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.

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.

Treatments

Most people leave their timber to go the traditional silver-grey in the sun. We recommend talking to www.wood-finishes-direct.com if you would like to treat your timber. If you do decide to treat your timber, it needs to be treated all the way round including the ends to prevent moisture getting in at all.

Fitting Guidance

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

Breathable Membrane

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.

Fixing

** 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 or nail head when you fit the board to the batten. Look to leave a 3mm gap between the boards, rather than butting them up tight like flooring, 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.

All our claddings are provided untreated. Fresh sawn timber claddings are best left untreated and to go silver grey. There are a wide range of optional treatments available for different species of timber and we recommend talking to the excellent team at www.wood-finishes-direct.com, who know the most up-to-date information on all the newest treatment products.