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Remove and smooth

When laying Karndean over existing flooring, properly prepare it by removing all waxes or sealers. Any patching/leveling or embossing must be brought to a flatness of 5mm in 3 m. 

If the existing floors have been removed, no trace of the previous adhesive residue should remain. To ensure a smooth finish, remove all obvious bumps in the subfloor before applying a smoothing compound or screeding.
Bathroom with concrete subfloor exposed

Check the moisture level

LVT products must only be installed on subfloors with moisture levels below 95% relative humidity (RH) per ASTM F2170 or 8lbs Calcium Chloride per ASTM F1869.

If your reading is above 95% RH or 8lbs Calcium Chloride, regardless of whether the floor is old or new, it’s imperative to install a moisture mitigation system such as our Kovara MBX.

Wood subfloors

Karndean does not endorse/approve any plywood product and takes no responsibility for the performance of any plywood selected.

We recommend the use of a minimum 6 mm (¼”) Underlayment grade plywood that meets the requirements of the American Plywood Association (APA) or panels manufactured to be used as underlayment for resilient floors, as acceptable for use with Karndean products.

It is the responsibility of the installer to verify this compliance through either independent certification or other means. It’s important to remember to follow the underlayment manufacturer’s installation instructions. All fasteners and panel joints must be filled with a cementitious patch and sanded smooth.

Concrete subfloors

If you’re installing Karndean on either a new or old concrete subfloor, as mentioned, it’s essential to conduct a moisture test to ensure the levels are no higher than 95%RH per ASTM F2170 or 8lbs Calcium Chloride per ASTM F1869. If moisture levels are too high, then be sure to install a moisture mitigation system such as our Kovara MBX.
Installer spreading a generic floor leveler

Get screeding

Choosing the right smoothing compound is very much dependent on the type of project, its size and timescale. If prepared and installed correctly, this thin cementitious top layer will ensure that your floor will perform as it should. As such, it's important to consider ambient conditions (ventilation, humidity etc.), installation specifications and curing times.

For further information on subfloor preparation, download our installation guidelines.

Download our installation guidelines

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Stylish designs

Beautifully realistic wood and stone looks in a range of trend-forward colors.

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Commercial performance

Durable LVT with wear layers up to 30 mil and warranties up to 20 years.

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