How to install timber cladding correctly at ground level

Natural timber cladding can look great on a building, but you need to be design and install it correctly to stand the test of time, particularly at ground level. Unfortunately, poor detailing is far too common in modern construction projects. Below, we look at a classic mistake regarding how not to fit your boards near the floor, along with the proper technical clearance guidelines you should follow instead.

Common mistakes when installing cladding near ground level

The first photo, in my opinion, is a bad example of building detailing. Here, the cladding is taken all the way down to ground level and sits in direct contact with the ground.

When timber is installed this low, it can continuously soak up groundwater through moisture capillary action. It also suffers from continuous splashing of rainwater rebounding off the floor up onto the lower sections of the boards. Over time, this poor installation practice leads to:

• Timber rot and structural decay

• Rapid deterioration of surface finishes and stains

• Dark water staining along the base of the wall

• Algal growth and moss accumulation

As it happens, this first photo was taken at a National Trust visitor centre relatively recently. This surprised me, as I thought the National Trust usually had good designers and skilled contractors working on their historic and modern buildings alike.

         

How to install timber cladding at ground level the right way

To avoid premature timber failure, proper ground clearance is essential. Ideally, any exterior timber cladding near the ground should finish at least 200mm above ground level to drastically reduce the risk of splashback and ground moisture absorption.

The second photo comes from an old TRADA [Timber Research and Development Association] cladding design guide – which is unfortunately no longer in publication since TRADA’s demise, a bit of a loss for architectural detailing resources. Following established industry guidance ensures your natural wood cladding can remain dry, well-ventilated, and structurally sound for decades.