Maincor Overboard has been designed for projects including extensions, kitchen refurbishments, or upgrading domestic heating systems.
Overboard dry screed panels are used as carriers for pipes in underfloor heating systems. The physical properties of the panels allow heat to spread effectively, which means that installation of heat emission plates is not required.
Panels are available in two configurations, as straights and as end returns. The majority of the heated floor area will usually be covered by the straight panels which are 1.2 x 0.6m and 18mm high. The end returns are used where feed pipes are laid. These are 0.6 x 0.6m (exactly half the size of the straight runs), minimising cutting.
STEP-BY-STEP*
1. Before you start to install the Overboard system, the working area should be prepared. If you take time to plan your installation prior to laying, it will minimise the need to cut panels.
The area must be weather tight. Ensure that the panels, manifolds and electrical components, are sufficiently protected.
The floor should be solid, level, clean and free of debris. A levelling compound can be used to prepare the floor where it is uneven. Screw down any uneven floorboards or replace as required. The sub-floor should comply with the requirements of the Building Regulations Approved Document L.
2. The Overboard panels should be picked up centrally to avoid breaking the corners. Care should be taken and consideration given to the weight of the panels when lifting.
3. Where panels need to be cut, a handsaw, circular saw or jigsaw should be used to ensure they fit the contours of the wall. A suitable dust extraction system should be fitted when power tools are used. Alternatively, the panels can be scored and snapped with a sharp knife and straight edge.
4. Install Maincor edge insulation around the perimeter of the room if needed. The panels must be laid onto a solid, firm sub-floor. Overboard panels should be installed continuously (there’s no need to lay in brick formation), ensuring the pipe channels are lined-up to take the pipe.
5. Prior to laying the pipe, the runs should be determined and effort made to minimise the connecting lengths from the manifold to the pipe channels. The runs should be marked on the panels prior to routing and the pipes should not cross each other within the floor.
6. The panels should be fixed directly to the floor using the Mainadhesive or Overboard screws provided. Generally, screws will be used for fixing to timber sub-floors and adhesive or screws and rawl plugs for concrete floors. If using screws, pilot holes and countersinking is not necessary and the screw will hold better if screwed directly into the panels. Fix around the perimeter of the panels at 200mm centres (not inside the channels).
If using Mainadhesive, it will expand and fully set in approximately four hours – care should be taken during this time to avoid excessive traffic. It is recommended that dots of adhesive are applied at 200mm centres around the perimeter and within the field of the board. After the adhesive has fully set, any excess can be scraped off using a filling knife.
7. Once the panels are laid, the Mainadhesive has set and the feed channels have been routed into the panels (if required), the pipe is ready to be laid. To avoid an excessive pressure drop and maintain the maximum system output, each coil of pipe should not exceed 80m in length. The pipe should be held loosely and walked into the panels.
Take care to ensure the pipe is not kinked, but if this does happen, reform the pipe and create a more gradual bend. The pipe fits very snugly into the pre routed channels and when inserting, there are three fixing points in each channel.
8. Once pressure testing and commissioning of the system are complete, install a separating layer. This will depend on the type of final floor finish and further advice on this can be found in the Overboard brochure on the Maincor website. The joints should be staggered relative to the panels below and fixed down into the Overboard panels with suitable screws.
9. Maincor’s Unitop4 board is a heat distributing 4mm thick, decoupling/stress relieving layer which also reduces impact noise and is suitable for traffic loads of up to 5kN/m².
The compressed cellulose board should be laid upon a bed of MS Adhesive. There is a 25% increase in heat output when using Unitop4 compared with ply.
*NOTE: The above is just a guide, when installing the Maincor Overboard System please always refer to the manufacturer’s full instructions.
