Heat Mat CBM-OVE-0280 2.88m2 of 7mm Combymat Overlay Boards
Heat Mat's Combymat Overlay Boards allow the Combymat heating system to be installed beneath carpet, vinyl, linoleum and bonded board floors without needing to cover the heating system with a levelling compound. By enabling a dry installation without any wet trade the system saves installation time and costs and also minimises build height; the total build height of the Combymat System with underlay, and the Overlay Boards, is only 13mm.
The Overlay Boards provide a strong and smooth floating sub-floor which accepts carpet and most resilient floor coverings, and floor coverings can be changed if desired while leaving the heating system in place. The use of the boards means a rapid installation is possible when compared to using a levelling compound. Carpets can be fitted the same day as the Overlay Board installation is completed, any other floor surfaces must be fitted between 24-48 hours after laying the boards.
The boards utilise an overlap joint configuration to produce a seamless final finish and prevent lines from ghosting through shiny floor finishes. The very low thermal resistance of the Overlay Boards enables valuable heat energy to pass quickly through to the floor surface for a fast warm up time and improved energy efficiency.
When used with carpeted floors the Overlay Boards provide a resilient protective covering on top of the heating system and also help to spread the heat, lowering the risk of thermal blocks above the heating system.
- Install electric underfloor heating beneath a variety of floor coverings with minimum build height and no wet trade
- Create a stable and very smooth floating sub-floor with easy to cut boards
- Suitable for use with carpet, vinyl, linoleum and bonded board floors
- Precision cut boards are pre-coated with a contact adhesive ensuring a fast and smooth installation
- Pack sizes of 1.2m x 0.6m ensure they are lightweight and easy to transport
- A simple one person job to install
Please note, the Combymat System and Overlay Boards are not suitable for use in wet areas such as bathrooms. The Overlay Boards are sensitive to moisture, so if there is a risk of moisture rising through the sub-floor a damp proof membrane must be installed beneath the Combymat insulation. The boards must always be stored in a dry environment.
Selecting the correct amount of boards
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.
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.
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.
- 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
- Compressive strength: 300kPa
- Overall thickness: 7mm +/- 0.2mm
- Board dimensions: 600mm x 1200mm
- Pack size: 2.88m2
- Pack part number: CMB-OVE-0288
- Compatibility: Only compatible with Heat Mat Combymat System
- Materials: MDF coated with a contact adhesive
- Density: 770 kg/m3
- Bending strength: 40kg/cm2
- Fire Class, EN 13501:2007 E FL
- Thermal resistance Rm value: (m2, K.W) 0.047
- Humidity: % 4 - 10
- Water absorption: after 2 hours <40%
Why Choose Heatmat
With more than 1,400,000m2 of underfloor heating installed, 22 years’ experience of the UK underfloor heating market and a wealth of knowledge on Scandinavian ice and snow melting systems, you can rely on Heat Mat to understand your needs and supply the products to satisfy your requirements.
This is why they are the Professionals’ Choice, the number one supplier of electric underfloor heating and ice and snow melting systems to the UK’s professional installation market.