Dsj Interiors N.i Ltd
Window & double glazing company registered in Belfast, Belfast
Registered address
UNIT B15 CLARA HOUSE, 37A UPPER DUNMURRY LANE, DUNMURRY, Belfast BT17 0AA
✓ Active on Companies House
Companies House numberNI687726
IncorporatedApril 2022
4 years on the register
4 years on the register
Company typePrivate Limited Company
Trade (SIC 43320)Joinery installation (windows, doors & frames)
Accounts on fileMicro-entity accounts (smallest filing band) · last filed April 2025 · next due January 2027
Also registered for16230 - Manufacture of other builders' carpentry and joinery; 41202 - Construction of domestic buildings
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 Dsj Interiors N.i 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 Dsj Interiors N.i 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 (BT17 0AA) directly on the FENSA or Certass website before booking, and ask to see the certificate number.
How much does window replacement cost in Belfast?
A single uPVC window in Belfast 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.
What is a FENSA or Certass certificate and why does it matter?
It's proof the window or door installation meets Building Regulations (thermal performance, safety glazing, ventilation) without a separate council building control sign-off. Without one, selling the property can mean paying for retrospective building control inspection or indemnity insurance, so keep the certificate with your house documents.
How many window and glazing companies are there in Belfast?
This directory holds 524 active window and glazing businesses across 79 towns in Belfast, all from the Companies House register. Belfast accounts for 66, among the county's busiest. About 38% of Belfast'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.