How Do You Maintain Wooden Windows and Doors to Keep Them in Good Condition?

Wooden windows and doors will last for decades as long as the finish is kept sound and water is kept off the bare timber. In practice that comes down to looking over the frames a couple of times a year, repainting before the paint film has broken down, and keeping the drainage in the sills clear. Done at those intervals it heads off most of the problems that turn expensive later.

Why Does Timber Need Maintenance in the First Place?

Timber moves. It takes up and gives off moisture as the weather changes through the year, so a frame expands and contracts slightly across the seasons. In a well-made frame that movement is small enough to live with. What matters is the finish over the top of it. While the paint is unbroken, water runs off the frame; once the film thins or cracks and moisture reaches bare wood, decay can start. Keeping that film sound is what a maintenance routine is for.

Modified timbers such as Accoya, which we use as standard, are acetylated so that they take up very little moisture. That gives a high resistance to rot and extends the working life of the timber. The decorative finish is a separate matter. Paint weathers on any exterior joinery, Accoya included, and need refreshing to keep the frame looking right and working properly.

How Often Should You Inspect Wooden Windows and Doors?

Twice a year suits most homes, once in spring and once in autumn before the wet weather sets in. It takes a few minutes a window. Work through the same list each time.

• Look at the finish first. Flaking, peeling, crazing or bare patches all mean the film has gone, and anywhere it has lifted wants attention before the next wet season.
• Check the sealant and putty lines around the glazing beads and the flexible mastic joints at the perimeter of the frame. Cracked or missing sealant is a way in for water.
• Clear the drainage. Drainage slots and weep holes in the sill fill up with dirt, debris and paint build-up, and once they do, water ponds against the frame instead of running away.
• Open and close everything. Hinges, stays, locks and sash balances should all operate smoothly. Stiffness usually means the wood has swollen slightly, and it is one to keep an eye on even if it frees up once the weather dries.
• Look at the putty around the glass. On older units, traditional linseed oil putty should still be sound and tight in the rebate, and any that has started to crumble away needs making good. On modern double-glazed units, look along the edge seal of the unit for signs of misting.
• Give the bottom rail and the sill the most attention. They take the standing water, so they are where trouble shows up first.

What Is the Right Maintenance Cycle for the Finish?

That depends on the product you have used and on how exposed the elevation is. A good quality microporous paint system on a sheltered elevation will go a long time between full repaints. The same system on a face that takes the weather comes round again much sooner. Follow the guidance from the finish manufacturer for the specific product you are using, and let the condition of the finish set the timing. A fixed schedule on its own will either have you painting years early or leaving it long past the point the film went.

How Do You Repaint Wooden Windows and Doors?

Preparing the surface

Most of the durability comes out of the preparation, and it is the stage where a cut corner shows up first.

1. Wash the frame down with warm water and a mild detergent, rinse it thoroughly and let it dry right through.

2. Rub down with a fine-grade abrasive to key the old finish and take off any dust or chalking.

3. Where the finish has lifted or flaked, strip back to bare wood with a heat gun on a low setting or a chemical stripper, then sand the edges of the stripped areas so they feather into the surrounding coat.

4. Fill minor cracks and open grain with a flexible exterior filler, let it cure and sand it flush.

5. Prime any bare timber with the primer or base coat the finish manufacturer recommends before the topcoat goes on.

Applying the finish

Pick a dry, overcast day if you can. Direct sun dries the paint before it has had a chance to level out, which leaves brush marks and can lift the coat. Brush along the grain, and put on two thin coats instead of one heavy one, because the thin coats wear far better.

The end grain is where to take your time, at the bottom rail, the meeting stile and the sill. Those sections soak up the most water and are the first place moisture gets in.

What About the Hardware and Moving Parts?

Hardware tends to get left out of a repaint cycle, and it has a great deal to do with how the window or door actually performs.

• Hinges and stays want wiping clean and a light oil or a proprietary lubricant once a year. Keep grease off friction stays, because it collects grit.
• Locks and espagnolette bolts are generally happier with a dry lubricant on a multi-point lock. Check the supplier’s guidance if you are unsure.
• Sash balances lose spring tension over the years, so on spiral-balance sash windows the mechanism may need adjusting. The sign is a sash that feels heavier to lift than it should. Adjusting it takes the right tensioning tool and is within reach of a competent DIYer.
• Draught seals and weather strips have a finite life, brush pile and rubber compression seals alike. If a window or door has become noticeably draughtier, the seals are the first thing to look at, and replacements are inexpensive and easy to fit.

Should You Worry About Condensation Inside Double-Glazed Units?

Persistent misting between the panes of a sealed double-glazed unit means the edge seal has failed and the unit itself needs replacing. The glass is what has gone there, and the frame around it can be perfectly sound. Get it done reasonably promptly, as a failed unit loses some of its thermal performance.

Condensation on the room side of the glass in cold weather is a different thing. It comes from humidity inside the building and says nothing about the state of the window. More background ventilation and fewer sources of moisture in the room is the answer to that one.

Are There Any Products to Avoid?

Four things to keep away from joinery before you start work.

• Solvent-based gloss used on its own traps moisture vapour in the film, which is why it is not recommended as a standalone system on timber joinery.
• Pressure washing drives water deep into the frame and lifts sound paintwork. Wash the frames down by hand.
• Painting over wet or damp timber leaves moisture trapped under the new coat, and the finish will blister and peel within weeks.
• Filler or paint across the drainage slots closes off the route water takes out of the frame. It is a common mistake when redecorating.

What If There Is Already Some Decay in the Frame?

A soft or punky patch in a bottom rail or a sill, which is where it usually turns up, does not always mean the whole frame is finished. A specialist repair system, using a two-part consolidant and a structural epoxy filler, will in many cases bring a decayed section back to a structurally sound condition. Once it has been painted the repair is hard to pick out.

Where the decay has spread, or the structural sections of the frame have gone, replacement is the more sensible option. On period properties, in conservation areas and on listed buildings, like-for-like replacement in timber is usually what the planning department prefers. Approval rests with your local planning or conservation officer, so confirm what applies to your property before you commit to anything. We make replacement windows and doors in Accoya from our own standard range, and our wooden doors and window ranges are there to talk through with our team.

How Does Maintenance Differ for Accoya Frames?

Accoya’s cell structure absorbs very little moisture. Two things follow from that.

• The finish tends to last longer between repaints, because the wood underneath it barely moves.
• There is no cupping, splitting or swelling of the kind that breaks a paint film on less stable timbers.

Everything else is the same as it is for any wooden frame. You still inspect it, refresh the finish and lubricate the hardware. What changes is that the intervals stretch out and the chance of ever needing structural repair is much lower.

Can Farrar Joinery Help?

We manufacture bespoke timber windows and doors at our factory in Clayton, near Bradford, and we work with homeowners, architects and builders across West Yorkshire, including Leeds, Bradford, Harrogate, Halifax and Huddersfield. Everything we make is new joinery, made to measure. We do not take on repair or restoration work, so the routine above is one for you or your decorator to work through.

When frames have gone past the point where maintenance will hold them, that is the stage to talk to us. Tell us what you have, send any drawings or photographs, and get in touch with our team for a bespoke quote. If you are at the replacement stage, our full window and door range is a good place to start.

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