ThermoDeck® Anti-Slip Decking
ThermoDeck® is GripDeck’s thermally modified timber decking, enhanced with factory-applied anti-slip inserts for a stable, attractive and chemical-free slip-resistant decking solution.
ThermoDeck® Thermally Modified Anti-Slip Decking
ThermoDeck® is GripDeck’s thermally modified timber decking product. It is designed for projects where customers want the natural appearance of timber, improved dimensional stability and the benefit of GripDeck® factory-applied anti-slip inserts for better decking grip.
ThermoDeck® is also known as thermally modified timber decking or modified timber decking. The timber is modified using heat and steam rather than chemical preservative treatment, changing the structure of the wood to improve stability and durability.
What Is Thermally Modified Timber?
Thermally modified timber is timber that has been heated to high temperatures in a controlled process using heat and steam. This changes the timber at a cellular level, reducing its ability to absorb moisture and improving stability for external decking boards.
The process is chemical free. ThermoDeck® is not pressure treated with preservative in the way standard softwood decking is. Instead, the timber is modified using temperature and steam to improve performance for external use, making it a strong option for premium timber decking projects.
Heat Modified
The timber is heated in a controlled process to permanently alter its characteristics.
Chemical Free
The modification process uses heat and steam rather than chemical preservative treatment.
Improved Stability
Thermally modified timber absorbs less moisture, helping reduce movement, swelling and shrinkage.
How the Thermal Modification Process Changes the Timber
| Change | What It Means for Decking |
|---|---|
| Reduced moisture absorption | The timber becomes less reactive to moisture changes, improving dimensional stability. |
| Improved stability | Boards are less likely to move, swell or shrink compared with untreated timber. |
| Darker colour tone | The heat process gives the timber a warmer brown appearance that will weather naturally outside. |
| Improved decay resistance | The modification process helps make the timber more durable for external applications. |
| No preservative treatment | The product is modified by heat and steam rather than chemical treatment. |
Why Choose ThermoDeck®?
Stable Timber Decking
ThermoDeck® offers improved stability compared with standard untreated timber, making it suitable for high-quality garden decking, terraces, balconies and commercial decking projects.
Factory-Applied Anti-Slip Inserts
GripDeck® anti-slip inserts are machined and bonded into the board surface under controlled factory conditions to create a consistent slip-resistant decking surface.
Chemical Free Modification
The timber is thermally modified using heat and steam rather than preservative treatment, producing a chemical-free modified timber decking board.
Attractive Warm Colour
ThermoDeck® has a rich, warm appearance that suits modern gardens, terraces, balconies and commercial outdoor spaces.
Clip Fixing Available
ThermoDeck® can be supplied with curved or slotted edges to work with suitable hidden clip fixing systems.
LOW Slip Risk
GripDeck® anti-slip products have achieved LOW slip risk potential in both wet and dry conditions, helping ThermoDeck® provide a safer decking surface outdoors.
View Test ResultsClip Fixing System Available
ThermoDeck® can be supplied with a curved or slotted edge profile suitable for use with a hidden clip fixing system. This can create a cleaner finished appearance because fixings are less visible on the modified timber decking surface.
Clip fixing can be particularly useful for premium garden decks, terraces, balconies and design-led projects where appearance is important. Suitability will depend on the chosen ThermoDeck® board profile, substructure, fixing system and project requirements.
Slotted Edge Profile
ThermoDeck® can be profiled for compatible hidden clip fixing systems.
Discuss Profile
Clip Fixing Detail
A discreet fixing option for selected ThermoDeck® and thermally modified timber board profiles.
Ask for AdviceCleaner Finish
Hidden clip fixing can reduce visible screw heads on the decking surface, giving thermally modified decking a cleaner, more refined appearance.
ThermoDeck® Profiles & Insert Layouts
ThermoDeck® can be manufactured with GripDeck® anti-slip inserts to suit the chosen board profile and project requirements. This creates a durable, slip-resistant thermally modified timber decking surface. The most common layout is 2 inserts per board, with 3 inserts available where the main direction of travel follows the board length.
ThermoDeck® Board
Thermally modified timber decking with factory-applied anti-slip inserts.
Request Quote
ThermoDeck® Finish
A warm modified timber appearance for modern garden decking, terraces and premium outdoor projects.
Request Samples2 or 3 Insert Layouts
Two inserts are suitable in around 90% of applications. Three inserts may be preferred for long walkways, bridges and ramps where additional decking grip or enhanced slip resistance may be required.
ThermoDeck® Specification
| Description | ThermoDeck® thermally modified anti-slip timber decking |
| Timber Type | Thermally modified timber |
| Modification Process | Heat and steam modification process; chemical free and not preservative treated |
| Profiles | Smooth, grooved, curved edge or slotted edge profiles available subject to specification |
| Fixing Options | Traditional face fixing or suitable clip fixing system depending on board profile |
| Anti-Slip Inserts | 2 no. per length as standard. 3 or more inserts available on request depending on board width and project requirements. |
| Aggregate | Standard grey bauxite. Colours may be available on request. |
| Testing | GripDeck® anti-slip products have achieved LOW slip risk potential in both wet and dry conditions, helping ThermoDeck® provide a safer decking surface outdoors. |
| Accreditation | TDCA DeckMark Plus |
| Certification | FSC® certified products available on request, subject to availability. |
Is ThermoDeck® Treated Timber?
ThermoDeck® is not pressure treated in the same way as standard treated softwood decking. Instead, the timber is thermally modified using heat and steam. This process changes the structure of the timber and improves its suitability for external decking without adding preservative treatment chemicals.
Where Can ThermoDeck® Be Used?
Garden Decking
Ideal for customers who want premium garden decking with a warm timber appearance and improved stability.
Terraces & Outdoor Living
Suitable for patios, terraces, seating areas, outdoor dining spaces and contemporary garden designs where a stable timber decking board is required.
Commercial Spaces
ThermoDeck® can be used for commercial outdoor areas where appearance, stability and decking grip are important.
Balconies & Raised Decks
Clip fixing options may be useful for balconies and raised decks where a clean, modern finish is required.
Walkways
Factory-applied anti-slip inserts make ThermoDeck® suitable for selected walkway applications requiring a slip-resistant decking surface.
Design-Led Projects
A strong choice for design-led projects where natural timber appearance, modified timber stability and hidden fixing options matter.
ThermoDeck® vs Softwood and Hardwood GripDeck®
| Feature | ThermoDeck® | Softwood GripDeck® | Hardwood GripDeck® |
|---|---|---|---|
| Best for | Stable, premium-looking thermally modified timber decking with modern fixing options | Cost-effective anti-slip decking | Premium and long-life hardwood projects |
| Timber process | Thermally modified using heat and steam | Pressure treated softwood | Natural hardwood species |
| Chemical treatment | Chemical-free thermal modification process | Tanalith treated | Usually naturally durable species |
| Appearance | Warm thermally modified timber colour | Pale green to honey brown, then silver grey | Varies by hardwood species |
| Fixing options | Face fix or clip fixing depending on profile | Usually face fixed | Usually face fixed |
Technical Resources
Anti-Slip Test Results
View wet and dry slip resistance test results for GripDeck® anti-slip decking products.
View Test ResultsDownloads
Download specification sheets, certificates, brochures and technical documents.
View DownloadsTimber Species Guide
Compare softwood, hardwood and thermally modified timber options for decking projects.
View Timber GuideNeed ThermoDeck® Anti-Slip Decking?
Tell us your required board size, profile, quantity, insert layout, fixing preference and delivery postcode and GripDeck® will provide a project-specific ThermoDeck® quotation.
Request a Quote Request SamplesFrequently Asked Questions
What is ThermoDeck®?
ThermoDeck® is GripDeck’s thermally modified timber decking product, available with factory-applied anti-slip inserts for improved slip resistance.
Is ThermoDeck® the same as thermally modified timber?
ThermoDeck® is our branded thermally modified timber decking product. Thermally modified timber is the general name for timber that has been modified using heat and steam.
Is ThermoDeck® chemically treated?
No. ThermoDeck® is thermally modified using heat and steam. It is not pressure treated with preservative chemicals.
Can ThermoDeck® be fitted with hidden clips?
Yes. ThermoDeck® can be supplied with a curved or slotted edge profile suitable for compatible clip fixing systems, depending on specification.
Can ThermoDeck® have anti-slip inserts?
Yes. ThermoDeck® can be supplied with GripDeck® factory-applied anti-slip inserts to create a slip-resistant thermally modified decking surface.
Is ThermoDeck® available online?
Selected standard ThermoDeck® products can be purchased online where available. Bespoke ThermoDeck® board sizes, profiles, clip fixing options and project-specific layouts should normally be quoted.