Installing the Best Windows & Doors in Southeast England

Yes — we’re a FENSA-registered company. Every replacement window and door we install complies with current Building Regulations in England, and we register your installation with your Local Authority. You’ll receive a FENSA certificate for your records and when you sell your property.

We install and repair across Hampshire, West Sussex, East Sussex, Surrey, Berkshire and parts of Kent, Greater London, Sutton, Bromley & Croydon from our base in Crawley, West Sussex. See our Areas We Cover page for the full list.

We offer uPVC and aluminium windows (casement, flush sash, sliding sash, bay & bow, tilt & turn, secondary glazing, triple glazing) and uPVC, composite and aluminium doors (front doors, bi-fold, sliding and French). We also design and build conservatories, porches, and install roof lanterns and flat roof lights.

Yes. We’re an accredited partner for Origin, the UK manufacturer of premium, bespoke aluminium windows and doors. Origin products are engineered for strength, security and slim sightlines and can be tailored to your colour and hardware preferences. Explore: Origin Doors & Origin Windows.

Our systems are designed to meet or exceed current energy-efficiency requirements in England. Options include double and triple glazing, warm-edge spacers and low-E glass. We’ll recommend specifications to reduce heat loss, improve U-values and support ventilation with trickle vents where needed.

Security is standard. Our doors and windows are available with multi-point locking, robust frames and hardware, child-safe restrictors, and laminated safety glazing as required. PAS 24 and enhanced security options are available across many ranges.

Most like-for-like replacements don’t need planning permission, but all work must comply with Building Regulations. Projects in listed buildings, conservation areas, or where you’re changing openings (e.g., adding bi-folds) may need consent. We’ll advise during your survey and can liaise with your local authority if required.

Yes — alongside full installations we offer repairs: replacement double-glazed units, hinges, handles, locks, seals and adjustments on uPVC and aluminium systems. We’ll always discuss the most cost-effective option: repair vs replace.

Lead times vary by product and season. As a guide, most bespoke windows and doors are manufactured in a few weeks after survey sign-off. A standard houseful of windows typically takes 1–3 days to install. We’ll confirm your timeline in your quote and keep you updated throughout.

Absolutely. We use dust sheets and tidy as we go, then remove and responsibly dispose of old frames, glass and packaging. We’ll walk you through operation and care before we leave.

You’ll receive a 10-year insurance-backed guarantee on our installations plus manufacturer warranties on profiles, hardware and sealed units. Your FENSA certificate and documentation are supplied after completion and registration.

Yes — we provide flexible finance options (subject to status). Ask us to include finance illustrations with your quote so you can compare monthly costs vs. paying in full.

uPVC is cost-effective, low maintenance and energy efficient. Aluminium delivers slim sightlines, strength and a contemporary finish — ideal for large panes, sliders and bi-folds. Composite doors combine a robust core with a premium finish for high security and kerb appeal. We’ll recommend the right material during your survey.

Yes — we regularly undertake structural alterations with lintels/steels where required. We’ll assess loads, advise on permissions, and complete the work to Building Regulations with the correct safety glazing near doors and floors.

Yes. We build uPVC and aluminium conservatories and offer conservatory roof replacements (glass, solid and tiled systems) to improve year-round comfort. We also design and install uPVC or brick-built porches to add space, security and kerb appeal.

Choose from a wide palette of foiled uPVC finishes and powder-coated aluminium colours (including dual-colour inside/out). We offer a full range of handles, hinges, glazing bars, decorative glass and thresholds to match your design scheme.

Pricing depends on material, sizes, configuration, glazing spec and access. We provide a free, itemised quote with no obligation and no hidden fees. Request yours here: Request a Quote or Contact Us.

Yes. We’ll specify appropriate trickle vents, advise on background ventilation and recommend acoustic or laminated glass to reduce outside noise where needed — especially near busy roads, schools and flight paths.

1) Arrange a free survey via Request a Quote or call 0800 368 9166 / WhatsApp 07932 960284. 2) Receive your fixed, itemised quotation. 3) We complete a detailed technical survey. 4) Your products are manufactured. 5) Installation by our certified team, followed by registration and your guarantee pack.

Call 0800 368 9166, message us on WhatsApp 07932 960284, email sales@instantwindowsanddoors.co.uk or use the Request a Quote form. We’ll schedule a convenient appointment and provide expert guidance.