How do I make sure new windows and doors are secure?

The standard to ask for: PAS 24

PAS 24 is the UK test standard for the security of windows and doorsets. A PAS 24 product has been attacked in a test lab — by hand, with tools and under load — and has to pass every test. Badly fitted, it can still be weak, so ask how it will be installed as well as what it is.

The security rules in the Building Regulations (Approved Document Q) apply to new homes and some extensions, not to replacing the windows in an existing house. Nothing makes your replacement windows PAS 24 unless you ask for it.

GOV.UK: Approved Document Q, security in dwellings (opens in a new tab)

Secured by Design

Secured by Design is a police initiative. Products that carry it have been tested to a recognised security standard and the company is checked. It is not a legal requirement, and approval covers an exact tested product, so check the specific product on the Secured by Design website rather than trusting a logo on a brochure.

Secured by Design (opens in a new tab)

Door locks that resist snapping

Most uPVC and composite front doors lock with a euro cylinder, and the commonest attack is to snap it. Ask for one of these: a TS007 3-star cylinder; a Sold Secure SS312 Diamond cylinder; or a 1-star cylinder fitted with 2-star security handles, which together resist snapping. A 1-star cylinder on its own does not.

Master Locksmiths Association: lock snapping and the most secure cylinders (opens in a new tab)

Glass and frames

Internally beaded: the strips holding the glass in should be on the inside, so a pane cannot be taken out from outside.

Laminated glass: it holds together when broken. Police advice is to use it in glazed doors and in windows a burglar can reach.

Multi-point locking on doors and opening windows, with locking handles, and hinge-side protection so the window cannot be levered on its hinge side.

What to ask your installer

• Are these windows and doors tested to PAS 24? Ask for it on the quote.
• Which cylinder is in the door? TS007 3-star, SS312 Diamond, or 1-star with 2-star handles.
• Is the glazing internally beaded?
• Where will you use laminated glass? At least in glazed doors and windows that can be reached.
• Are the locks multi-point, with locking handles on the windows?
• If you say Secured by Design, which exact product, so I can check it on their site?
• Will you register the work with FENSA (or another competent person scheme), and give me the certificate?

Where this applies

Written for England and Wales. General guidance, not advice on a particular product or home. For the paperwork side — FENSA, guarantees, deposits and cancellation — see the homeowner checklist.

Before you sign: the homeowner checklist →

How these prices compare with other UK guides

Published guides often come in lower. Checkatrade’s window cost guide (last updated July 2026) puts a standard 1,200 × 1,200 mm uPVC casement at £450–£550 plus VAT, about £540–£660 with VAT, and a 3-bedroom house with 12 windows at £5,000–£10,000 plus VAT.

Our figure for the same standard window is about £745 including VAT, for the window itself, fitted, as part of a larger job. It is built from what these jobs typically settle at with established installers. Our estimates then add taking the old frames away, making good and, where needed, access for upstairs windows, which is why the table above, and our £847 to £1,540 a window on an eight-window job, work out at more per window than this. A smaller local firm may quote less than our range; some national companies quote at the top of it.

Whichever figure you use, compare quotes like for like: check each one says whether removal, access, making good and VAT are included.

Checkatrade’s window cost guide →

Planning estimate or quotation?

Every figure on this page is a planning estimate: what a job like this typically costs, for budgeting and for judging the quotes you get. It is not a quotation. A quotation comes from an installer after a survey, when the exact sizes, specification and condition of your house are known.

Facet Pro narrows the estimate to your own house from a photograph of the front — the windows it can see, the wall it can measure against your front door — and says which parts are measured and which are estimated for your house type. Your installer confirms the figure on survey.

How our estimates work →