1. It is thermally modified

Before being made into cladding, the spruce is thermally modified using heat and steam at temperatures of around 200°C, without the addition of chemical preservatives. The process changes the properties of the timber, reducing its ability to absorb moisture and improving its dimensional stability. This is particularly useful with black cladding, as darker surfaces absorb more heat from sunlight. Compared with untreated softwood, thermally modified spruce is considerably more stable, helping to reduce the movement associated with changes in temperature and moisture. 

2. The black finish is factory applied

The boards are supplied pre-painted with Thermory Vivid Black, a deep, opaque black finish. Because the coating is applied in controlled factory conditions, you get a consistent finish across the boards without having to paint them before installation. The opaque black finish creates a consistent, modern look across the cladding, making it particularly well suited to contemporary garden rooms, extensions and new builds. It also means no priming or multiple coats on site, helping to save time during fitting. For cut ends or any small areas that need touching up during installation, matching Thermory Vivid Black touch-up paint is also available.

3. The coating is designed for a long service life

According to Thermory, the Vivid coating has an expected service life of around 7 – 10 years in areas exposed to high levels of weathering, with potentially longer intervals in more sheltered locations. Importantly, the black coating isn’t what gives the timber its improved stability and durability. Those properties come from the thermal modification process itself. So, while the coating will eventually need maintenance to retain its black appearance, the timber beneath has already been modified for improved exterior performance.

4. It offers a cost-effective route to black timber cladding

Thermo Spruce offers a cost-effective way to achieve a high-quality timber-clad finish, particularly when compared with premium species such as Western Red Cedar. At around half the price of cedar, it gives you the benefits of thermally modified timber, including improved stability and durability, while keeping the overall material cost more accessible. There are savings during installation too. Because the Vivid Black finish is factory applied, there’s no need for the same level of on-site painting, preparation and drying time you would have with unfinished timber. For projects where you want a modern black timber finish without moving into the cost of cedar, Black Thermo Spruce is a practical alternative.

5. It is made for exterior use

One of the main reasons for choosing Thermo Spruce rather than simply painting standard spruce black is what happens to the timber during thermal modification. Along with its class 1 durability rating, the heat treatment reduces moisture absorption and improves dimensional stability and biological durability without relying on chemical preservatives. That combination makes thermally modified spruce particularly well suited to exterior cladding applications, while retaining the natural appearance and relatively lightweight properties of spruce.

Black Thermo Spruce profiles

There are several profiles within the range, giving you options for the main cladding area as well as details such as corners, reveals and finishing pieces.

• Channel Groove – 19 × 141mm: A clean, contemporary shadow-line finish and the main facing board for many projects.
• Featheredge – 21 × 185mm: A more traditional overlapping, barn-style appearance with deeper shadow lines.
• PAR + Rd – 20 × 140mm: Useful around door and window reveals and can also be used for slatted fencing.
• Corner Profile – 42 × 42mm: Designed for neatly finishing external 90° corners.

Don’t forget the fixings

For a black cladding installation, the fixing details matter too. Spax stainless steel BLAX façade screws have black heads designed to blend into the finished boards rather than standing out against the dark surface. A perforated closure can also be fitted at the top and bottom of the cladding to maintain ventilation behind the boards while helping to prevent insects and vermin entering the cavity. 

Shop Black Cladding

You can shop the entire collection online here or for more information on choosing profiles, ventilation and installation, take a look at our complete Black Cladding Buying Guide. Want to see Black Thermo Spruce Cladding up close? Watch our quick video here as Christian runs through 5 key facts in under 30 seconds.

FAQ's

What is Black Thermo Spruce Cladding?

Black Thermo Spruce Cladding is spruce that has been thermally modified using heat and steam before being given a factory-applied black finish. The thermal modification improves the timber’s stability and durability, while the factory coating provides the finished black appearance.

How long does the black coating last?

Thermory states an expected coating service life of approximately 7 – 10 years in high-weathering areas, with longer intervals possible in more sheltered locations. Maintenance requirements will vary depending on the exposure and conditions of the installation.

Do I need to paint it before fitting?

No. The boards arrive with their Vivid Black finish already applied. Matching touch-up paint can be used on cut ends and any small areas that need attention during installation.

What screws should I use?

We recommend stainless steel fixings suitable for exterior cladding. Spax BLAX façade screws are a good option for this range because their black heads blend into the finished boards.