Kpo Carpentry Ltd

Not much, but not none. Wipe the frames a few times a year, lubricate hinges and locks annually, and keep the drainage channels along the bottom of the frame clear so water can't pool and find its way inside. There is no statutory annual service like a boiler needs.

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.

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.

This directory holds 456 active window and glazing businesses across 61 towns in Hertfordshire, all from the Companies House register. Watford accounts for 56, among the county's busiest. About 31% of Hertfordshire'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.