1970s windows

The 1970s windows I see on a job were fitted in the decade when double glazing first became something ordinary people bought. A house from this period may still have its original frames, or it may have been glazed once already, so it pays to look at what you actually have before deciding what to replace.

The decade behind 1970s windows

As I remember it, house prices were the big worry of the decade. Prices rose very fast, and mortgages were hard to get, so first-time buyers had a hard time. Do-it-yourself took hold of the country, and people had more time at home for it.

It was also the decade when crude oil prices jumped, and the energy-saving, home insulation and double glazing era began. I can’t give you figures from memory, and I haven’t included any. A glazing firm’s history of the period, Selectaglaze, says energy crises throughout the decade made the heat-saving qualities of glazing a bigger selling point as people tried to conserve heat. It also says the spread of double glazing sent secondary glazing makers into the older, protected buildings.

What your 1970s windows may be

I can’t tell you what is in your house without seeing it, but here are the questions I’d ask on the doorstep:

• Are the frames original? Many houses of this period have had their windows replaced at least once, so what you see may be a later job.
• Is it single glazing, secondary glazing or sealed units? Early double glazing was often a second pane fitted inside the existing window. A sealed unit has the two panes joined as one, with the gap sealed.
• What are the frames made of? Timber, aluminium and early plastic frames were all in use. The material decides what goes wrong and what a repair involves.

Repair or replace

If the glass in a frame has misted, you may only need new units. Our guide to sealed units explains how to tell, and sealed unit replacement shows what it costs. If the frame is worn out, a new window is the better spend. I’d decide by looking at the frame first, not the glass.

What to ask before you order

Ask the installer to state in writing:

• what the new window is made of, and how it opens;
• the glass specification, and the energy rating of the whole window;
• what happens to the old frames and how the finish round the opening is done;
• who certifies the work. The Planning Portal explains that building regulations apply to all replacement glazing.

The guide price for a single replacement window is for a standard casement. Put any quote through our quote checker. For the decades either side, see 1960s windows and 1980s windows, and the your windows hub for the rest.