Sash Window Timber Repair London
Traditional sash window specialists serving all London boroughs.
✓ No Call-Out Fee
✓ 5-Year Guarantee
✓ Same-Day Response
✓ Fully Insured
Rotting or damaged timber does not always mean replacement. In most cases, we can repair the affected sections and restore the window to full working order — preserving the original frame, the original proportions, and the character of your property.
🪵 Why Timber Rots
The most common cause of timber rot in sash windows is paint failure. When the paint surface cracks or peels, water penetrates the bare timber — particularly at the base of sashes, on windowsills, and at the meeting rail. Left untreated, wet rot spreads quickly.
- Inspect all timber surfaces — sash rails, stiles, sill, frame
- Probe with a screwdriver to assess depth of rot
- Cut back to sound, dry timber
- Apply two-part epoxy consolidant to stabilise
- Fill with epoxy wood filler and shape to original profile
- Sand, prime, undercoat and finish to a professional standard
🔍 What We Assess
On every job we assess the full condition of the timber — not just the visible damage. Hidden rot in the weight box, at mortice and tenon joints, or behind layers of old paint is identified and treated before it becomes a larger problem.
- Condition of bottom rail — most common rot location
- Sill condition and drainage slope
- Pulley stile bases — often damp from condensation
- Joint integrity at sash corners
- Paint condition across all surfaces
Why London homeowners choose Hartwell Sash
Restore First
We never recommend replacement when repair will do the job. Your original windows are always our priority.
Period Specialists
Victorian, Georgian, Edwardian — we understand Conservation Areas and Listed Buildings across London.
5-Year Guarantee
Every job is covered by a 5-year workmanship guarantee. Fully insured and fully accountable.
Free survey today
We visit your property, assess every window and give you an honest quote — no call-out fee, no obligation, no pressure. Same-day response guaranteed.