Casement windows
The standard British window. Side or top hung sashes on friction stays, in any combination of fixed lights and openers you like.
Windows
Made-to-measure windows, in uPVC or slimline aluminium
Six frame styles, any RAL colour, A-rated glazing as standard. We measure every opening ourselves and have the frames manufactured to those exact sizes — no packing out gaps with foam and hoping for the best.
First decision
uPVC or aluminium?
Most replacement windows should be uPVC. Aluminium earns its extra cost where you want slim frames and a lot of glass. Here's the honest comparison.
| uPVC | Aluminium | |
|---|---|---|
| Frame width on show | Around 70–90mm | Around 45–65mm, so more glass |
| Whole-window U-value | From 1.2 W/m²K double, 0.8 triple | From 1.4 W/m²K double, 1.0 triple |
| Window Energy Rating | A to A++ available | A to A+ available |
| Maximum practical sizes | Good for typical domestic openings | Better — spans wider without a mullion |
| Colour | Foiled finishes, 20+ standard options | Powder coated to any RAL, dual colour available |
| Maintenance | Wipe clean, occasional hinge oil | Wipe clean, occasional hinge oil |
| Expected life | 25–35 years | 35–45 years |
| Relative cost | Baseline | Roughly 40–70% more |
| Best for | Replacement windows, best value per unit of heat saved | Extensions, large openings, modern elevations, bi-folds |
Not sure which way to go?
A common answer is both: uPVC on the bedrooms where nobody's looking at the sightlines, aluminium on the rear extension where you want the glass. We'll price it either way so you can see the difference in pounds rather than in theory.
A note on triple glazing
It's genuinely warmer and quieter, and it adds roughly 15–25% to the cost. On a north-facing wall or a road-facing bedroom it's usually worth it. On a sheltered south-facing elevation the payback is much longer. We'll say which we'd choose.
The range
Six window styles
All available in uPVC. Casement, tilt & turn and the slim range are also available in aluminium.
Flush sash windows
The sash sits level with the frame rather than proud of it, so it reads like a traditional timber window. The right answer for conservation areas.
Tilt & turn windows
One handle, two functions: tilt in at the top for secure background ventilation, or swing fully inward so you can clean the outside from indoors.
Bay & bow windows
Three, four or five facet bays, with the load properly carried on jack posts or a structural head. We check what's holding the wall up before we take the old one out.
Vertical sliding sash
Both sashes slide and tilt for cleaning. Run-through horns, deep bottom rails and Georgian bars if you want the full period look.
Slimline aluminium
Thermally broken aluminium with sightlines from 45mm. Spans wider than uPVC without a mullion, and takes any RAL colour including dual-colour inside and out.
Glass & energy
What's actually in the sealed unit
Most of the heat a window loses goes through the glass, not the frame, so this is the part worth understanding. Every unit we fit is built the same way unless you ask otherwise.
- Low-emissivity inner pane A microscopically thin metal oxide coating that reflects heat back into the room instead of letting it radiate out.
- Argon-filled cavity 16–20mm of argon rather than air. Denser gas, less convection, better insulation.
- Warm-edge spacer bar A composite spacer instead of aluminium, which stops the edge of the glass acting as a cold bridge. This is where condensation starts.
- Toughened or laminated where required Doors, side panels, anything below 800mm and anything near a door edge. Part K of the Building Regulations, not an upsell.
| Option | When it makes sense |
|---|---|
| Standard A-rated double | The default. Right for most rooms. |
| Triple glazed | North-facing walls, road noise, new extensions. |
| Acoustic laminated | Main roads, flight paths, railway lines. |
| Obscure / patterned | Bathrooms and en-suites. Several patterns to choose from. |
| Solar control | Big south or west-facing glazing that overheats in summer. |
| Self-cleaning | High or awkward windows you can't safely reach. |
| Georgian or astragal bars | Period properties and conservation areas. |
| Leaded or stained detail | Matching an existing front elevation. |
Finishes
Colours people actually choose
These are our most requested finishes. uPVC can be foiled on the outside only, keeping white inside, which many people prefer. Aluminium goes to any RAL.
- WhiteGloss uPVC
- Anthracite greyRAL 7016
- Jet blackRAL 9005
- CreamRAL 9001
- Chartwell greenHeritage
- Agate greyRAL 7038
- RosewoodWoodgrain foil
- Golden oakWoodgrain foil
- Fir greenRAL 6009
- Wine redRAL 3005
- Steel blueRAL 5011
- SilverRAL 9006
Handles and hinges come in white, chrome, satin, black, gold and antique brass. We bring physical samples to the survey — colour on a screen is never quite colour in daylight.
Security
How the windows are locked down
Roughly a quarter of domestic break-ins go through a window. The hardware matters as much as the frame.
Multi-point shootbolts
Espagnolette locking that engages at several points up the sash rather than one central catch, so the whole frame is held.
Internally beaded
The glazing beads are on the inside. Nobody can lever the beading off outside and lift the sealed unit out of the frame.
Key-locking handles
Standard on ground floor and anything reachable from a flat roof or garage. Useful for insurance, useful with children in the house.
Restrictor stays
Hold an opener at a safe gap for ventilation without leaving it wide enough to climb through. Child-safe on upstairs windows.
Fire escape hinges
Where a bedroom window is the designated means of escape, we fit easy-clean egress hinges that open to the required clear width.
Laminated glass option
An interlayer that holds the pane together when it breaks. Worth it on accessible ground floor windows and anywhere overlooked by an alley.
Fitting day
How we replace a window properly
Anyone can get a frame into a hole. The difference between a window that lasts thirty years and one that leaks in year three is what happens around the frame.
- Floors and furniture sheeted, one opening worked at a time so the house is never open.
- Old frame cut out rather than smashed out, protecting the plaster reveal and the outside render.
- Opening checked for a sound lintel and a dry cill. If something's rotten or cracked, we tell you before the new frame goes in.
- New frame packed and mechanically fixed to the structure, checked plumb, level and square on all three axes.
- Perimeter foamed and then sealed with low-modulus silicone inside and out. Drainage slots left clear.
- Sashes adjusted, gaskets seated, hinges and locks tested through a full cycle.
- Old frames and glass taken away, reveals made good, and everything cleaned before we leave.
Window questions
Worth knowing before you order
Usually yes. Since the 2022 changes to Part F of the Building Regulations, if the window you're replacing had background ventilation then the new one has to have at least as much. In practice that means trickle vents on most replacements.
They're less obtrusive than people expect, and they're what stops a newly sealed house filling up with moisture and growing mould in the corners. We'll show you where they need to go at survey.
No — it's the opposite. External condensation means so little heat is escaping through the glass that the outer pane drops to the temperature of the night air and dew forms on it, the same way it does on a car windscreen.
It's a sign the low-emissivity coating is doing its job. It burns off as the sun comes round. Condensation between the panes is a genuine fault, and that's covered by your guarantee.
Usually very closely. Vertical sliding sash with run-through horns and a deep bottom rail, or flush sash with astragal bars, gets you most of the way there in uPVC at a fraction of timber cost.
If you're in a conservation area or the building is listed, the council may specify timber or restrict what's acceptable. We'll tell you at survey rather than after you've paid a deposit.
If you're coming from single glazing or from failed units from the 1990s, yes, noticeably. If your current windows are decent modern double glazing, the saving is real but modest and the honest reason to replace is comfort, noise, security or appearance rather than payback.
We won't quote you a fictional annual saving. Anyone who does is guessing at your heating habits.
Yes to both. Single window replacements are fine, and if a frame is sound but the unit has misted we can just swap the sealed unit, which is far cheaper.
Bear in mind that a new white frame next to twenty-year-old white frames rarely matches perfectly — uPVC weathers. We'll be upfront about that before you decide.
Get a written quote for your windows
Free survey, itemised price with sizes and glass specification listed, valid for 60 days. No deposit until you've seen it in writing.