Type: Softwood
Source: Scandinavia
OVERVIEW
Thermowood has a high resistance to moisture and decay which makes it a good option for exterior cladding. Thermowood is a straight grained softwood which offers a more consistent finish. Thermowood density is in-between Cedar and Larch and is darker in colour. Thermowood is thermally modified which increases stability and provides resistance against shrinkage, swelling and distortion. Thermowood is heat treated to a temperature of 180 degrees.
Suitability of Profiles
Wide choice of standard profiles.
| Profile | Cladding Joint | Horizontal | Diagonal | Vertical | Thickness |
|---|---|---|---|---|---|
| Tongue & Groove | Closed | Yes | Yes | Yes | 20mm min. |
| Rectangular | Closed | No | No | Yes | 16-25mm+ |
| Feather Edge | Closed | Yes | No | No | 9mm x 16-15mm |
| Shiplap | Closed | Yes | No | Yes | 18mm |
| Parallelogram | Open | Yes | No | No | 16-25mm+ (up to 50mm) |
DURABILITY
| Desired service life (years) | |||
|---|---|---|---|
| Natural durability class | Need for treatment/modification | Occasionally wet | Frequently wet |
| 1 (Very durable) | Suitable without treatment | >60 | 60 |
| 2 (Durable) | Suitable without treatment | 60 | 30 |
| 3 (Moderately durable) | Suitable without treatment except for tall or exposed buildings | 30 | 15 (untreated) |
| 4 (Slightly durable) | Treatment required | 15-30 years treated | 15-30 years treated |
| 5 (Not durable) | Treatment required | 15-30 years treated | 15-30 years treated |
| Common Name | Natural Durability Class BSEN350:2:1994 | Sapwood Treatability | Movement | Strength |
|---|---|---|---|---|
| Thermowood (European) | 2 | Resistant | Small | High |
TREATMENTS & FINISHING
- Doesn’t necessarily need a surface treatment applied to it, however you can choose to add a finish, stain or paint to their timber to enrich its colour, but if it’s left untreated, the wood will naturally change to a silvery grey (similar to that of cedar or larch)
| Cladding Treatment | Notes | For which species? |
|---|---|---|
| Tanalith (Green) | High Pressure Treatment – Green Coloured Finish. Once treated, timber can go in the ground | Soft Wood Only |
| Tanalith (Brown) | High Pressure Treatment – Brown Coloured Finish. Once treated, timber can go in the ground | Soft Wood Only |
| Vac – Vac (Clear – Yellowish) | Low Pressure Treatment – Green Coloured Finish. Can only use above ground | Soft Wood Only |
| Fire Retardant | Pressure Treatment | All Species |
| UV Protection | Vacuum Applied | All Species |
| Full Range of Stains and Colours | All Species | |
| Clear Lacquer | Vacuum Applied | All Species |
SPECIFY
If you have decided that Timber Cladding is going to be one of the materials on your project the next step is to create a specification that will meet the criteria and expectations you, and your client have.
We offer installation guidance, detailing guidance based on TRADA documentation, with a wealth of knowledge and information on how different timbers will perform over the life span of your project.
Considerations that should be made when it comes to weather, along with how elevation and design variations can impact timber cladding.