Window style is partly aesthetic and partly practical, and the practical side gets ignored until you are trying to clean the outside of a first-floor pane. The main choices in UK homes are casement, tilt-and-turn and vertical sliding sash.
This guide covers what each is good at and where each is a poor fit, particularly for the tenements, villas and post-war semis common across Central Scotland.
How each type works
Casement
Hinged at the side or top and opening outwards, usually with a friction stay. The default UK window, made in every material and price bracket, and the cheapest to buy and repair.
Tilt and turn
Two-position hardware: tilt inwards from the bottom for trickle ventilation, or swing fully inwards for cleaning and escape. Common in flats and popular where the outside face cannot be reached.
Vertical sliding sash
Two sashes sliding past each other in a box or spiral-balanced frame. The traditional look for Victorian and Georgian properties, now widely available in uPVC and timber-alternative materials with modern seals.
Side by side
| Casement | Tilt and turn | Sliding sash | |
|---|---|---|---|
| Typical price | £520 – £780 | £600 – £950 | £800 – £1,300 |
| Cleaning from inside | Partly | Fully | Fully with tilt sashes |
| Ventilation control | Good | Excellent | Excellent (top and bottom) |
| Suits period property | Depends on detailing | Rarely | Yes |
| Fire escape suitability | Good with escape hinges | Very good | Limited |
| Draught resistance | Very good | Excellent | Good with modern seals |
| Obstruction outside | Opens outwards | Opens inwards | None |
| Repair cost | Low | Moderate | Moderate to high |
Choosing for a period property
On a traditional stone-built house, proportions matter more than material. A sash window with the right glazing bar layout and a slim meeting rail will read correctly even in uPVC; a chunky casement in the same opening will not, no matter how good the glass is.
If your property is listed or in a conservation area, the local authority will have a view and may require timber, specific sightlines or particular glass. Check before ordering rather than after.
Practical considerations people forget
- Outward-opening casements clash with garden furniture, bins and paths on tight elevations.
- Inward-opening tilt-and-turn windows clash with curtains, blinds and window-sill clutter.
- Sash windows above a busy pavement are safer because nothing swings out.
- Escape windows in bedrooms need a minimum clear opening — ask the installer to confirm compliance.
- Trickle vents are now required on most replacement windows; decide where they will sit before the frames are made.
Mixing styles across one house
Consistency on the front elevation is worth protecting; the back is more forgiving. A common and sensible compromise is sash windows to the street and casements to the rear, which saves a meaningful amount on a whole-house order without hurting the appearance.
Ventilation, escape and trickle vents
Whichever style you choose, current building standards expect background ventilation on most replacement windows, which usually means trickle vents in the head of the frame. On a sash window they can be discreetly integrated; on a casement they sit in the top rail. Decide where they go before the frames are manufactured, because they cannot be added neatly afterwards.
Bedrooms and upper-floor habitable rooms may also need an escape opening of a minimum clear size, with a sill no higher than a set height above floor level. This is measured on the clear opening rather than the overall frame, and it is the single most common reason a like-for-like replacement has to change configuration.
Sash windows are the weakest performer here, because the maximum clear opening is roughly half the frame. If a bedroom relies on that window for escape, a casement or tilt-and-turn may be the only compliant option, regardless of what suits the elevation.
Getting it specified properly
Whatever style you pick, the details do the work: sightline widths, glazing bar type (astragal on the glass surface looks far better than bars sealed inside the unit), and the colour of the frame inside as well as out. We are happy to walk through those choices on a survey anywhere in Central Scotland.
Common questions
The good ones are, at normal viewing distance, provided the meeting rail is slim and the glazing bars are surface-applied. Cheap ones are not.
Want a straight answer on your own windows or doors?
DM Installations fits and repairs windows and doors across Central Scotland — Cumbernauld, Glasgow, Falkirk, Stirling and the surrounding towns. Free survey, written quote, and an honest answer on whether you need a repair or a replacement.
Related guides
uPVC vs Aluminium vs Timber Windows
Cost, lifespan, insulation and upkeep for the three main frame materials, judged for a wet and windy climate.
Cost guidesHow Much Does Double Glazing Cost?
Typical supplied-and-fitted prices per window, whole-house costs by property size, and the things that quietly push a quote up or down.
When to call a proWindow Rules and Regulations in Scotland
Building standards, warrants, conservation areas and escape windows explained for Scottish homeowners.