Timber Window Maintenance

Why Maintenance Matters

Timber is a natural material. It breathes, expands, contracts, and — if left exposed to the elements — it will eventually absorb moisture and deteriorate. The single most important thing you can do for your timber windows is keep the paint film intact. A well-maintained paint coating prevents moisture from reaching the wood. Once moisture gets in, rot follows.

Our 10-year warranty requires maintenance at least every two years. This is not a bureaucratic hurdle — it is genuinely what the product needs to deliver its full lifespan.

Annual Inspection (15 Minutes)

Once a year — ideally in spring after winter weather — walk around the outside of your property and look at every window. You are checking for:

• Paint condition — any cracking, flaking, peeling, or bare timber? Pay special attention to horizontal surfaces: sills, bottom rails, and the tops of opening sashes. These collect water and deteriorate first.
• Sealant/mastic — check the mastic between the frame and the brickwork. Is it cracked, shrunken, or pulling away? Failed mastic lets water behind the frame.
• Drainage — check that weep holes and drainage channels are clear. Poke a thin wire in if needed. Blocked drainage causes water to pool inside the frame.
• Glass seals — any misting between panes? This indicates a failed sealed unit.
• Operation — do all windows open, close, and lock smoothly? Stiffness usually means a hinge or mechanism needs lubrication.

Bi-Annual Maintenance (Every 2 Years)

Every two years, carry out a full maintenance service. This is what keeps your warranty valid and your windows in excellent condition.

Step 1: Clean

Wash all timber surfaces with warm soapy water and a soft cloth or sponge. Remove dirt, cobwebs, bird droppings, and any green algae. Do not use pressure washers — the high pressure forces water into joints and behind the paint. Do not use abrasive cleaners or solvents. Clean the glass with standard glass cleaner.

Step 2: Inspect and Prepare

After cleaning, inspect the paint closely. If you find areas where the paint has cracked, flaked, or worn thin, lightly sand these areas with 120-grit sandpaper until the surface is smooth. Remove any dust with a tack cloth. If bare timber is exposed, apply a coat of primer before topcoating.

Step 3: Re-coat

Apply a fresh coat of high-quality exterior microporous paint to any areas that need it. Microporous paint allows the timber to breathe — moisture can escape outward without blistering the paint. We recommend Sikkens (the same coating we use in the factory) or equivalent products from Dulux Weathershield or Sadolin.

In most cases, you only need to touch up problem areas — not repaint entire windows. Horizontal surfaces (sills, bottom rails) typically need attention more often than vertical surfaces.

Step 4: Lubricate

Apply a light machine oil or silicone-based lubricant to all moving parts: hinges, friction stays, espagnolette locking mechanisms, and spiral balances (on sash windows). Wipe away excess. This prevents stiffness, reduces wear, and extends the life of the hardware.

Step 5: Check Seals

Inspect all weatherseals and draught strips. If they are compressed flat, cracked, or pulling away from the frame, they need replacing. Contact us or your installer for replacement seals — they are inexpensive and easy to fit.

What Not to Do

• Do not pressure wash timber windows — ever
• Do not use non-microporous paint — standard gloss traps moisture inside the wood
• Do not ignore small problems — a 5mm crack in the paint today becomes a rotten rail in two years
• Do not paint over dirt — clean first, always
• Do not oil the glass seals — lubricant degrades rubber gaskets

Accoya Timber — Less Maintenance

If you chose Accoya timber for your windows, maintenance requirements are reduced. Accoya's acetylation process makes the wood dimensionally stable and highly resistant to rot and fungal decay (50-year manufacturer's warranty on the timber itself). You still need to maintain the paint coating, but the timber underneath is far more forgiving if maintenance is delayed.