British Douglas Fir Tongue and Groove Cladding
There are five different default British Douglas Fir Tongue and Groove Profiles that we supply which are:
- IWC1 - 19mm x 145mm overall, with a 135mm face - For horizontal or vertical fitting
- IWC2 - 19mm x 95mm overall, with an 88mm face - For horizontal or vertical fitting
- IWC3 - 19mm x 142mm overall, with a 125mm face - For horizontal or vertical fitting
- IWC4 - 19mm x 145mm overall, with a 125mm face - For horizontal or vertical fitting
- IWC5 - 19mm x 145mm overall, with a 125mm face - For vertical fitting only
Our tongue and groove cladding is the most versatile that we supply in that the majority of the profiles can be fixed horizontally or vertically (only IWC5 must be fitted vertically).
We supply British Douglas Fir as Fresh Sawn Merchantable grade. British Douglas Fir is a great softwood and can be used for almost any external purpose which makes it a great cladding material. The timber colour varies and is usually a pale reddish-orange colour but can be at either end of the scale (pale red or orange) within the same order.
You can treat your cladding to keep its original colour by using a UV protection oil. This will prevent the wood from turning silvery grey for longer by protecting it against the sun. We would recommend applying the treatment before you use your cladding in order to get a complete coating.
The demand British timber is becoming greater and greater which gives us the opportunity to showcase some of the best that we have to offer. It is becoming a lot more common for projects to specify British timbers over their foreign counterparts and we are proud to supply the best that Britain has to offer.
British Douglas Fir Tongue and Groove Cladding is supplied in random lengths which are 3m and longer. If you have any special length requirements please give us a call on 01889 597281 or talk to us on the chat to discuss them. If we can produce your order to the requirements you specify then please enter them in the “Special Instructions” box on the shopping basket page before ordering.
Be sure to read through our treatment information by clicking on "Treatment Guidance" above. It talks about sealing, preserving and protecting the timber from the sun's UV rays. Here are quick links to the products we recommend:
These fitting guidelines are only a rough idea on how to fix your tongue and groove cladding. We do recommend you employ a professional who has experience fitting tongue and groove cladding.
Be sure to read our treatment guidance as treatment needs to be applied prior to fixing your cladding
Consult a fitter to determine if your scenario would require the fitting of a breathable membrane between your wall and the cladding. This membrane stops rain getting to the wall, but allows moisture to escape, helping to prevent internal condensation and mould that can come with it.
Treated Softwood Battens
Treated softwood battens (available from our cladding accessories pages) are most commonly used to fix to the wall (or on top of the breathable membrane) to then fix your cladding to. If you are fixing your cladding horizontally, your battens need to be placed vertically, at around every 600mm (60cm), and vice versa.
** Whether you use nails or screws, it's important that they are stainless steel, or silicone bronze ARS, so that the natural tanins in the timber will not corrode them. Never use iron nails for fixing timber.
To help stop the wood from splitting we recommend pre-drilling the timber and then holding it with the screw head when you fit the board to the batten. Look to leave a 3mm gap between the boards to account for any moisture movement and make sure that the tongue is facing upwards otherwise moisture will start gathering in the groove of the profile.
You can also use nails, preferably ring-shanked for extra grip, and again stainless steel so they don't corrode. For lower-density species like cedar, consider using nails with larger heads so the cladding doesn't pull through.
You can fit IWC 1,2,3 and 4 vertically or horizontally depending on the look you want from your timber. Whilst technically you can fit IWC5 horizontally, water can sit in the square channel, which is not recommended.
With each new row of cladding you add, it's preferred that you stagger the joins between each board so you don't create a visible seam.
As already stated, these are just ideas to get you thinking about installation and you should consult a professional installer before fitting your cladding as every scenario is different.
Treating Timber Cladding
All of our timber cladding is provided untreated.
For best results, cladding should be treated before it is installed to ensure application of the treatment on all sides and ends of the boards.
We recommend Wood Finishes Direct for all of your treatments. We have found them to be well priced and their telephone support and advice is second to none. We highly recommend giving them a call.
The following information is from Wood Finishes Direct in relation to treating timber cladding.
When it comes to treating your timber cladding, there are three areas of protection to consider.
- Sealing against moisture movement - Sealants are used to help prevent moisture entering the wood causing it to expand. Kiln dried timber like European Oak will definitely need to be sealed, and for other timbers it is highly recommended.
- Wood Preserver - Helps to prevent rot and protects the wood from insect infestation and mould.
- UV Protection - The ultraviolet rays of the sun slowly bleach external timbers. UV protection oil helps to keep the natural colour of your timber for longer and prevent it from turning silvery grey so quickly. Some people like their timber to weather and prefer the silvery grey look so it’s completely down to you.
The following links will take you straight to the products on Wood Finishes Direct's website:
Product to Seal and Preserve
To address Sealing and Preserving, they recommend applying one or two coats of "Wood Preserver Basecoat - Barrettine Premier Universal Preserver" before installation to seal against moisture movement and protect it from mould and insects.
Product to Protect from UV Rays
Then to optionally delay weathering, two coats of OSMO UV Protection Oil. There are different colours of OSMO UV Protection Oil available, with names like 'Cedar' and 'Oak', but these colours are to make other timber look like the stated species. We recommend the 420 clear version which interferes the least with the natural colour of your timber.
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Fresh Sawn Merchantable Grade
Fresh Sawn Merchantable Grade British Douglas Fir External Cladding Tongue and Groove Cladding from iWood Timber
Some commonly asked questions
Our timber is imported straight from sawmills on the continent. Our usual lead times are therefore 14 to 17 working days.
What are your delivery costs?
We calculate our delivery costs based on how far away you are from us, to get more information on this please check out our shipping costs page HERE.
How do I receive a delivery?
Our timber deliveries can sometimes be heavy, for this reason you'll either need your own equipment or available person-power to unload your delivery.
How do I place an order for cladding?
You can place your order online by working out your price above and adding your items to your shopping basket. You can then check out and your order will be processed securely and a confirmation email sent. Once your order arrives in our depot, we'll give you a call to arrange delivery.