INTRODUCING THERMALLY MODIFIED WOOD PIONEERS IN THERMOWOOD® PRODUCTS
WHAT IS THERMOWOOD®?
Since 1990 comprehensive research on heat treatment (thermal modification) has led to a commercialized process in Finland. An industrial-scale wood heat treatment process, under the trade name of ThermoWood, has been developed at the Finnish Research Center VTT together with the Finnish industry. Today the process is licensed to only 16 members of the Finnish International ThermoWood Association worldwide.
BENEFITS
- Superior stability and durability.
- Due to complete cell collapse, ThermoWood®’s Equilibrium Moisture Content (EMC) is more than half that of unmodified wood thus significantly reducing its ability to absorb moisture.
- No swings in moisture content equal better stability. A decreased difference in swelling will result in fewer tensions in the wood creating a better wood product.
- This improved stability means ThermoWood® is less likely to cup, warp or twist. Like all wood products, minor seasonal expansion and contraction is to be expected – as such we recommend minimum gapping of 5/32″ between deck boards.
- ThermoWood® outperforms unmodified wood in environments with fluctuating relative humidity.
- The thermal modification process is proven to densify wood, making it up to 33% harder.
- Western Red Cedar has a low Janka hardness rating of only 350, while Western Hemlock has a much higher rating of 500. And, when treated by thermal modification, Western Hemlock’s Janka hardness rating rises even higher, to a maximum of 665 – almost twice the hardness of cedar – and just above Douglas Fir, which is rated at 660.
- American White Ash, when treated, is equal with Wenge at 1930 on the Janka Hardness Scale.
- Thermal modification significantly reduces many of the nutrients and properties that attract insects and support the growth of rot and fungus.
- As extractives and resins are removed in the process, the durability of painted surfaces is greatly improved. With no extractives in the wood to bleed through the finishes, you have less flaking and peeling. This reduces the maintenance needs of the wood.
- ThermoWood® is smooth, splinter free, lighter in weight and machines beautifully.
- Thermal conductivity is up to 25% lower than unmodified wood.
- This provides improved insulation performance as the wood does not heat up.
- No hot feet on summer decks!
PRODUCT LIST
DECKING
THERMOWOOD® ASH DECKING S4S E4E
1×4 (0.75″x3.5″) R/L 6′-13′
5/4×4 (1.0″x3.5″) R/L 6′-13′
5/4×5 (1.0″x4.5″) R/L 6′-13′
5/4×6 (1.0″x5.5″) R/L 6′-13′
8/4 x3 (1.5″x2.5″) R/L 6′-13′
8/4×4 (1.5″x3.5″) R/L 6′-13′
8/4×5 (1.5″x4.5″) R/L 6′-13′
8/4×6 (1.5″x5.5″) R/L 6′-13′
THERMOWOOD® ASH STAIR TREADS S4S
8/4×12 (1.5″x11.25″) R/L 6-13′
THERMOWOOD® HEMLOCK DECKING S4S E4E
6/4×5 (1.25″x4.5″) R/L 6′-13′
6/4×6 (1.25″x5.5″) R/L 6′-13′
thermowood® DECK TILES
Available in various sizes, made to order.
CUSTOM SIZES/PROFILES AVAILABLE
LUMBER
THERMOWOOD® ASH LUMBER S4S E4E
2×4 (1.5″x3.5″) R/L 6′-13′
2×6 (1.5″x5.5″) R/L 6′-13′
SIDING & SOFFIT
THERMOWOOD® ASH SIDING
1×4 (0.75″x3.5″) R/L 6′-13′
1×5 (0.75″x4.5″) R/L 6′-13′
1×6 (0.75″x5.5″) R/L 6′-13′
1×3 (0.75″x2.5″) R/L 6′-13′
1×4 (0.75″x3.5″) R/L 6′-13′
V-Joint or Fineline Profiles available
THERMOWOOD HEMLOCK SIDING & SOFFIT
1×4 (0.75″x3.5″) R/L 6′-13′
1×5 (0.75″x4.5″) R/L 6′-13′
1×6 (0.75″x5.5″) R/L 6′-13′
1×3 (0.75″x2.5″) R/L 6′-13′
1×4 (0.75″x3.5″) R/L 6′-13′
V-Joint or Fineline Profiles available
Good for the Local & Global Environment
Scottywood’s thermal modification process uses only heat and steam. No chemicals are used in this process, which means nothing nasty leeches into the soil making this product environmentally sustainable. Emission measurements show higher emissions of terpenes, camphene etc. on unmodified wood vs. ThermoWood – more than triple the amount.
Scottywood uses wood species sourced from renewable, sustainable North American forests. Scottywood is more stable and durable than other woods, this extends its’ service life and reduces the lifetime maintenance needs of the wood. By using domestic wood species, in place of tropical hardwoods, Scottywood is helping to keep money in the local economy rather than having to source imported products from around the world.
Unsurpassed Colour & Beauty
- Thermal modification creates a rich, deep colour throughout the wood. The colour and beauty resemble more expensive, exotic tropical hardwood species.
- The rich colour can be easily replicated and precisely controlled with our specialty software.
- Like many tropical hardwoods, Scottywood will naturally age to a striking silver/grey when exposed to direct sunlight.
- Maintain the exotic colour with an oil-based, UV protectant applied every few years or annually for top performance.
STANDARD TOOLS
ThermoWood® works well with standard woodworking tools, but it is important that special attention is given to saw and tool coarseness/fineness to better improve the end result. We recommend that all blades and routers have carbide tips. Saw speed will have an effect on the cut quality; generally, the higher the saw power, the better the cut quality. Use dust masks and protective eyewear for safety.
GLUE ABILITY Many industrial types of glue may be used; PVAc Polyvinyl, PU Polyurethane, EPI Isocyanate and RE Resorcinol.
FASTENING
When face mounting we recommend to pre-drill and countersink then fastened with stainless steel screws.
Stainless steel fasteners must be used as wood is very acidic and will corrode iron which would then
cause mineral stain to occur. Minimum screwing distance from edge: ¾” Minimum screwing distance
from end: 1 ½”. Nailing is not recommended when installing as splitting can occur. We recommend a spacing of 5/32″ between boards to allow for seasonal expansion/contraction and to prevent gaps from closing, which can result in water pooling on the surface.
FASTENING TO SURFACES OTHER THAN WOOD
When fastening directly to surfaces other than wood (aluminum, steel, galvanized steel, etc.) it is
recommended to use a wood skin on top of these metal surfaces to avoid movement due to the amount
of contraction and expansion these metal materials can experience. (Do not fasten ThermoWood® deck or
siding boards directly to metal) and use appropriate fasteners (see above).
AVOID CUPPING
Never fasten ThermoWood® directly to any surface that would eliminate airflow from reaching the back of
the board. Use of wood furring strips to create the necessary spacing is highly recommended. Especially
on boards 8” or wider.
JOIST SPACING
It is recommended that joists be installed no more than 16” on centre, or local municipality code
regulations. Use standard residential deck codes to determine on-centre space for decks and stairs.
COATING
Coatings are not necessary to protect ThermoWood® from decay. However, just like other woods, if left
untreated, it will naturally weather and alter the products original appearance. To help maintain the
original appearance and natural beauty of our ThermoWood, high-quality wood OIL protection products
with UV inhibitors should be applied. If left untreated with no UV protection ThermoWood will grey to a
silvery patina which is often a desired final appearance by our customers. DO NOT use water-based
products – ONLY oil-based.
STAINS AND SCRATCHES
If your deck surface becomes stained or scratched due to barbecue spills, wines, condiments, dog nails,
high heels, etc. most of these will fade and become less noticeable over time. Deeper scratches and
stains can be blended with a light sanding. Sanding will expose the original tone of the boards which will
again gradually silver to match the surrounding area. For surfaces with an oil finish, reapply the oil to
match the surrounding area.
