Timber cladding brings natural warmth, texture and lasting elegance to the outdoors. It helps create an attractive, natural, organic connection with its surroundings, while providing durability, versatility and sustainability.
However, over time, poor installation and lack of maintenance can cause it Wood cladding Faded, and ugly, unwanted streaks appear around the fixings. Here we look at the reasons why timber cladding deteriorates, suggestions for fixing it and expert tips to help protect and maintain it for a long life.
Tom Barnes heads Western Timber, a family-owned company that manufactures oak beams, timber cladding and hardwood flooring.
Causes of Timber Cladding Ruin
There are many reasons why wood cladding deteriorates. Some fittings have flaws, while others nature takes its course. The type of problem is a good indicator of the problem.
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Tom Barnes, Managing Director Western woodshares one of the most common problems: “The most common culprit is the fixings. Galvanized or zinc-plated nails and screws are not made for exterior wood.”
He adds, “Once moisture penetrates the protective coating, corrosion begins. That corrosion reacts with the natural tannins in the wood, causing dark streaks to run down each fixing point.”
Another common cause is lack of maintenance and nature taking its course. “Graying is a completely different matter. If untreated, wood is naturally silver-grey,” says Barnes. He adds, “In polluted areas or at north-facing elevations, the board may turn black instead of gray. It’s not a failure. It’s wood that’s wooding out.”
Shop this to help restore timber cladding
This natural water-resistant base coat contains an active biocide to reduce algae, mildew and fungal attack. It produces a microporous breathable finish that does not crack, peel, flake or blister.
This mild oxalic acid solution helps remove stains from wood, effectively bleaching the wood to restore it to its more natural color.
These stainless steel impact-resistant cladding pins have an A4 rating, making them ideal for coastal areas with aggressive salt environments.
Best fixing for timber cladding
Choosing the wrong fixings is a common cause of unsightly, unwanted streaks, so using the right one is essential. Martin Dooley, carpentry specialist and founder MD Carpentry Workshopsays, “There are no shortcuts. People try to save money with galvanized nails, but you run the risk of breaking the protective zinc coating. Once that’s broken, the nails rust and stain the wood.”
To make sure this doesn’t happen, Barnes says, “Always use stainless steel. A2 grade for most outdoor environments, A4 for coastal or high-exposure locations.” He explains why, “Stainless steel doesn’t rust and doesn’t react with tannins. It costs a little more than galvanized, but compared to the cost of wood and installation, it’s a small price to pay.”
Martin Dooley is a carpentry specialist and director of the MD Carpentry Workshop. With decades of experience, he specializes in all aspects of carpentry, from bespoke staircases to home renovations.
Does it make sense to replace the fixings?
Replacing the fixings is an option to help ensure they don’t cause any further damage. However, it’s not always a practical or sensible option, Barnes explains, “Removing fixings from installed cladding is dangerous.”
He adds, “If the boards are nailed rather than screwed, recovery is unlikely. The board will split during extraction and require complete replacement.”
However, the real issue isn’t replacing the fixings, but the wood itself, says Barnes, “The big problem is that by the time staining appears, the damage has run the full depth of the board. The tannin reaction is not surface-level.”
How to replace fixings on timber cladding
If you decide that replacing the fixings is the way forward for your timber cladding, there are a few options available. But it is worth noting that this is not a quick or easy task and can be dangerous.
However, if you want to go further, Dooley suggests an approach: “Don’t try to go all out with a claw hammer, you’ll crush the wood fibers and leave a stain.” He adds, “I use the ‘punch-and-fill’ method. Use a pin punch to drive an old nail into the batten about 5mm deep and fill the hole.”
Once this is done, Dooley says, “Place your new stainless steel screw (or nail) above or below the original hole.” However, he warns, “It’s tedious work, but it can save the face of the wood.”
Restoring wood cladding
How you restore timber cladding will depend on the condition of the wood, says Barnes, “For heavy staining, oxalic acid is the most effective treatment for removing discoloration from the wood surface.”
He adds, “For deep staining, expect an improvement rather than a complete restoration. Once wood is exposed to the wrong fixings, it is permanently altered. Your best outcome is a cosmetic improvement, not a return to new.”
However, for lighter marks, Dooley says, “I always recommend Wood Reviver Power Gel. You apply it to wet wood, scrub it with a stiff nylon brush, and it chemically lifts gray cells and neutralizes black iron stains.”
He adds, “After a gentle rinse, the wood feels raw and fresh again. This is your window to apply a high-quality UV oil to prevent the cycle from starting.”
Barnes adds, “For lighter marks, Osmo Wood Reviver Power Gel is worth a try. Let it dry completely before evaluating any product you use.”
Ideally, you want to avoid sanding if possible. However, if necessary, says Buckley, “only use light sanding if the surface is rough or uneven, not as a first step.” penalty Sandpaper grade (120 grit) is usually a good choice. Remember to feather the edges for a smooth finish.
5 tips to maintain a wooden lid
Prevention is better than repair, so maintenance is important to keeping your wood deck looking good. Here, experts offer some smart tips.
1. Deal with problems early
Joe Buckley, Director Heritage Joinery Solutions“Putting the airflow behind the cladding and dealing with minor issues early can actually extend its life rather than waiting until damage becomes apparent,” says.
Joe is the founder and driving force behind Heritage Joinery. He is passionate about preserving the timeless beauty of traditional timber architecture while providing quality and craftsmanship that has stood the test of time.
2. Keep it clean
Barnes recommends regular cleaning: “The single best thing you can do is clean your cladding with a wood reviver every one to two years. It keeps the surface in good condition and deals with any discoloration before it takes hold.”
3. Avoid pressure washers
While using a pressure washer may seem like a good idea it is not recommended. “They can damage the surface of the wood and leave unsightly patterns that are difficult to reverse,” says Barnes. Dooley suggests what you should do instead: “A garden hose and a soft brush are all you need for annual cleaning.”
4. Protect the bottom of the cladding
The base of the board, closer to the ground, needs more attention. “Rain that bounces off the ground gets the most abuse. Give this area extra protection every couple of years,” says Dooley.
Barnes adds another smart move, “Keep plants away from the base of the board. Ivy and overgrown edges trap moisture against the lower course, and the wood never dries properly between wet periods.”
5. Protect the end grain
The end grain of timber cladding is more sensitive and therefore requires additional protection. “Make sure the end grain is heavily sealed with wax or an end grain protector to prevent splitting and rotting,” says Dooley.
FAQ
How long should wood cladding last?
Several factors affect the lifespan of wood cladding. However, if properly installed and maintained, it should last for decades, as Joe Buckley shares, “Well-installed wood cladding should last 40 to 60 years, but the type of wood makes a big difference.”
Buckley continues, “Hardwoods such as oak or larch are more durable and weather resistant, lasting up to 60 years. Softwoods such as pine or spruce require proper treatment to achieve the same lifespan.”
Without treatment, life expectancy can be severely shortened. “Typically, they can only last 15 to 25 years unless they are pressure-treated and regularly maintained, which can extend them to 30 to 40 years.”
Tom Barnes reinforces this point, “Properly installed with stainless steel fixings and proper ventilation, timber cladding is a long-term investment.” He adds, “Larch, British cedar and sweet chestnut will last at least 30 years. More durable options, such as Canadian cedar and brimstone, will last up to 60 years.”
And it’s not always wood that’s the weak point, “where cladding fails early, it’s almost never wood. In our experience, it comes down to batting systems or incorrect fixings”, shares Barnes.
It also suggests an option, “If you want maximum longevity with minimum maintenance, Sulfur cladding Suitable for a serious look. It’s a specification choice for those who want to fit it and forget it.
If you are looking to add new timber cladding or replace your old timber cladding, check out our Consider timber cladding for inspiration. There is an alternative to standard timber cladding shou sugi banA traditional Japanese wood-burning technique that creates a dramatic black finish. our House cladding cost guidelines
