Imagine you’ve been called in to specify a set of replacement windows, but your customer’s house is located in a conservation area. Is it still possible to quote them for standard uPVC double glazing?

The lines are hazy. Sometimes it’s ok to install uPVC windows in heritage houses, many times it’s not. Here’s a guide to the legalities of upgrading windows in period properties.

Limitations And Considerations When Installing In Conservation Areas

Conservation areas protect the history and architecture of a period property by restricting the alterations that can be made. English Heritage says that windows in traditional houses “should not generally be altered in their proportions or details”, because they add to the character of the home.

To get the go ahead for replacement windows in conservation areas, new windows must meet certain requirements. Permitted windows vary according to a council’s specifications. Exact replicas of the originals are almost certain to pass, and more often than not, these are timber sash windows.

Common requirements for replacement sash windows include:

  • Same configurations (e.g. same depth of bottom rail)
  • Same operating mechanism (e.g. sash weights or spiral spring balances)
  • Putty for single glazed panes or beading for slimline double glazing
  • Exact match of glazing bar style and sash horns to originals

Standard uPVC windows are not usually permitted to replace traditional timber sash windows in conservation areas. However, developments in the industry mean that slim uPVC double glazed windows are also accepted.

Rights And Responsibilities For Window Installations In Conservation Areas

It is the homeowner’s duty to make sure they seek consent for their home improvements. If the product is not apt for conservation areas, he or she will have to foot the bill for reinstating windows that do meet the requirements.

It is not the installer’s duty to inform consumers of their responsibilities. But it’s worth noting that selling an unsuitable product at the expense of the consumer will bring a lot of negative reviews and is not worth risking your reputation for.

With older properties that aren’t bound by permitted development rights, homeowners are free to choose whichever windows they like. Most owners of heritage homes want a sympathetic window replacement that offers all modern benefits. Offer your customers exact replicas of their vertical sliders with slimline double glazing, for a draught-free and energy efficient window.

Bespoke Timber Windows By Wessex Restoration

If you don’t offer timber windows as a part of your range, then you may be missing out on a whole sector of the replacement window market. Restoration projects are on the increase, and for a product as durable as a timber window, homeowners are willing to invest in the best.

At Wessex, our highly skilled team of joiners have many years’ experience manufacturing timber products in our dedicated workshop near Bristol. We specialise in creating bespoke sash windows, but we also fabricate timber doors, panelling, cills, architraves, skirting boards and other joinery products.

Visit our website: or call us on 01275 810322 for information about how we help installers offer every customer a tailored solution for their home.

This post has kindly been provided by the marketing team at Purplex.