John Simpson (carlisle) Limited

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 (CA2 5XP) directly on the FENSA or Certass website before booking, and ask to see the certificate number.

Use the "Get Free Quotes" form on this page. Your job details go to FENSA or Certass registered installers covering the CA postcode area, who contact you directly. Carlisle has 76 registered window and glazing businesses in this directory, though the installers who quote are not necessarily among them. It is free and there is no obligation.

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.

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.

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.