Updated June 2026 · CW Doors & Windows
How to choose replacement windows — the decisions that matter
Most homeowners get talked through 30 options when only 6 decisions actually matter. Here's the short list — what to spend on, what to skip, and how to spot a bad quote.
1. Frame material
uPVC for almost all homes. Aluminium for large picture windows or contemporary extensions. Timber only for conservation areas or listed properties.
2. Energy rating
A-rated minimum. A++ is marginal real-world improvement over A on standard double glazing. Don't pay a premium for A++ unless you have very north-facing rooms.
3. Glass spec
Standard 28mm A-rated sealed unit for most rooms. Laminated inner pane on ground-floor and accessible windows for security. Acoustic asymmetric units on road-facing elevations.
4. Opening configuration
Egress (fire escape) windows are required on upstairs bedrooms — usually a top-opening casement. Tilt-and-turn for ease of cleaning on awkward access. Sliding sash for period properties.
5. Colour and finish
White is cheapest. Anthracite grey, black, and woodgrain effects add 10–15%. Specify dual colour (different inside/outside) if you want white interiors with a coloured exterior.
6. The installer
Matters more than the brand of window. Look for: 10+ years trading, FENSA registered, own fitters not subcontractors, written itemised quote, insurance-backed guarantee, references in your area.
Matching the window to the house
Casement windows suit most 1930s semis and modern homes and start from £450 fitted. Flush casements give a more traditional look from £520. Sash windows suit Victorian and Edwardian houses from £780. Tilt and turn windows start from £560 and are easy to clean from inside.
Colour matters too: our windows come in a wide range of RAL finishes, including dual colour, so the outside can match the street while the inside stays white.
Get a free written quote
Family-run Leicester installer, 40+ years, 10-year insurance-backed guarantee. Clear, itemised written quotes.
Request your free quoteFrequently asked questions
Get your free quote
No pressure, no salesmen, itemised in writing.