A well-fitted window keeps out drafts, water, and noise. Whether timber, uPVC, or aluminum, the principles are similar: square, flashed, shimmed, and sealed.
Before Installation
Measure the opening and check it’s plumb & square. Review manufacturer clearances for frame expansion (important for uPVC/aluminum).
Sill & Flashing
Install a sill pan or membrane to direct water away. Proper flashing at the head, jambs, and sill prevents leaks.
Positioning & Fastening
Place the frame on shims at manufacturer-recommended points. Fasten through reinforced sections into structural framing. Avoid over-tightening which can distort frames.
Insulation & Sealing
Use low-expansion foam or a backer rod plus sealant to fill gaps — don’t overfill. Install external flashing and smooth sealant beads for neat weatherproofing.
Common Failures
- No sill pan → leaks.
- Frames fastened poorly → warps or rattles.
- Ignoring thermal expansion → distorted seals.
Maintenance
Check sealant joints annually, clear drainage weep holes, and inspect weatherstrips for wear. Small fixes prevent costly water damage.
