How to Clean Wooden Windows in an Old Building

The old townhouses in central Lviv still hold an entire stock of wooden windows, often a century old, with double frames and original fittings. They cannot be washed like plastic ones: water that gets into a joint lifts the timber, and ammonia strips the lacquer along with the dirt. The work is slower, but the window outlives any double-glazed unit.

What you need

• Household soap or a mild ammonia-free product — 1 teaspoon per litre
• White vinegar 9 % — 1 tablespoon per litre for the glass
• Linseed oil or furniture wax — once a year

• Three microfibre cloths: glass, timber, polishing
• A soft brush for corners and putty
• A wooden or plastic stick wrapped in a cloth
• Cotton buds for the fittings

Time: 40 minutes per frame.

Step by step

1. Sweep the dust off dry. Brush every surface first: moisture over dust makes a paste that works into the timber.
2. Wring the cloth almost dry. The microfibre should be barely damp — no water should come out of it.
3. Work along the grain. Short sections, drying each immediately with the second cloth.
4. Go carefully around the putty. Old putty at the glass line is brittle and comes away in pieces under pressure.
5. Wash the glass. Vinegar solution on a cloth, keeping the corners dry — that is where water gets under the bead.
6. Dry it completely. Leave the window open for an hour, especially the bottom rail where moisture lingers longest.

Method 2 — the fittings

Brass catches and handles from the nineteenth and twentieth centuries are not cleaned with metal polish: the patina is part of the window, and removing it means losing the original character. A cotton bud with soapy water and a dry polish is enough. Once a year the mechanism gets a drop of machine oil in the hinge, with the excess wiped off at once.

Method 3 — caring for the timber

Once a year, ideally in spring, the wood is treated with linseed oil or furniture wax: a thin coat on a clean dry surface, left to soak in, excess removed. This is not cosmetic — the treatment stops the timber taking up moisture and cracking. Painted frames instead get checked for chips: bare wood under paint starts to rot within a season.

What to avoid

• Plenty of water. Moisture in a joint lifts a layer of timber and the frame stops closing by the next season.
• Ammonia and glass cleaners. They strip lacquer and dry the wood, leaving white marks.
• A steam cleaner. Hot steam blows old putty out of the joints in seconds.
• Abrasives on the glass. Glass in old windows is thinner and softer than modern glass.

Why it is worth the effort

A wooden window in an old building is repairable: a dried-out rail is replaced, the glass reset, the fittings restored. A sealed unit in the same situation is replaced whole. So in older stock maintenance is cheaper than replacement, and what matters in it is dryness and regularity rather than intensity.

The second reason is practical: a double frame with an air gap holds heat as well as a cheap sealed unit, as long as the seal is intact and the sashes close. Half the complaints about cold from old windows are solved not by replacement but by sealing and adjustment.

When to call a cleaner

Wooden frames take twice as long as plastic for the same number of windows, which is exactly why they are more often handed over. With us window cleaning costs UAH 320 per window whether it is wooden or plastic, and that covers glass, frame and sill. The cleaner works with minimal moisture and mild products — the standard for older stock, not a separate service. We do not restore, sand or repaint: that is joinery.

Frequently asked questions

What should wooden windows be washed with?

A mild ammonia-free product on a barely damp cloth, along the grain, dried immediately.

Can old windows be steam cleaned?

No. Steam blows the putty out of the joints and lifts the timber.

Do wooden windows cost more to clean?

No, the price is the same at UAH 320 per window. The difference is in the time, not the rate.

Photo credit

Window with recent and old panes, Tangopaso, Public domain