What Is Double Glazed Door Replacement?
Double glazed door replacement means removing an existing external door and frame and fitting a complete new doorset. That includes the frame, door leaf, glazed panels, threshold and locking hardware, made to measure for the opening. It covers front and back doors, French doors onto a garden, sliding patio doors and bi-folds, whether they lead onto a patio or a conservatory.
Most door enquiries come down to security, draughts or appearance. The trigger is often a lock that has started to fail or a door that sticks every wet winter. Modern doorsets are tested as a complete unit, so the frame, leaf and lock work together rather than relying on a new lock fitted into an old frame.
Signs You Need a Replacement Door
- You have to lift or shoulder the door to get the multi-point lock to engage
- Daylight or draughts come through around the frame or under the threshold
- The door panel has bowed, cracked or delaminated
- Glazed panels have misted, or were never made from safety glass
- A timber door keeps swelling in wet weather and needs planing every autumn
- The lock cylinder or door does not meet current security standards for your insurer
Door Types and Materials Explained
- uPVC doors. These are the most affordable option, often with a decorative glazed or solid panel. They suit back doors and utility entrances.
- Composite doors. A solid insulated core behind a tough glass-reinforced plastic (GRP) skin, usually with a timber-effect grain. Compare the actual doorset construction, thermal performance and security specification.
- Aluminium doors. Slim frames suit wide glazed openings such as bi-folds and sliding patio doors, and match aluminium windows.
- Timber doors. Timber doors suit period and listed properties, and are available with double glazed panels and modern multi-point locks.
- French, patio and bi-fold doors. These glazed door types open living spaces to the garden. Bi-folds fold back fully, sliders save space and French doors suit narrower openings.
What to Include When Asking for a Quote
Say which way the door opens now and whether you want to change it. Changing the side the hinges sit on, or switching from inward to outward opening, affects the frame design and sometimes the steps outside. Measure the opening roughly, and note any side panels or a fanlight above, since these become part of the doorset. For a front door, choose the style, colour and glass design, plus extras such as a letterplate, knocker, spyhole or house number.
If anyone in the household uses a wheelchair or walking aid, ask for a low threshold. Standard doors have a raised sill that can be a trip hazard. For patio or bi-fold doors, mention the floor levels on each side and how the outside ground drains. Water pooling against a low threshold is a common cause of leaks on exposed Norfolk plots.
Ask for the security standard in writing. Ask for evidence of any claimed PAS 24 test performance or Secured by Design accreditation for the complete doorset. Check that anti-snap cylinders are included and that glazing is toughened or laminated as required.
How Much Does Double Glazed Door Replacement Cost?
| Door type | Typical cost |
|---|---|
| uPVC back or side door | £750 – £1,300 |
| Composite front door | £1,100 – £2,400 |
| French or sliding patio doors | £1,600 – £3,800 |
These indicative figures are not quotations. Confirm the total payable including VAT, fitting, access, removal and making good; bespoke or more extensive work may cost more.
Side panels, fanlights, premium hardware and bespoke colours increase the price. Aluminium bi-folds across a wide opening usually cost more than the ranges above.
The Door Replacement Process
- Survey. The installer measures the opening, checks the lintel and floor levels, and confirms the style, colour, glass and hardware.
- Manufacture. The doorset is made to order. Composite doors in stock colours may be quick, while bespoke designs take several weeks.
- Removal. The old door and frame are taken out and the opening is prepared.
- Fitting. The new frame is fixed, the door is hung and adjusted, the threshold is sealed and the locks are tested. Most single doors are fitted in a day.
- Handover. You receive the keys and guarantee paperwork, and you receive any applicable scheme or building control completion documents.
Planning Permission and Building Regulations
Check the proposed appearance as well as the opening size. On a house, a similar-looking replacement often needs no planning application, but flats and restrictions such as Article 4 directions need separate consideration. Works affecting a listed building's special character require listed building consent. Seek advice from the local planning authority for your Norfolk address before ordering. See the Planning Portal permission guide.
Agree the applicable Building Regulations route with the installer before work starts. Relevant checks can include thermal performance, safety glazing, ventilation and escape arrangements. Competent person schemes can certify eligible replacement work; projects outside their scope need an appropriate building control route. New openings, extensions and conversions may be covered by a wider application. Keep the applicable completion documents with your guarantees; see the Building Regulations guide.
How to Choose a Door Installer
- Is the doorset tested to PAS 24, and does it carry Secured by Design accreditation?
- Which lock cylinder is fitted, and is it anti-snap rated?
- Who manufactures the door, and what guarantee covers the slab, frame and hardware?
- Can you fit a low threshold, and how will drainage be handled?
- Will you register the installation for Building Regulations?
- Is my deposit protected if the business stops trading?
Frequently Asked Questions
Can I keep the same opening for new doors in Norfolk?
Often, a made-to-measure doorset can fit the existing opening after a survey. Changing the width or creating a new opening requires additional structural and approval checks.
Does every new door get a FENSA certificate?
No. Scheme eligibility depends on the type of door and project. Ask the installer to confirm which Building Regulations requirements apply and whether a scheme certificate or building control documentation will be provided.