What Is Ipe Decking?

Ipe is a dense tropical hardwood widely regarded as one of the most durable decking timbers available. Its deep brown tones, tight grain structure and exceptional hardness have made it a long-standing choice for high-end residential and commercial decking projects. One of Ipe’s biggest advantages is its longevity. When properly installed, Ipe decking can often last 25 years or more in exterior applications. Southgate Timber stocks a range of Ipe decking profiles, including:

• 21 x 145mm hidden fix decking
• 21 x 145mm standard fit decking
• 19 x 90mm hidden fix decking
• 19 x 90mm standard fit decking

Ipe is commonly installed using hidden fixing systems such as DeckWise Extreme hidden fix clips for a cleaner, more contemporary finish.

What Is Thermory Spruce Decking?

Thermory Spruce decking is a thermally modified softwood designed for improved durability and dimensional stability without the use of chemicals. The thermal modification process changes the structure of the timber using heat and steam, helping reduce moisture absorption and improving stability in exterior environments.

Thermory’s Thermo-Spruce decking has become increasingly popular for contemporary outdoor spaces thanks to its natural Scandinavian character, beautiful visible knots and wide-board modern profile. The lightly brushed surface texture also provides additional grip and a more comfortable barefoot feel. Compared to traditional hardwood decking, Thermory Spruce often creates a lighter, more contemporary architectural aesthetic.

Southgate Timber stocks Thermory Spruce decking in a contemporary wide-board profile, the 26 x 185mm Thermory Benchmark Thermo Spruce D4 SG2 hidden fix decking board, designed for modern architectural outdoor spaces. The profile is installed using the dedicated Thermory PC Decking Clip hidden fixing system, helping create a clean screw-free finish while allowing consistent board spacing and improved installation accuracy.

Appearance

One of the biggest differences between Ipe and Thermory Spruce decking is appearance.

Ipe has rich dark brown tones with fine grain detail and a more traditional luxury hardwood appearance. Over time, if left untreated, it gradually weathers to a silver-grey finish. Many homeowners choose Ipe for its premium natural hardwood character and darker tones. It creates a luxury outdoor space feel with a traditional high-end decking design.

Thermory Spruce offers a cleaner, more contemporary appearance with natural Scandinavian character and beautiful visible knots. Its lighter tones, wider board profiles and brushed surface texture suit modern architecture particularly well while also providing a comfortable barefoot feel. The lighter aesthetic works especially well in contemporary gardens and minimalist outdoor living spaces. Like Ipe, Thermory Spruce can also naturally weather to a silver-grey finish over time if left untreated.

Durability and Lifespan

Both Ipe and Thermory Spruce are designed for long-term exterior use, although they achieve durability in different ways.

Ipe achieves its durability naturally through its extremely dense hardwood structure. It is highly resistant to wear, impact and exterior exposure, making it one of the longest-lasting decking timbers available. When properly installed and maintained, Ipe decking can often last 25 years or more.

Thermory Spruce achieves durability through thermal modification rather than natural density. The heat treatment process improves resistance to moisture and biological decay while also increasing dimensional stability. Thermory states that Benchmark Thermo-Spruce decking achieves Durability Class 1 performance in exterior applications. When correctly installed with suitable ventilation and drainage, Thermory Spruce decking can also provide a very long exterior lifespan.

Stability and Movement

Timber movement is one of the most important considerations in decking design.

Although Ipe is extremely dense and durable, all timber naturally expands and contracts depending on moisture and environmental conditions. Correct spacing and installation are therefore extremely important. Southgate Timber stocks hidden fixing systems such as DeckWise Extreme clips, available with both 2.4mm and 4mm spacing options to help accommodate movement while creating a clean hidden fix appearance.

One of Thermory Spruce’s biggest advantages is its dimensional stability. The thermal modification process helps reduce moisture absorption, swelling and shrinking compared to many standard softwoods. This improved stability is one of the reasons thermally modified decking has become increasingly popular in modern architectural projects. Thermory Spruce decking is installed using the dedicated Thermory PC hidden fixing system for a clean, screw-free finish.

Maintenance

Both Ipe and Thermory Spruce decking require regular cleaning to remove dirt, algae and organic build-up. This applies whether the decking is left to weather naturally or treated to preserve its original colour.

If timber decking has already greyed or become heavily weathered, products such as Owatrol Prepdeck and Owatrol Net-Trol can be used as part of the restoration process. Prepdeck helps strip the surface back, while Net-Trol is used afterwards to neutralise and help restore the timber’s natural tone. The Osmo Decking Cleaning Brush can also be useful when applying cleaning and restoration products.

Oiling is optional and is mainly about maintaining colour rather than improving the structural lifespan of the decking. For both Spruce and Ipe, popular choices include Owatrol Textrol Clear, Owatrol Textrol HES Clear and Owatrol Aquadecks Honey, depending on the finish required. If left untreated, both Ipe and Thermory Spruce will gradually weather to a silver-grey finish over time. This is normal for exterior timber and does not mean the decking has failed.

Sustainability

Both Ipe and Thermory Spruce offer sustainability benefits, although through different approaches.

Ipe is a renewable natural hardwood and FSC-certified options are available from responsibly managed forests.

Thermory Spruce decking is PEFC-certified and uses a chemical-free thermal modification process that improves durability and stability using only heat and steam rather than chemical treatment.

For many projects, both materials can provide a more natural alternative to synthetic decking products while still offering long-term exterior performance.

Cost

One of the biggest differences between Thermory Spruce and Ipe decking is cost positioning.

Ipe is generally considered one of the most premium hardwood decking materials available due to its extreme density, durability and luxury appearance.

While Thermory Spruce decking still sits within the premium decking category, it can offer a more cost-effective route into contemporary architectural decking designs, particularly when using the wider 26 x 185mm board profiles which can create faster visual coverage across larger areas.

The overall project cost will also depend on factors such as:

• hidden fixing systems
• subframe materials
• board widths
• installation method
• wastage allowances
• treatment products

Which Decking Is Best for Your Project?

Choosing between Ipe and Thermory Spruce often comes down to the style and priorities of the project. Both are premium decking materials capable of creating beautiful long-lasting outdoor spaces when correctly installed and maintained.

FAQs

Is Thermory Spruce decking real wood?

Yes. Thermory Spruce decking is real timber that has been thermally modified using heat and steam to improve durability and stability.

Does Ipe decking last longer than Thermory Spruce?

Ipe is widely regarded as one of the longest-lasting decking hardwoods available and can often last 25 years or more. Thermory Spruce also offers excellent exterior durability through thermal modification.

Does Thermory Spruce decking need oiling?

Not necessarily. Like many exterior timbers, it can be left untreated to naturally weather over time or oiled to help preserve the original colour.

Which decking is more stable?

Thermory Spruce is specifically engineered for improved dimensional stability through thermal modification, helping reduce moisture-related movement.

Which decking types use hidden fix systems?

Both Ipe and Thermory Spruce decking are commonly installed using hidden fixing systems for a cleaner, more contemporary appearance.