Comprehensive Window and Glazing Installation Services
Window installation services and professional glazing solutions deliver precision site surveys, British Standard BS 8213-4 structural anchoring, perimeter thermal insulation, and statutory building regulations compliance across residential and commercial properties. Window Fitters Ltd operates as an established fenestration contractor supplying dedicated labour-only window fitters, sourced trade packages, and full supply and installation services for double-glazed windows, external doors, structural glass facades, and architectural partitions across London and Surrey.
From replacing draughty timber sash windows and multi-faceted bay windows in domestic Victorian terraces to installing multi-storey stick curtain walling systems on commercial developments, every project is executed by directly employed, CSCS-certified installers. We operate as specialist commercial glazing contractors and residential glazing fitters under rigorous site safety governance, maintaining five million pounds public liability insurance and ten million pounds Employers Liability insurance to protect clients, main contractors, and building occupants.
Flexible Glazing Procurement Routes and Contractor Engagement Models
Fenestration projects demand flexible contracting arrangements to align with diverse client budgets, procurement timelines, and material sourcing structures. Window Fitters Ltd provides three transparent commercial routes for homeowners, self-builders, main contractors, and commercial fit-out companies:
- Dedicated Labour-Only Window Fitters and Glazier Teams: Specially designed for main contractors, commercial property managers, and trade clients who have already procured window frames, doorsets, or curtain walling extrusions directly from systems houses or overseas manufacturers. Window Fitters Ltd supplies directly employed, CSCS-carded 2-person teams of labour-only window fitters on fixed day rates of £540 to £580 per day (£540 local, £580 extended), or agreed unit rates for high-volume housing developments. Our glazier teams arrive equipped with precision multi-line laser levels, calibrated glass suction vacuum lifters, heavy-duty glazing shovels, and setting blocks to complete installations strictly to BS 8213-4. As trusted commercial glazing contractors, we provide full site-specific Risk Assessments, Method Statements (RAMS), and COSHH compliance for every subcontract. Discover our labour-only glazing services, hire qualified window fitters, and book structured window fitting teams.
- Sourced Trade Supply with Professional Installation: An optimized hybrid route delivering commercial value for property developers and private homeowners. Our qualified fenestration surveyors carry out on-site laser surveys, verifying structural lintel conditions, aperture squareness, and expansion tolerances. We source high-specification uPVC, aluminium, and timber fenestration profiles directly from leading UK trade fabricators (such as Smart Systems, Origin, Cortizo, VEKA, and REHAU) and glass processors at wholesale trade prices, passing trade discounts directly to the client before our directly employed teams complete the installation. Review our detailed comparison between supply and fit versus supply-only glazing, explore our wholesale trade frame and glass supply options, and examine project pricing in our glazing installation cost guide.
- Complete Supply and Installation Packages: A unified single-point contract providing total project accountability from initial technical survey and CAD shop drawings through factory fabrication, site delivery, BS 8213-4 mechanical fixing, Approved Document L thermal insulation, Local Authority Building Control sign-off, and a written 10-year insurance-backed guarantee. This single-source route provides private homeowners and corporate clients with complete assurance throughout the fenestration lifecycle. Follow our structured 4-step glazing installation process, request a fixed-price technical survey through our online quote request portal, view our domestic residential glazing services, explore our commercial glazing contracting capabilities, and learn more about our written 10-year glazing guarantee.
Core Fenestration and Glazing Installation Services Across Residential and Commercial Sectors
Our professional glazing services cover the complete spectrum of domestic, multi-residential, and commercial fenestration systems:
Residential Window Installation Services: Double Glazing and Triple Glazing Window Installation: Our residential window installation services cover all British home window architectures. We supply and fit high-efficiency casement windows, vertical sliding sash windows, tilt-and-turn units, and structural bay windows. Standard double glazing installation projects feature 24 mm or 28 mm sealed glass packs incorporating low-emissivity (Low-E) soft coatings, 90 percent argon gas fill, and warm-edge spacer bars, achieving whole-window Uw values between 1.2 and 1.4 W/m²K. For bay windows, our installers align welded structural bay pole assemblies and load-bearing jacks to transfer roof and floor loads securely down to sub-cill masonry. For low-energy retrofits and acoustic protection along major traffic corridors, our triple glazing installation services achieve whole-window Uw values from 0.64 to 0.94 W/m²K, reducing heat loss by up to 50 percent and cutting airborne street noise by up to 40 decibels. We install durable uPVC casement windows, heritage vertical sliding sash windows, high-performance triple glazed window units, and slimline thermally broken aluminium windows available in dual-colour powder coatings including contemporary Anthracite Grey RAL 7016.
Door Installation Services: External Entrance Doors and Architectural Patio Systems: Our door installation services combine thermal insulation, weather resistance, and security resistance. We install solid timber core and high-density polyurethane composite entrance doors with reinforced outer frames and multi-point hook locks achieving whole-door Ud values of 1.0 to 1.4 W/m²K under PAS 24:2022 standards. For rear living extensions and garden transitions, our door installation services include fitting multi-panel aluminium bifold doors with stainless steel bottom-rolling tracks and diagonal toe-and-heel leaf bracing, inline sliding patio doors with slimline 20 mm to 29 mm interlock profiles, and classic double French doors. Explore our portfolio of external doors, explore our dedicated door fitters, and read our technical workflows for door installation, composite entrance doors, aluminium bifold doors, sliding patio doors, and French doors.
Commercial Glazing Contractors: Facades, Curtain Walling and Architectural Glazing: Operating as specialist commercial glazing contractors, Window Fitters Ltd provides precision installation for commercial building envelopes, stick curtain walling, structural glass screens, and retail shopfronts. Main contractors and commercial developers rely on our commercial glazing contractors team for expert labour-only installation of client-supplied facade systems. Our glazier teams utilize calibrated glass vacuum manipulators, laser alignment equipment, and structural silicone glazing techniques to fit heavy double and triple glazed facade panels safely and accurately under CDM 2015 regulations. Read our technical guides to commercial glass facade installation, curtain walling installation, and our professional commercial glazing company services.
High-Security Entrance and Architectural Glazed Screens: Full compliance with Approved Document Q and commercial security criteria requires specialist installation. Our dedicated glazier teams fit high-security composite and aluminium entrance doorsets strictly to PAS 24:2022 standards, incorporating multi-point hook locking, anti-snap cylinders, heavy-duty hinges, and laminated security glass. We also install toughened acoustic glass screens for office partitions and reception foyers. Review our credentials on our compliance certificates page.
Internal Glass Partitions and Architectural glass wall panels: We deliver interior architectural glazing services for commercial office fit-outs, educational boardrooms, and luxury residential interiors. Our glazier teams install frameless 10 mm to 15 mm toughened glass partitions and 10.8 mm to 12.8 mm acoustic laminated glass dividing screens achieving sound reduction indices from 36 dB to 50 dB Rw under Approved Document E. Systems incorporate slimline aluminium perimeter channels, clear polycarbonate dry-joints, and integrated frameless pivot doors or sliding glass leaves. We also fit custom-dimensioned low-iron back-painted glass glass wall panels using non-acidic neutral-cure polymer adhesives. Discover our complete range of architectural glass wall panels and soundproofing principles in our acoustic glazing guide.
Glazing Repairs, Sealed Unit Replacement and Hardware Maintenance: Window Fitters Ltd provides sustainable glazing services and maintenance designed to restore thermal performance and security without the expense of full frame replacement. Our fitters de-glaze failed double-glazed sealed units suffering from interstitial condensation and fit new Low-E argon-filled units with warm-edge spacers. We also replace worn friction stays, adjust dropped sashes, renew defective multi-point gearboxes, and provide emergency boarding and securing services following accidental damage. Review our diagnostic guide to failed double glazing seals, our emergency glazing services, and replacement components in our architectural glazing hardware guide.
Glazing Installation Services and Technical Scope Matrix
The matrix below outlines key installation categories, profile specifications, structural anchoring methods, and statutory standards across residential and commercial sectors:
| Installation Service Category | Fenestration Systems & Glass Specifications | Structural Fixing & Sealing Method (BS 8213-4) | Statutory Regulatory Compliance | Typical Applications & Project Sectors | |
|---|---|---|---|---|---|
| Residential Double Glazed Casement & Bay Windows | uPVC, aluminium, and timber casements; multi-faceted splay and square bay windows; 24 mm or 28 mm Low-E argon sealed units; warm edge spacers. | Masonry anchors at 150 mm from corners and 600 mm centres; load-bearing bay pole jacks; bridge packers; low-expansion PU foam; Class 1 neutral silicone. | Approved Document L (Uw 1.2 to 1.4 W/m²K); Approved Document F (8,000 mm² EA trickle vents); Approved Document K; Approved Document A (structural bay load support). | Private domestic renovations, Victorian bay replacements, energy efficiency upgrades, social housing window replacements. | |
| Heritage Vertical Sliding Sash Windows | Traditional timber cords and weights or precision spiral balance uPVC sash windows; slimline heritage sealed units (14 mm to 20 mm) with krypton gas fill. | Box frame side-fixing into timber grounds or masonry reveals; lead counterweight balancing; perimeter brush pile weatherstripping. | Approved Document L (Uw ≤ 1.4 W/m²K); Conservation Area compliance where permitted; Approved Document B (emergency egress escape). | Period townhouse restorations, Victorian and Edwardian renovations, conservation buffer zones, heritage apartment refurbishments. | |
| Triple Glazed High-Performance Windows | Thermally broken aluminium, timber-alternative uPVC, or alu-clad timber profiles; 36 mm to 44 mm triple sealed units with krypton or argon cavities. | Direct frame fixings with thermal break isolators; perimeter expanding foam thermal barriers; airtight internal membrane tape. | Approved Document L (Uw 0.64 to 0.94 W/m²K); Approved Document E (sound reduction up to 40 dB); Passivhaus standard. | Passivhaus new builds, ultra-low energy retrofits, properties adjacent to busy dual carriageways, railways, or airport flight corridors. | |
| Residential Composite & Architectural Entrance Doors | 48 mm solid timber core or high-density CFC-free foam core GRP door slabs; Axorra luxury architectural aluminium entrance doors. | Heavy-duty frame anchoring into structural masonry; sub-cill bedded on DPC; 3D adjustable security flag hinges; low-threshold upstand. | PAS 24:2022; Approved Document Q (security resistance); Approved Document M (accessible max 15 mm threshold); Approved Document L (Ud ≤ 1.4 W/m²K). | Residential front entrances, porch enclosures, new residential developments, luxury architectural entrance statements. | |
| Architectural Bifold & Sliding Patio Doors | Thermally broken aluminium multi-leaf bifold systems; slimline inline sliding doors with 20 mm to 29 mm interlocks. | Sub-floor laser leveling within 1 mm; continuous stainless steel bottom track fixings; diagonal toe-and-heel glass bracing; calibrated bogie rollers. | Approved Document L (Ud 1.2 to 1.4 W/m²K); Approved Document K (Class 1 safety glass); Approved Document Q (PAS 24 multi-point locking). | Rear kitchen extensions, open-plan living apertures, garden terraces, panoramic dining room doorsets. | |
| Commercial Curtain Walling & Stick Facades | Aluminium stick curtain walling systems; structural glass screens; toughened glass shopfronts. | Structural bracket fixings to floor slab edges; laser alignment; pressure plate clamping with EPDM gaskets and snap-on caps; vacuum crane lifting. | Approved Document L (Uw ≤ 1.4 W/m²K); Approved Document E (acoustic insulation); Approved Document K; BS EN 13830. | Multi-storey commercial offices, high-street retail facades, educational institutions, healthcare complexes. | |
| High-Security Entrance Doorsets & Screens | Reinforced aluminium or composite sub-frames fixed to PAS 24; multi-point hook deadbolts; 3-star anti-snap cylinders; overhead closers. | Approved Document Q (PAS 24:2022); Approved Document M (step-free threshold access); Secured by Design compliance. | Residential front entrances, commercial office receptions, apartment building foyers, retail shopfronts. | £850 to £1,450 per doorset | 3 to 4 hours per entrance doorset |
| Internal Glass Partitions & glass wall panels | 10 mm to 15 mm toughened glass or 10.8 mm to 12.8 mm acoustic laminate glass; 6 mm low-iron back-painted glass wall panels. | Extruded aluminium perimeter base and deflection head channels; clear polycarbonate dry-joints; low-modulus neutral-cure adhesive bonding. | Approved Document K (Class 1 safety glass and manifestations at 850-1000 mm and 1400-1600 mm); Approved Document E (36 to 50 dB Rw). | Corporate boardroom suites, office meeting pods, agile workspaces, commercial reception glass wall panels, restaurant mirror feature walls. | |
| Glazing Repairs, Misted Units & Maintenance | Replacement double-glazed sealed units; high-security espagnolette gearboxes; heavy-duty stainless steel friction stays. | Controlled de-glazing of existing frames; rebate cleaning; bridge packer repositioning; neutral silicone weather-proofing. | Approved Document L (restoring sealed cavity thermal performance); BS 8213-4 glazier workmanship. | Condensation-damaged domestic windows, draughty residential casements, commercial door hardware repairs, urgent boarding up. |
Technical Survey and On-Site Installation Standards to BS 8213-4
Achieving structural reliability, thermal efficiency, and long-term weather tightness requires strict compliance with British Standard BS 8213-4:
Three-Point Aperture Laser Survey and Expansion Gap Calculations: Every installation begins with a rigorous technical site survey. Our surveyors measure width and height at three distinct locations (top, middle, and bottom for width; left, centre, and right for height) using precision laser distometers. The smallest aperture measurement is adopted, and dedicated thermal expansion deductions are calculated:
- For standard white uPVC and clear anodised aluminium profiles up to 3.0 metres in overall width, a total deduction of 10 mm (5 mm perimeter clearance per side) is subtracted from the measured opening.
- For dark powder-coated aluminium and foiled uPVC frames (such as Anthracite Grey RAL 7016, Jet Black RAL 9005, or Dark Bronze) which absorb significant solar radiation and reach surface temperatures up to 70 degrees Celsius, a total deduction of 15 mm (7.5 mm perimeter clearance per side) is subtracted to prevent thermal binding and distortion during summer temperature peaks.
- Both corner diagonals are cross-measured to check aperture squareness: diagonal variances must not exceed 2 mm to 3 mm. Existing structural lintels are inspected to confirm that masonry loads do not press down onto window head profiles. For multi-faceted bay windows, our surveyors verify load-bearing bay pole jacks and structural corner posts to guarantee full vertical load transmission down to structural masonry. Detailed survey protocols are documented in our fenestration survey guide and our external wall insulation window fitting guide.
Mechanical Masonry Fixing and Load-Bearing Setting Blocks: Window and door outer frames must never rely on expanding foam or perimeter sealant alone for structural support. Mechanical fixings are placed between 150 mm and 250 mm from frame corners, mullions, and transoms, with intermediate fixings spaced at intervals no greater than 600 mm along jambs. Non-corrosive direct masonry anchors penetrate into solid brickwork or concrete reveals, backed by non-compressible horseshoe setting blocks at each fixing position to prevent frame twisting when screws are torqued. On bifold and sliding door systems, fitters never screw through drainage channels, utilizing concealed base cleats or perimeter fixing brackets. Heavy-duty setting blocks support the cill dead load without bridging the drainage channel.
Diagonal Toe-and-Heel Glazing Geometry: Opening casements, French doors, composite doors, and bifold leaves are susceptible to sash drop if glass is packed incorrectly. Our labour-only window fitters and installation teams implement diagonal toe-and-heel bracing using rigid bridge packers. Packers are installed at the bottom corner adjacent to the hinge pivot and diagonally opposite at the top corner adjacent to the locking handle. By converting the rectangular sash into a rigid structural truss, the deadweight of the heavy sealed glass unit is transferred directly through the diagonal axis down to the bottom hinge, eliminating sash dragging, frame distortion, and locking point misalignment. Learn more in our window installation guide and our door installation guide.
Three-Tier Perimeter Airtightness and Thermal Weather Sealing: To satisfy Approved Document L energy standards and Approved Document C moisture resistance, Window Fitters Ltd applies a three-tier sealing system:
- Internal tier: Continuous airtight sealing using acrylic sealant or vapour-permeable expanding tape to prevent warm interior moisture penetrating into the frame joint.
- Central tier: Low-expansion, flexible polyurethane insulating foam filling the perimeter gap, providing acoustic damping and thermal barrier continuity without expanding excessively to distort frame profiles.
- External tier: High-grade Class 1 neutral-cure low-modulus silicone sealant tooled over a closed-cell polyethylene foam backer rod. The backer rod establishes the correct two-to-one joint width-to-depth ratio, enabling the sealant to expand and contract with seasonal masonry movement while repelling driving rain. Review our safety practices in our site RAMS risk assessment guide and our on-site glazing safety measures.
UK Building Regulations Compliance: Parts L, F, K, Q, B and M
Every fenestration installation carried out by Window Fitters Ltd complies with statutory UK Building Regulations:
Approved Document L (Conservation of Fuel and Power): Under current Approved Document L regulations, replacement windows installed into existing residential dwellings must achieve a whole-window U-value (Uw) of 1.4 W/m²K or better (or a Window Energy Rating of Band B or higher). Replacement external doorsets must achieve a whole-door U-value (Ud) of 1.4 W/m²K or better. For new extensions and new build dwellings, performance targets tighten to Uw 1.2 W/m²K for windows and Ud 1.0 W/m²K for doors. Window Fitters Ltd installs high-performance sealed units combining soft-coat Low-E glass, 90 percent argon gas fill, and composite warm-edge spacer bars that meet and exceed these statutory thresholds. Consult our window U-value guide and our window energy ratings guide.
Approved Document F (Ventilation): Approved Document F mandates that replacement windows must provide background ventilation equivalent to or better than the windows they replace. Where existing windows feature trickle vents or where adequate mechanical extract ventilation is absent, new windows must be fitted with controllable trickle vents. Standard regulations require 8,000 mm² equivalent area (EA) per habitable room (living rooms and bedrooms) and 4,000 mm² EA for wet rooms (kitchens, bathrooms, and utility spaces). We provide slimline over-frame or sash-integrated trickle vents in matching frame finishes to ensure fresh air circulation without cold draughts. Learn more in our trickle vents guide.
Approved Document K (Protection from Falling, Collision and Impact): To protect occupants from accidental glass impact and lacerations, Approved Document K requires toughened or laminated safety glass tested to BS EN 12600 Class 1 (or BS 6206 Class A) in all critical impact zones. Critical zones include any window glazing situated within 800 mm of the finished floor level, any glass panel in an external or internal door situated within 1,500 mm of the floor, and any side panel located within 300 mm of a door edge up to 1,500 mm from the floor. Full-height commercial glass partitions require permanent visual manifestation markers at 850 mm to 1,000 mm and 1,400 mm to 1,600 mm heights with at least 30 percent light reflectance contrast.
Approved Document Q (Security in Dwellings): New dwellings and accessible ground-floor or basement replacement openings must resist unauthorized forced entry under Approved Document Q. All windows and accessible doorsets supplied and fitted by Window Fitters Ltd meet PAS 24:2022 testing standards. Security features include multi-point steel shootbolt locks on casements, hook-bolt locking systems on entrance doors, 3-star TS007 anti-snap lock cylinders, and laminated safety glass (P1A rating under BS EN 356) on accessible glazed doorsets.
Approved Document B (Emergency Egress) and Document M (Accessibility): Under Approved Document B, upper-floor habitable rooms without alternative protected escape stairs require at least one egress window providing an unobstructed clear opening area of 0.33 m², with minimum dimensions of 450 mm in height and width, and a cill height between 800 mm and 1,100 mm from the floor. We fit side-hung casements with specialized egress friction stays that open to 90 degrees for fire escape while incorporating easy-clean slide functions. For main entrances, Approved Document M mandates low-threshold configurations with a maximum upstand of 15 mm and chamfered approaches to facilitate wheelchair and pushchair access.
Local Authority Building Control (LABC) Sign-Off and Certification: Window Fitters Ltd coordinates directly with Local Authority Building Control (LABC) departments and approved private corporate inspectors across London boroughs and Surrey councils. We submit fenestration schedules, arrange on-site inspections, verify structural and thermal calculations, and ensure clients receive official Building Regulations Compliance Certificates essential for legal property deeds and future property sales. Review regulatory pathways in our UK building regulations overview, our building control inspections guide, our Building Regulations compliant versus Building Control comparison, and our certification archive.
Installation Pricing Guide, Labour-Only Day Rates and Procurement Comparison
The pricing table below outlines transparent benchmark rates across our three primary procurement routes, comparing day rates for labour-only window fitters, trade-sourced materials with professional installation, and complete supply-and-fit packages:
| Glazing Installation Category | Labour-Only Window Fitters Rate (2-Person Team) | Sourced Trade Supply + Professional Fit | Complete Supply and Installation Package | Typical Fitting Duration & Output |
|---|---|---|---|---|
| Standard uPVC Casement Windows (e.g. 1200 x 1200 mm 2-vent) | £540 to £580 day rate (£540 local, £580 extended) (or £80 to £130 per window) | £280 to £450 per window | £450 to £750 per window | 1.5 to 2 hours per opening (4 to 6 windows per day) |
| Aluminium Casement Windows (e.g. Smart Alitherm / Origin OW-80) | £540 to £580 day rate (£540 local, £580 extended) (or £110 to £160 per window) | £540 to £720 per window | £750 to £1,250 per window | 2 to 2.5 hours per opening (3 to 5 windows per day) |
| Vertical Sliding Sash Windows (Box sash / spiral balance) | £540 to £580 day rate (£540 local, £580 extended) (or £140 to £220 per window) | £650 to £980 per window | £950 to £1,650 per window | 3 to 4 hours per opening (2 to 3 windows per day) |
| Residential Composite Entrance Doors (48 mm solid core) | £540 to £580 day rate (£540 local, £580 extended) (or £180 to £260 per doorset) | £750 to £1,150 per doorset | £1,200 to £1,950 per doorset | 3 to 4 hours per doorset (2 doorsets per day) |
| Aluminium Bifold Doors (3-panel, 3000 x 2100 mm system) | £540 to £580 day rate (£540 local, £580 extended) (or £550 to £750 per system) | £2400 to £3500 per system | £3600 to £5400 per system | 6 to 8 hours / 1 working day per system |
| Slimline Aluminium Sliding Patio Doors (2-track inline) | £540 to £580 day rate (£540 local, £580 extended) (or £650 to £950 per system) | £2900 to £4400 per system | £4500 to £7500 per system | 1 to 2 working days (vacuum lifting required) |
| Commercial Curtain Walling & Stick Facades (Per m²) | £540 to £580 day rate (£540 local, £580 extended) (or £65 to £110 per m²) | £280 to £450 per m² | £420 to £750 per m² | Project dependent (10 to 20 m² per day team output) |
| High-Security Commercial Entrance Doorsets & Screens (PAS 24) | £540 to £580 day rate (£540 local, £580 extended) (or £190 to £280 per doorset) | £550 to £850 per doorset | £850 to £1,450 per doorset | 3 to 4 hours per entrance doorset |
Installation Cost Drivers and Practical Considerations: Fenestration installation costs vary based on aperture access, structural lintel conditions, glass weight, and building heights. Main contractors engaging our commercial glazing contractors team frequently tender fixed per-unit or per-square-metre rates for commercial curtain walling and shopfronts. Working on upper storeys often requires PASMA-certified mobile access towers or full fixed scaffolding, planned to protect pedestrian walkways and satisfy CDM 2015 site safety regulations. Structural lintel replacements under Approved Document A, requiring temporary Acrow props and Strongboys, add £350 to £700 per opening where concealed timber decay or inadequate masonry support is uncovered during de-glazing. Furthermore, large-format sliding glass panels weighing between 150 kg and 350 kg require specialized dual-circuit glass vacuum manipulators and spider cranes. All redundant timber, aluminium, and uPVC frames removed from site are segregated and transferred to licensed recycling centres under our Environment Agency upper-tier waste carrier registration CBDL650268, achieving 100 percent landfill diversion. Discover itemised project budgets in our glazing installation cost guide, review project timeframes in our double glazing installation time guide, explore seasonal promotions in our special offers section, and consult our commercial contracting terms under B2B glazing contractor services and structured glazing contracts.
Quality Guarantees, Insurance Coverage and Company Compliance
Every window, door, and commercial facade installed by Window Fitters Ltd is backed by clear written guarantees providing long-term structural and functional performance:
- Ten-Year Structural Frame Guarantee: Covering all uPVC, aluminium, and composite outer frame extrusions against structural warping, cracking, corner weld failure, and UV colour fading.
- Five-Year Sealed Glass Unit Guarantee: Protecting double and triple-glazed sealed units against hermetic seal breakdown, optical misting, and internal condensation between panes.
- Five-Year Workmanship Warranty: Covering all installation labour, perimeter weather sealing, structural mechanical anchoring, and thermal insulation against water penetration or draught ingress.
- One-Year Moving Parts Warranty: Covering mechanical hardware components including friction stays, espagnolette gearing, shootbolts, lock cylinders, and door handles against manufacturing defects.
- Comprehensive Insurance Protection: Window Fitters Ltd maintains five million pounds Commercial Public Liability insurance and ten million pounds Employers Liability insurance underwritten by leading UK construction insurers.
- Commercial Statutory Compliance: Registered under the Construction Industry Scheme (Company Registration No. 10415531, VAT GB 258 7412 36), operating with full site-specific RAMS documentation and applying domestic reverse charge VAT procedures in accordance with HMRC VAT Notice 735. Review full guarantee terms on our guarantee page.
Request a Free Glazing Quote and Itemised Estimate
To book dedicated labour-only window fitters for a commercial development or to arrange a complete supply and installation package for a residential property, our Croydon technical office provides fixed-price quotes based on architectural drawings, tender schedules, or on-site laser surveys. Contact our estimating team to discuss your glazing project:
- Registered Office: Window Fitters Ltd, 139 Wentworth Road, Croydon, CR0 3HZ
- Telephone: 020 3411 0589
- WhatsApp Estimating: Send drawings and photos via WhatsApp
- Email: info@windowfitters.uk
- Online Quote Portal: Request a technical quote online
- Geographic Coverage: Greater London, Surrey, and surrounding regions via Croydon HQ travel-time tiers (<15m local at £540/day, 15-45m extended at £580/day, >45m outer Surrey with half-day minimum) of our Croydon office.
Explore our recent completed projects in our glazing project gallery and commercial projects directory, and read technical articles on our fenestration blog.
Frequently Asked Questions About Glazing Installation Services
Explore our complete fenestration capabilities, commercial subcontracting routes, residential fitting standards, and trade glazier deployment.
What fenestration and glazing installation services does Window Fitters Ltd provide? +
Window Fitters Ltd provides supply-and-fit and labour-only installation services for residential windows, entrance doors, architectural patio doors, commercial curtain walling, structural glass facades, frameless glass partitions, and misted sealed unit repairs across London and Surrey.
What is the difference between labour-only fitting and complete supply and installation packages? +
Under our labour-only service, directly employed CSCS glazier teams install client-supplied window frames, doorsets, or curtain walling on fixed day rates (£540 local under 15 minutes, £580 extended 15 to 45 minutes per day for a 2-man team; £260 to £290 for a single fitter) or per-unit rates. Complete supply and installation packages provide an end-to-end contract covering technical laser survey, trade frame procurement, site installation to BS 8213-4, Building Control certification, and a 10-year guarantee.
What thermal performance and U-values do your replacement window installations achieve? +
Our replacement double glazing installations achieve whole-window Uw values between 1.2 and 1.4 W/m²K, meeting and beating the Approved Document L standard of 1.4 W/m²K. Our triple-glazed window systems achieve Uw values between 0.64 and 0.94 W/m²K for Passivhaus and low-energy projects.
Do your installers handle Building Control compliance and certification? +
Yes. We coordinate directly with Local Authority Building Control (LABC) or approved private inspectors to arrange site inspections and secure legal Building Regulations Compliance Certificates covering Approved Documents L for energy conservation, F for ventilation, K for impact safety, B for fire egress, and Q for security.
Can main contractors hire your glazier teams for commercial subcontracts? +
Yes. We operate as a specialist B2B commercial glazing subcontractor under standard JCT and NEC contract terms. Our directly employed glazier teams hold valid CSCS cards, complete site-specific RAMS and heavy glass lifting plans, and are backed by £5,000,000 public liability and £10,000,000 Employers Liability insurance.
How are window and door apertures surveyed to ensure correct expansion tolerances? +
Surveyors use precision three-point laser measurements across height and width, adopting the smallest dimension and deducting standard thermal expansion tolerances to BS 8213-4: 10 mm overall for white uPVC and aluminium under 3 metres, and 15 mm overall for dark powder-coated profiles such as RAL 7016 Anthracite Grey to accommodate solar thermal expansion.
Author & Technical Reviewer: Marian Gheorghe
Head Installer & CEO, Window Fitters Ltd
Marian Gheorghe is the Active Director and Team Leader Installer at Window Fitters Ltd. With over 15 years of hands-on experience, he oversees technical safety and UK Building Regulations compliance for all residential and commercial glazing contracts.
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Verified Google & MyBuilder Reviews
"Stunning Sash Windows in Croydon"
"Marian and his team replaced our old Victorian sash windows. They were clean, fast, and the double glazing has completely blocked out the street noise. Highly recommended!"
"Excellent Bifold Doors in Bromley"
"Installed beautiful grey aluminium bifold doors for our new kitchen extension. Smooth gliding mechanism and great insulation. The best quote we got in Kent."
"Perfect Front Door Upgrade in Sutton"
"Very happy with our new composite door installation. Excellent lock security and high-quality GRP slab finish. Fast half-day fitting and no mess left behind."