Glazier or window company? Who to call for which job in London
By Glazing London,
Advice · Choosing who to call
By Glazing London, Wood Green N22 Published 7 November 2026 4 min read
"Glazier" and "window company" get used as if they mean the same thing, and calling the wrong one can mean a sales visit for a job that needed a pane of glass. Here's who does what, from a London firm that does both.
Quick answer
Call a glazier when the problem is the glass: broken, cracked, misted, the wrong safety glass, or a pane that needs cutting to size. Call a window company when the frame has failed or you want new windows or doors. A firm that does both, like our glaziers in London, tells you honestly which one you need.
Jobs for a glazier
- Broken or smashed glass, including 24/7 emergency glazing and boarding up after a break-in or storm.
- Misted double glazing, where the sealed unit has failed but the frame is fine: see misted double glazing repair.
- Glass cut to size for picture frames, tables, cabinets and DIY reglazing: glass cut to size.
- Safety glass upgrades in doors and low-level panes.
- Secondary glazing for sash windows and listed buildings: secondary glazing.
Jobs for a window company
- Rotten, warped or failed frames that can't hold a new unit.
- New windows and doors, from sash and casement to bifolds: window and door installation.
- Full double glazing for a home: double glazing in London.
The grey area: repairs
Sticking doors, dropped sashes, broken locks and failed hinges are repair jobs, not replacement jobs. They are often fixed in a single visit for a fraction of the cost of a new window. Our window and door repairs team will tell you if a repair will last or if replacement is the better spend.
Key takeaway
Start with the problem, not the product. If only the glass is wrong, a glazier fixes it. If the frame has failed, you need a window company. A firm that does both has no reason to sell you the bigger job.
Not sure which you need?
Send a photo by WhatsApp and a glazier tells you whether it's a glass job, a repair or a replacement, with a fixed price.
Related reading & services
How to choose a glazier in London
Eight checks before you book anyone.
Glazier cost in London
Typical prices and how to avoid paying for things you don't need.
Misted double glazing: what to do
Why sealed units fail, and why glass-only replacement usually wins.
Glazier questions
What is the difference between a glazier and a window fitter?
A glazier works with the glass itself, cutting, fitting and replacing panes and sealed units in existing frames, including emergency glass repair. A window fitter installs whole new frames. Many London firms, Glazing London included, do both, so one survey covers either.
Can a glazier replace just the glass in a double glazed window?
Yes. If the frame is sound, a glazier replaces only the sealed unit, which is usually far cheaper than a new window and keeps your existing frames and hardware.
Do I need a FENSA-registered installer?
For replacement windows and doors in England, the installation must meet Building Regulations, and a FENSA-registered installer can self-certify that. Glass-only replacement in an existing frame does not normally need it. Glazing London is FENSA approved.