halls, gyms and studios: resilient underlay under floating floors in studios and classrooms to soften impact
Frequently asked questions
Do I need underlay for laminate flooring?
Which underlay is best for a concrete slab?
What underlay do flats and townhouses need?
Do you supply or lay underlay?
Flooring Underlay by province and city
- Johannesburg
- Pretoria
- Centurion
- Midrand
- Sandton
- Randburg
- Roodepoort
- Krugersdorp
- Randfontein
- Germiston
- Boksburg
- Benoni
- Kempton Park
- Alberton
- Vanderbijlpark
- Vereeniging
- Durban
- Pinetown
- Pietermaritzburg
- Richards Bay
- Newcastle
- Ladysmith
- Gqeberha (Port Elizabeth)
- East London
- Kariega (Uitenhage)
- Mthatha
- Cape Town
- Bellville
- Paarl
- Stellenbosch
- George
- Worcester
- eMalahleni (Witbank)
- Middelburg
- Secunda
- Mbombela (Nelspruit)
- Rustenburg
- Brits
- Klerksdorp
- Potchefstroom
- Mahikeng
- Polokwane
- Tzaneen
- Kimberley
- Upington
- Bloemfontein
- Welkom
- Sasolburg