Knauf Brio WarmFloor

Installation Procedures

Knauf Brio dry screed flooring is designed to be simple and fast to install. Knauf Drywall Technical Services are on hand should you have any questions or unusual situations to deal with.

General

Knauf Brio dry screed flooring must be installed in accordance with Knauf Drywall’s recommendations and needs to be fully supported and installed on a level and flat base. This may require the substrate to be levelled in preparation, for example through the use of a wet screed or a dry bulk leveller with a minimum density of 370Kg/m3. It should be noted that dry bulk levellers are not considered suitable where the floor is to be subjected to dynamic loads.

Perimeter

Once the subfloor has been levelled, fit Knauf Brio Edge Strip to all perimeters. In order to prevent the flanking transmission of impact noise, cut the excess from the Knauf Brio Edge Strip at a minimum of 5mm above the Knauf Brio floor. This isolates the Knauf Brio floating floor from the walls and maintains the fire performance.

Laying Brio

Knauf Brio dry screed boards should be installed with the printed side showing on the upper face.

Over a solid, level subfloor
The first board should be laid in the far left corner of the room (see laying scheme diagram opposite). The edge profile of the boards abutting the walls should be cut with a circular saw or jigsaw to fit the contours of the wall. A suitable dust extraction system should be fitted to the saw.
Brio is installed continuously in a broken bond pattern with a minimum staggered overlap of 200mm (see laying scheme diagram below).

Over dry bulk levellers
Level the dry bulk leveller as per the manufacturers instructions. Install the Brio as above, but start in the opposite corner (see Laying Scheme diagram opposite), taking care not to disturb the uncovered bulk leveller.

Fixing

Knauf Brio boards are glued together then screwed as they are laid.

Apply two parallel beads of Knauf Brio Joint Adhesive to the lower rebate of the board using the special applicator nozzle. Offer up the next board, butting the joints tightly together; standing on the board will press the rebates firmly together creating a level surface.

Mechanically fix the Brio boards together using the correct Knauf Brio Screws along the blue fixing guideline at maximum 300mm centres once the first row is in place. This will ensure the surface remains level as the adhesive expands, creating a solid and stable finish.

Knauf Brio Joint Adhesive will expand and set in approximately 4 hours - care should be taken during this time to avoid excessive traffic. Once the adhesive has fully set any excess can be scraped off using a filling knife.

Door openings

When installing Knauf Brio over insulation in several adjoining rooms you should aim to continue the floor through the door gap. Any joint that occurs in, or just outside of the door gap should be supported with a wooden strip equal to the thickness of the insulation as per the Butt Jointing Brio at Door Openings detail.

Movement joints

Where Knauf Brio is being installed over an underfloor heating system movement control joints should be installed where the wall length exceeds 20m and in doorways where Brio is being run continuously. Movement control joints should also be installed to coincide with any movement joints in the structure.

Floor coverings

Knauf Brio is suitable to receive a wide variety of floor coverings including carpets, vinyl, tiles, wooden and laminate flooring.

Floor coverings should not be installed until 24 hours after the installation of the Knauf Brio dry floor screed.

Thin vinyl coverings
Fill and smooth the Knauf Brio joints with Knauf Uniflott to ensure a seamless finish before applying a primer to the manufacturers recommendations.

Elastic coverings
If an elastic vinyl or linoleum covering is to be installed then the surface of the Brio should be smoothed using a fine calcium sulphate self levelling screed.

Stone and ceramic tiles
Prime the surface of the Knauf Brio as per the tile adhesive manufacturers recommendations. If tiles larger than 330 x 330mm are to be installed please contact Knauf Drywall Technical Services for more information.

Wooden flooring
Adhere timber floor coverings to the Brio following the recommendations of the timber floor manufacturer. Some laminate floor coverings may be unsuitable for use over Knauf Brio when used with an underfloor heating system.

Wet areas
Fully tank the entire surface of the Brio to protect against leaks.

Underfloor Heating Considerations

Knauf Brio 23 should be specified for use over underfloor heating systems. The flow temperature for wet systems should not exceed 55°C.