Dovetail Joinery & Building Services 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 (DL2 3NH) directly on the FENSA or Certass website before booking, and ask to see the certificate number.

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.

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.

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.