Alize House Ltd
Window & double glazing company registered in London, Greater London
Registered address
6 SOUTH MOLTON STREET, MAYFAIR,, INTERNATIONAL HOUSE, London W1K 5QF
✓ Active on Companies House
Companies House number16570422
IncorporatedJuly 2025
1 year on the register
1 year on the register
Company typePrivate Limited Company
Trade (SIC 43320)Joinery installation (windows, doors & frames)
Accounts on fileNo accounts filed yet · next due April 2027
Also registered for43341 - Painting; 43390 - Other building completion and finishing; 74100 - specialised design activities
Listed from the public Companies House register, not an endorsement. Quote requests go to FENSA or Certass registered installers covering your postcode, not necessarily this company. Accounts filing category reflects company size under Companies House rules, not service quality. Map location is approximate, based on the registered postcode.
Before you book Alize House Ltd
This page confirms the company is on the Companies House register. It does not confirm FENSA or Certass registration, insurance, or trading status. Check those yourself first.
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Is Alize House Ltd FENSA or Certass registered?
This directory does not confirm registration. Window and door installers self-certify their work against Building Regulations through a Competent Person Scheme — mainly FENSA or Certass — so check the company name or postcode (W1K 5QF) directly on the FENSA or Certass website before booking, and ask to see the certificate number.
How much does window replacement cost in London?
A single uPVC window in London typically runs £300 to £600 supplied and fitted; a full house of 8 to 10 windows is often £3,000 to £8,000 depending on style (casement, bay, sash-look) and glazing spec. Get two or three written, itemised quotes before agreeing to work.
Is new double glazing covered by a warranty?
uPVC frames typically carry a 10 year manufacturer or insurance-backed guarantee, and sealed glazed units are usually guaranteed separately for 5 to 10 years against misting. Register the guarantee after installation and keep the FENSA or Certass certificate — a buyer's solicitor will ask for it if you sell the property.
Does a listing here mean Alize House Ltd is recommended?
No. Companies appear in this directory because they are on the Companies House register under a window/joinery installation trade code. A listing is not vetting, endorsement, or a guarantee that the company is trading or FENSA/Certass registered.
How many window and glazing companies are there in Greater London?
This directory holds 1,616 active window and glazing businesses across 26 towns in Greater London, all from the Companies House register. London accounts for 1,582, among the county's busiest. About 49% of Greater London's registered window and glazing firms were incorporated in the last three years, so weigh incorporation date and FENSA/Certass registration, not just company age.