Ivison Interiors Ltd

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 (TS17 9RE) directly on the FENSA or Certass website before booking, and ask to see the certificate number.

The registered company name, registered office address, Companies House number and incorporation date, all taken from the public Companies House register. It does not include reviews, prices, staff details, or confirmation that the company is currently trading.

Repair makes sense for a failed seal (misted double glazing), a worn handle or hinge, or a damaged lock on an otherwise sound frame — usually a straightforward swap. Replacement is the better value once frames are warped, draughty, rotten (on timber) or past roughly 20 to 25 years old, or when several units across the house have failed. Ask the installer to price both where it's borderline.

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.

This directory holds 406 active window and glazing businesses across 47 towns in County Durham, all from the Companies House register. Stockton-on-tees accounts for 36, among the county's busiest. About 42% of County Durham'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.