1. Size and system
Bigger panes need deeper frames, thicker glass and more people or machinery to handle them, so the price rises faster than the area once panels get large. The type of system matters too: slim sliding doors are usually a little cheaper than lift & slide, and every extra bi-fold leaf adds hinges, rollers and a frame. To compare materials, see materials compared.
2. Glass
- Double or triple: triple glazing insulates better but is heavier, which can mean stronger hardware.
- Laminated glass for safety and security, and where it is required at low level or overhead.
- Solar control for south- and west-facing glass and roof glazing.
- Acoustic glass near busy roads or flight paths.
Each pane can have its own specification, so you only pay for triple or acoustic glass where it does a job.
3. Hardware, colour and security
Standard colours and hardware cost less than special finishes.
4. The opening and the site
- Thresholds. A flush threshold needs a recessed track and drainage built into the floor.
- Structure. The beam above a wide opening is designed by a structural engineer and is part of the building work; its stiffness limits how big the doors can be.
- Access. Large panes on a terraced street may have to go through the house, or over it with a crane or a lifting machine. The survey checks the route.
- Height and floors. Upper floors, basements and balconies need more handling and sometimes access equipment.
5. Where to save
- Fix the opening size early, so the doors are designed for it rather than adapted later.
- Keep sliding panels within the system’s usual limits, rather than at the maximum.
- Use triple, acoustic or solar control glass only where it does a job.
- Choose one system for the whole elevation, so frames and details repeat.
6. What a quote should show
- Sizes and configuration of every opening
- System and material, colour and hardware
- Glass for each pane, and the U-value
- Threshold detail
- Survey, delivery and installation
- What is by others: the beam, making good, decorating
- Payment stages
Send us the sizes or a drawing and we prepare an individual quote. The formal quote follows a technical check. Not sure what you need yet? Start with our guide for homeowners.
Questions
Why don’t you publish prices?
Because two openings of the same width can differ a lot: glass, threshold, access and structure all change the price. We quote each project individually from its sizes or drawings.
Is triple glazing worth it?
It depends on the opening. Triple glazing helps most on large north-facing glass and where you want a quieter room; it also adds weight. Double glazing that meets Part L is often enough in London.
Does a flush threshold cost more?
Yes. It needs a recessed track and drainage built into the floor, and the floor build-up has to be planned around it.
What is usually not in a window or door quote?
Building work around the opening: the structural beam, making good the reveals, plastering and decorating. Check what each quote says is by others.