Replacing old double glazing in Horsham's 1970s and 1980s houses

The urban district had 26,446 people in 1971, and the town with Roffey and Broadbridge Heath had 38,565 by 1981. Southwater, just to the south, had about 1,600 houses by 1982. That puts a lot of local houses at the same stage at once: their first double glazing, fitted new or added in the 1980s, is reaching the end of its life.

Signs the frames are finished

• Mist or droplets between the panes. The seal has gone and the gas has escaped. A new sealed unit can fix one pane, but if several are going, the frames are usually the same age.
• Hinges that drop or will not hold the window shut. Friction hinges can be replaced, but on old frames the screws often pull out of worn reinforcing.
• White uPVC that has turned yellow or chalky. Early profiles did this more than current ones.
• Draughts at the corners. Welds and gaskets shrink over decades.

When repair is worth it

If the frames are sound and only one or two units have misted, replacing those units is cheaper than new windows. Many glaziers in the Horsham area do this. It is worth asking for, and an honest surveyor will say so if it applies.

What is different this time

When the 1980s windows went in, the rules were looser. New replacement windows now have to meet the heat-loss standard in Part L of the Building Regulations. Upstairs bedrooms need an escape window of a minimum opening size. Trickle vents are now expected in most rooms when windows are replaced. A FENSA-registered installer self-certifies all of this and you receive a certificate, which a buyer's solicitor will ask for when you sell.

What to replace them with

On most 1970s and 1980s houses the honest replacement is a chamfered uPVC casement, in white to match the street or in grey for a change of look. Wide picture windows suit slimline aluminium. See the house era guide for your period and the Southwater example for a whole-house figure.