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The Heat-Pak® Dual Overlay System is a highly stable overlay system designed for all types of floor heating. It offers several key features that ensure optimal performance and durability.
Optimal Subfloor Solution: Heat-Pak is specifically designed as a free-floating subfloor system for installation over various floor heating systems. It provides a smooth and stable base, ensuring the long-term durability of floor coverings.
Seamless Surface: The twin layers of Heat-Pak panels are configured with an overlap joint, resulting in a seamless surface. This eliminates the visibility of lines or patterns that may show through shiny floor finishes.
Wide Range of Floor Coverings: Heat-Pak is compatible with different floor coverings such as carpet, linoleum, vinyl, and cork, offering versatility in design choices.
Easy and Quick Installation: Heat-Pak is easy to install and significantly faster and more convenient than traditional smoothing compounds. It is a dry process that minimizes mess and requires no setting time, allowing for immediate flooring installation.
Enhanced Heating System Installation: Heat-Pak simplifies the installation of electric cable, mat, foil, or film heating systems, providing a more convenient alternative to the wet screed method. It ensures the heating elements remain securely in place, keeping the entire system flat and protected.
Efficient Heat Transfer: The Heat-Pak system has an incredibly low thermal resistance (Rm value of only 0.047), allowing heat energy to pass quickly and efficiently to the surface. This results in a fast warm-up time and maximum comfort.
Incorporation of Insulation: Heat-Pak allows for the inclusion of suitable insulation layers below electric systems, maximizing energy efficiency and overall performance.
Premium Quality: Heat-Pak is constructed with high-quality MDF featuring 3mm baseboards and 4mm topboards. Each board is coated with a special interactive contact adhesive, ensuring a strong and permanent full-surface bond. Strict quality controls during production guarantee excellent results and trouble-free installation.
Elevate your floor heating system with the Heat-Pak® Dual Overlay System. Its stability, ease of installation, and compatibility with various floor coverings make it the ideal choice for creating a comfortable and visually appealing space.
Please note: Heat-Pak Dual Overlay must NOT be used in bathrooms, wet rooms, en-suites, or any other wet areas as they will expand upon contact with moisture. For carpet or vinyl installations in these areas, it is necessary to use an underfloor heating mat with self-levelling compound.
1200mm x 600mm
Top Board Thickness
Base Board Thickness
MDF, fitted with an interactive adhesive
Bending Strength (kg/cm²)
Thermal Rm value [m ² ·K ·W » ¹]
Fire Class, DIN4102
Create the first row of baseboards by splitting boards in half lengthways and turning the cut edges toward the wall.
Shorten the first piece to 3/4 of its length, placing both cut edges against the walls in the corner. Lay out the other pieces end to end in a line along the wall, adhesive side up, leaving the protective film in place.
Ensure an expansion gap of 8-10mm around the perimeter and around pipes and fixed objects, including the final floor finish.
Lay out the second row of baseboards in the same direction as the first row.
Cut a board to 1/4 of its length and place this piece, with the cut end against the wall, next to the first row.
Place a full-sized baseboard end to end with the previous piece and alongside the first row. The large off-cut will be used to start the third row of baseboards.
Do not remove the protective film at this stage and keep the job clean and free from dust.
Lay the top boards in the same direction as the baseboards, but with the adhesive side facing down. Position the first board of this row into the corner, overlapping both the first and second rows of baseboards.
If the board fits neatly into the corner, no trimming is required. In that case, lift it out and peel back the plastic film from the baseboards it will cover.
Avoid removing more film than necessary to accommodate the top board on the adhesive. Carefully reposition and adjust the top board for alignment, while checking the baseboards for any gaps and adjusting if needed. Finally, fix the top board in place by tapping it down with a rubber mallet.
To ensure tight joints between the top boards, start the second row with a half-length piece, followed by a full board, and push all the edges tightly together before tapping down.
Continue adding further boards, alternating between the first two rows to maintain straight lines and prevent gaps from developing.
If gluing the final floor finish to the Warmup Dual Overlay, ensure it is done no later than 48 hours after installation to account for possible air humidity influences.
Each room should be fitted separately, leaving an expansion gap of at least 8-10mm (16mm in door openings) when continuing Warmup Dual Overlay into adjoining areas.
If gluing the floor covering onto the total surface, it should not exceed the edges of the Warmup Dual Overlay boards.
This installation method provides a stable surface for the floor finish to rest on, preventing joints from showing through the final floor finish.
With the Warmup Dual Overlay boards installed, you can either glue the final floor finish to the boards as a top layer or lay it freely on top of them. Before installing the final floor finish, test the Warmup foil heater(s) and floor sensor to ensure no damage occurred during installation.
This installation method provides a stable surface for the floor finish to rest on, preventing joints from showing through the final floor finish. With the Warmup Dual Overlay boards installed, you can either glue the final floor finish to the boards as a top layer or lay it freely on top of them. Before installing the final floor finish, test the Warmup foil heater(s) and floor sensor to ensure no damage occurred during installation.
At Underfloor Heating Direct, we strive to make every step of your order as easy and convenient as possible, from finding the right underfloor heating setup to best suit you to taking delivery of your system the very next day.
We're proud to offer a range of delivery options to suit you, including free delivery on all orders over £19.99 or next working day delivery for a fixed price of £4.99.
2-3 working days delivery, order over £19.99 - FREE (£4.99 if under £19.99)
Next working day - £4.99 (Order before 4pm Monday - Friday)
Next working day before 10.30am - £14.99 (Order before 4pm Monday - Friday)
Saturday delivery - £29.99 (Order before 4pm Friday)
30 days returns policy
At Underfloor Heating Direct, our customers have 30 days to upgrade, replace or refund their orders.
At Underfloor Heating Direct, we want to ensure you are happy with every purchase you make. If you have any issues with your chosen product, whether damaged, faulty or simply an unwanted item, you can simply return what you bought for a refund.
We take great care in the delivery of all of our products, however, in the event of your delivery arriving damaged or if you notice a manufacturing fault of any kind within 48 hours of delivery, you're within your rights to a replacement.
Within 14 days of purchasing from us, you are eligible to upgrade if you deem you want something a little better. Simply send it back to us brand new and we'll happily assist you with an upgrade to your order.
At Underfloor Heating Direct, we are committed to providing our customers with high-quality products and outstanding customer service. That's why we offer a comprehensive warranty on all of our underfloor heating products, with a lifetime warranty for our signature kits.
Our warranties are designed to give you peace of mind and ensure that your underfloor heating system operates reliably for years to come.