Heat Mat 2.88m 7mm Combymat Overlay Boards - CBM-OVE-0280

Each pack of boards covers 2.88m2 and for rooms below 10m2 we recommend supplying boards to cover at least 15% more than room area to allow for off-cuts. For rooms above 10m2 we recommend ordering boards to cover 10% more than the room area, but for particularly complicated shaped rooms we recommend increasing these allowances by 5%.

General supply and storage notes

The boards are supplied in simple to transport packs (1.2m x 0.6m x 2.8cm) which can easily fit into the back of a normal hatchback car. The weight of the packs is roughly 17kg. The packs must be kept dry and should be stored in a moisture free environment with low humidity; the packs must never be stored outside. Pallet deliveries are available for larger orders.

Installation process

Before installing the boards they should have been acclimatised in the room where they are to be fitted for at least 48 hours, at a temperature of at least 18oC. When cutting the boards we recommend the use of a retractable concave bladed knife or similar to avoid creating sawdust, which could prevent the adhesive from correctly bonding. The boards are laid in a staggered pattern with the 3mm boards being laid first, and the 4mm boards on top and an expansion gap of 8-10mm should be left around the perimeter of the room. Any irregularities in the final surface can be easily sanded with 120-grain fine sand paper. Full fitting instructions are supplied with the Combymat System and the Overlay Boards.

Carpet installations

For fixing carpet onto the Overlay Boards it is recommended to use a tackifier adhesive or the double stick method of carpet installation. If using the stretch method of installation the gripper must be installed before the electrical heating system. In order for the gripper to function correctly, the top surface of the gripper should be level with the top surface of the Overlay Boards or underlay. The Tog rating of the carpet and underlay together must be no more than 2.5Tog.

Resilient floor installations

If the resilient floor covering is going to be glued onto the Overlay Boards the boards must be fitted between 24 and 48 hours before the floor covering is laid. This ensures the boards have settled, but should prevent them absorbing too much moisture from the air. When installing the resilient floor covering it should not project beyond the edges of the boards.

Floor sensor positioning

Special attention should be made to the location of the floor sensor and it should be installed as close to the floor surface as possible and be located in an area directly above a heating element in order to achieve accurate control. A wide groove should be made in the top layer of the Overlay Board to take the tip of the sensor and allow the sensor cable to run to the edge of the room without causing a raised area for the final floor covering. The groove and sensor should be entirely covered with flexible filler to ensure an accurate temperature reading and a smooth and level finish to the Overlay Boards.

Key Features

• Enables carpet, vinyl, linoleum and bonded board floors to be laid onto underfloor heating without any wet trade
• Dry and dust free installation
• Creates a very stable, floating sub-floor
• Precision cut boards for quick and trouble free installation
• Very simple to install, the only tools required are a knife, sandpaper and a tape measure
• Saves significant time on installation compared to using mats and a levelling compound
• Heating system and overlay boards can be installed in a single day
• Supplied in 2.88m2 packs
• Boards increase build height by only 7mm, roughly half the thickness of a levelling compound
• Boards are pre-coated with a contact adhesive for speedy installation
• Boards are not suitable for use in wet areas such as bathrooms or wetrooms
• Boards must be acclimatised in the room where they will be installed for at least 48 hours prior to installation