Where’s the job?

Scope of Works

• inspect the existing window sill and reveal to assess rot, moisture and structural soundness

• remove loose or rotten timber or cracked stone and cut back to sound material

• measure and supply a new sill (timber, engineered timber, stone or concrete) to match profile where possible

• fabricate and fit the replacement sill, including bedding, fixing and trimming for a weatherproof fit

• seal, prime and paint or stain timber sills where requested and fit flashings or sealant to external joints

• dispose of waste, tidy the area and advise on moisture sources; use PPE and contain dust during cutting

Typical Cost

Time on Site

Most window sill repairs take 1–4 hours on site; full external replacements or stone sills can take 1–2 days including cutting and curing time. Factors that extend time include first-floor access or scaffold, extent of hidden rot, additional joinery or stone cutting, and waiting for primers or sealants to cure

Questions to Ask Your Tradie

• Have you replaced sills of this material (timber/stone/concrete) before

• Will you investigate and fix the source of moisture as part of the job or only replace the sill

• Do you provide a written quote showing labour, materials and any scaffold hire

• Do you guarantee the work and for how long

• Will you remove and legally dispose of old material and treat rot with preservative

• Do you need access to the property, scaffolding or an elevated platform and who arranges it

How to Avoid Surprises

• clear easy access to the window and a place to store removed sill and materials

• arrange parking close by for the tradesperson’s van or let them know permits are needed

• check for any restrictions in flats or conservation areas that affect replacement materials or scaffold

• remove fragile items from the work area and secure pets

• confirm power availability and whether drying/curing time will require re-entry