Quick Answer: What Are the Main Types of Windows?
The main window types used in UK homes are casement, tilt and turn, sash, bay and bow, and French windows. Casement windows are the most common and affordable, tilt and turn offers flexible opening and easier cleaning, sash windows suit period properties, and bay or bow windows add extra internal space and light, each with different cost, security, and maintenance considerations covered below.
Casement Windows
Casement windows are hinged at the side and open outward like a door, making them the most widely fitted window type in the UK due to their simplicity, affordability, and good ventilation control.
- Cost: £300 to £600 per window installed
- Pros: Good ventilation, wide opening, cost effective, widely available in uPVC, timber, and aluminium
- Cons: Opens outward, which can be a consideration for windows near pathways or where outdoor space is limited
Tilt and Turn Windows
Tilt and turn windows offer two opening modes from a single handle: tilting inward from the top for secure ventilation, or turning fully inward on a side hinge for cleaning or full opening. This dual function has made tilt and turn windows increasingly popular, particularly in upper floor rooms where cleaning the outside of an outward opening window is more difficult.
- Cost: £400 to £750 per window installed
- Pros: Easier to clean from inside, secure tilt ventilation option, good for upper floors
- Cons: Slightly higher cost than standard casement, mechanism is more complex
Sash Windows
Sash windows slide vertically within the frame and are strongly associated with Georgian, Victorian, and Edwardian period properties, where their traditional appearance is often a requirement in conservation areas.
- Cost: £600 to £1,200+ per window installed
- Pros: Authentic period appearance, good ventilation control by opening top and bottom sashes
- Cons: More expensive than casement, traditional timber sashes need more maintenance
Bay and Bow Windows
Bay windows project outward from the wall in angled sections, while bow windows use a curved, multi pane arrangement, both adding extra internal floor space and additional natural light compared to a flat window of the same wall opening.
- Cost: £1,500 to £4,000+ depending on size and number of panes
- Pros: Extra internal space, increased light, strong kerb appeal
- Cons: Higher cost, more complex installation, more panes mean more potential points requiring maintenance
French Windows and Doors
French windows, essentially a pair of glazed doors opening outward, are typically used where a window opening extends close to floor level, offering both ventilation and direct access to a garden or balcony.
Window Type Comparison Table
| Window Type | Cost Range | Best For | Maintenance |
|---|---|---|---|
| Casement | £300 to £600 | Most homes, budget projects | Low |
| Tilt and turn | £400 to £750 | Upper floors, easy cleaning priority | Low to moderate |
| Sash | £600 to £1,200+ | Period and listed properties | Moderate to high (timber) |
| Bay/bow | £1,500 to £4,000+ | Adding space and light | Moderate |
Choosing a Window Frame Material
Whichever window style you choose, frame material affects both cost and maintenance. uPVC remains the most budget friendly and low maintenance option, aluminium offers slim, contemporary sightlines with excellent durability, and timber suits period properties but requires more regular upkeep. For a full cost breakdown by frame material, see our double glazing cost UK guide.
Window Glazing Options
- Double glazing: Standard for most modern UK installations, balancing cost and thermal performance
- Triple glazing: Additional thermal and acoustic performance at a higher cost, suited to very cold locations or noise sensitive sites
- Acoustic glass: Specifically formulated for noise reduction, useful on busy roads or near flight paths
- Security laminated glass: Adds resistance to forced entry, often specified for ground floor windows
Frequently Asked Questions
What is the most energy efficient window type?
Tilt and turn and casement windows both offer good sealing when closed, and energy efficiency depends more on glazing specification and frame material than the opening style itself, so a well specified double glazed unit in any of these styles will perform well.
Are sash windows more expensive to maintain than casement windows?
Traditional timber sash windows generally need more regular maintenance, including repainting and mechanism checks, compared to uPVC casement windows, though modern uPVC or aluminium sash style windows reduce this maintenance burden while keeping the traditional appearance.
Do bay windows need planning permission?
Replacing an existing bay window with a similar style typically falls under permitted development, but adding a new bay window where none existed before may require planning permission, so it is worth checking with your local authority.
Which window type is best for a period property?
Sash windows are generally the most appropriate choice for genuine period character, and in conservation areas or listed buildings, specific window styles may be a planning requirement rather than just a preference.
Can you mix window types on one house?
While possible, most homeowners aim for visual consistency across the property, particularly on the front elevation, though rear or side windows sometimes use a different, more practical style where visibility from the street is less of a concern.
Expert Insight
Window installers report that tilt and turn windows have seen the fastest growth in popularity among UK homeowners over recent years, largely driven by the practical benefit of being able to clean the outside of upper floor windows from inside the property.
Final Thoughts
Choosing the right window type comes down to balancing your property’s architectural style, budget, and practical priorities such as cleaning access and ventilation. Casement windows remain the sensible default for most homes, while sash suits period properties and tilt and turn offers valuable flexibility for upper floors.
Planning new windows? Get quotes specifying both the window style and the exact glazing specification, since two quotes for the same style can vary significantly based on glass and frame quality alone.
Written by the HometoWorld editorial team, covering home improvement, renovation, and property maintenance across the UK.
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