Window replacement: process and preparation
Window replacement has six stages: diagnosis, requirements, professional measurement, documented selection, site preparation, then installation and handover. Dimensions, substrate, junctions, ventilation and finishes should be defined before ordering. Installation time depends on the number of openings and building conditions.
1. Diagnosis and objectives
Distinguish failed glazing, worn seals, hardware, frame damage, thermal bridges and installation problems. Then define thermal, acoustic, appearance, maintenance and security objectives.
2. Survey and selection
Approximate measurements may support an initial quotation, but manufacturing sizes require a professional survey. The survey checks level, plumb, substrate, opening, access, shading, sills and junctions.
| Topic | Define | Evidence |
|---|---|---|
| Product | Material, opening, glazing | Description and data |
| Performance | Uw, acoustic, g | Configuration values |
| Installation | Removal, fixing, joints | Junction principle |
| Finishes | Sills, reveals, protection | Included work |
3. Site preparation
Confirm access, storage, internal protection, curtains and furniture. Resolve facade, scaffolding, co-ownership or protected-building constraints before installation day.
4. Installation and handover
After removal, the substrate is checked before fixing and sealing. Handover should test operation, seal compression, drainage, glazing, finishes and cleanliness.
- Operate every sash
- Check seals and adjustment
- Inspect junctions and finishes
- Receive technical documents
- Record defects and deadlines
- Plan maintenance
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Quick answers
How long does replacement take?
It depends on quantity, window type, access, removal, substrate and finishes. A reliable duration requires a site survey.
Can occupants remain in the home?
Often yes when work is phased by area, but dust, noise and temporary openings should be planned with the contractor.
Who takes final measurements?
Manufacturing dimensions should be surveyed or approved by the professional responsible for ordering and installation.
What should handover check?
Operation, adjustment, seals, glazing, drainage, junctions, finishes, documents and any defects.