Window & Door Fitting FAQs

Building Regulations compliant self-certification applies strictly to replacement windows and doors installed in existing structural openings of similar dimensions without structural alterations. For any project involving structural modifications such as widening apertures, inserting steel lintels, removing load-bearing masonry for bifold doors, building new extensions, or commercial glazing, Local Authority Building Control (LABC) inspection and sign-off is legally mandatory. We coordinate directly with your local council building control department across London and Surrey to submit Building Notices, schedule site inspections, and obtain official Building Regulations Completion Certificates.

Yes. We provide complete trade supply and fitting services as well as dedicated labour-only installation teams. If you have already ordered windows or doors from an online supplier, trade counter, or specialist fabricator, our CSCS-carded glazier teams install them on transparent fixed day rates (£540 per day locally under 15 minutes, £580 per day for extended travel 15 to 45 minutes for a 2-man team; £260 to £290 for a single fitter) or fixed per-unit rates, providing all required glazing packers, suction lifters, and fixings.

Yes. We maintain direct relationships with major UK trade extruders and fabricators of uPVC, aluminium, and timber systems including Smart Systems, Cortizo, Origin, Schüco, AluK, and Solidor. We help clients procure high-specification frames and glazing units directly at trade wholesale rates, saving homeowners and builders 30% to 50% compared to retail showroom quotations.

We handle both full installations and targeted glazing repairs. In over 80% of properties with sound outer frames, full replacement is unnecessary. Our glaziers carry out glass-only sealed unit replacements for misted double glazing, fit new austenitic stainless steel friction stay hinges, replace jammed multi-point lock gearboxes, renew perished weatherstrip gaskets, and re-pack dropped door sashes.

Installation costs vary based on dimensions, materials, structural access, and whether you choose labour-only fitting or a complete supply and installation service. For labour-only fitting, standard casement windows cost £35 to £65 per unit, entrance doors cost £150 to £250, and bifold doors cost £60 to £90 per leaf. Complete supply and fit packages range from £450 to £750 for standard uPVC casements, £850 to £1,400 for aluminium casements, and £1,200 to £2,200 for composite front doors.

Fitting a single standard replacement casement window typically takes 1.5 to 2 hours. Replacing all windows in a standard 3-bedroom house (8 to 10 windows) takes an experienced 2-man glazier team 1 to 2 working days. A pre-hung composite entrance door takes 3 to 4 hours, while a 3-pane to 5-pane aluminium bifold door set takes 1 full working day including track levelling, toe-and-heeling, and weathersealing.

Modern uPVC and powder-coated aluminium window frames have an expected service life of 25 to 35 years when maintained with periodic hinge lubrication and drainage clearance. Double-glazed sealed units (IGUs) have an average lifespan of 15 to 25 years before thermal pumping and natural desiccant saturation cause edge seal failure. When a unit mists up, a quick 20-minute glass-only swap restores full thermal efficiency without replacing the frame.

The most common issues include misted condensation between panes (solved by replacing the sealed unit), cold draughts around sashes (solved by replacing worn friction hinges or compressed rubber gaskets), dropped sashes catching on frame keeps (solved by diagonal toe-and-heel re-packing), and water pooling on cills (solved by clearing blocked frame drainage weep slots).

Our installation teams lay heavy-duty protective floor runners from the front door to every working aperture, cover furniture with clean dust sheets, and wear protective boot covers inside living spaces. We remove old frames inward wherever possible to protect exterior render, vacuum brick and plaster dust continuously, and remove all old glass and debris daily under Environment Agency waste carrier registration CBDL650268.

Inaccurate fitting is prevented by conducting precision technical site surveys. Our surveyors measure every structural brick-to-brick aperture in three separate locations for width and height, verify diagonal squareness, and deduct exact 10 mm overall expansion tolerances (5 mm per side). This ensures new frames fit squarely without forced masonry cutting or excessive perimeter gaps.

External doors should be installed after wet masonry, structural knocking-through, and wet plastering are finished, which seals the building envelope and allows internal moisture to dry out. However, they should be fitted before final floor finishes (such as tiling, engineered wood, or carpet) and final mist-coat painting, allowing floor heights to be checked against Document M threshold allowances.

Sticking doors and latch misalignment occur when frames are fitted out of square or sashes drop under their own weight. Our fitters install outer frames plumb and level using optical laser levels and high-density composite shims. We glaze door leaves using diagonal toe-and-heel bridge packers and calibrate 3D adjustable flag hinges for compression, height, and lateral alignment.

Qualifying supply and fit installations carry a 10-year manufacturer-backed frame warranty and a 5-year hermetic seal warranty on double-glazed glass units. We hold £5,000,000 Commercial Public Liability Insurance and £10,000,000 Employers Liability Insurance. All on-site fitters are directly employed, background-checked, and hold valid CSCS qualifications.

Yes. Under Approved Document L of the Building Regulations, every replacement external door is a controlled fitting and must achieve a minimum thermal performance of Ud 1.4 W/m²K or Door Energy Rating Band C. Where a replacement door involves widening an opening, removing a chimney breast, installing a new load-bearing lintel, or fitting within a new extension, Local Authority Building Control sign-off is legally required.

Hanging a standard internal timber door typically costs £60 to £120 per door for labour only, depending on whether handles, latches, and hinges require initial mortising. Installing an external pre-hung composite door set ranges from £150 to £250, while heavy multi-panel aluminium bifold or sliding doorsets range from £350 to £650 for labour and precision alignment.

An experienced joiner typically hangs 4 to 6 standard internal timber doors per day, including cutting hinge recesses, fitting tubular mortise latches, and installing handle furniture. For external pre-hung composite or aluminium doorsets, a team fits 1 to 2 complete units per day due to perimeter masonry fixings, threshold levelling, expanding foam insulation, and weatherseal caulking.

Common door fitting errors include failing to fit frames plumb and square (leading to frame twist and latch binding), overtightening masonry fixings without solid shims (bowing outer jambs), neglecting diagonal toe-and-heel packing in glazed leaves, fitting thresholds without DPC damp-proof bridging, and trimming engineered door edges past their structural timber lippings.

Under Approved Document K and BS EN 12600, impact-tested safety glass (toughened or laminated) is mandatory in all critical locations: in any door panel up to 1,500 mm from finished floor level, in side panels within 300 mm of a door edge up to 1,500 mm from floor level, and in any window glazing situated below 800 mm from finished floor level.

Yes. Under the revised Approved Document F regulations, replacement windows must be fitted with background trickle ventilators providing a minimum equivalent area of 8,000 mm² for habitable rooms and 4,000 mm² for wet rooms such as kitchens and bathrooms, unless the home has a verified continuous mechanical extract ventilation (MEV) or mechanical ventilation with heat recovery (MVHR) system.

Under Approved Document L, replacement windows installed in existing domestic dwellings in England must achieve a whole-window Uw value of 1.4 W/m²K or better, or achieve a minimum Window Energy Rating (WER) of Band B. For new extensions or new builds, the notional target is whole-window Uw 1.2 W/m²K.

Under Approved Document B, emergency egress windows serving habitable upper-floor bedrooms must provide an unobstructed openable area of at least 0.33 m², with a minimum clear width and height of 450 mm in both directions. The bottom of the openable area must sit between 800 mm and 1,100 mm above finished floor level, fitted with 90-degree egress easy-clean friction stay hinges.