Secondary double glazing

[Manateedugong]

Our Edwardian house has its original Windows which look lovely but it's noisy as we are on a busy main road.
Has anyone got experience of secondary double glazing and if so could you give me an idea of costs and how well it works for noise reduction.
We would want it on 2 large bay windows downstairs and French doors which go onto balconies upstairs (I assume this will be more complicated).
Also, can anyone recommend any companies?

[MightyMeerkat]

I can't recommend anyone but I too would be interested in the responses. I'm in the process of buying an Edwardian house with single glazed wooden windows and everyone I've spoken thinks I'm nut! Aside from the noise, do you find they make the house cold and cause lots of condensation? I'm starting to worry that I am going to need to replace them not long after moving in

[PigletJohn]

old, single-glazed windows are unlikely to cause condensation, because they are often draughty, which provides ventilation to exchange the humid internal air with drier outdoor air.

You might see condensation on the glass, because it is cold, but this would otherwise be forming on the walls, which may be worse.

Secondary glazing, well-fitted, provides better noise insulation than sealed dg panes. It will be better if you use a thicker glass than in the original windows. The thermal insulation is not quite as good, but will make a substantial improvement over single glazing.

If you like net curtains, they can make secondary glazing very difficult to see.

If you still have original windows, it is worth having them overhauled, any rot repaired, properly painted, draughtstripped, locks fitted, and any gaps between windowframe and walls repaired. Old putty can be replaced by modern glazing compound and tape, which lasts longer, and does not harden, crack and fall out.

[PigletJohn]

p.s.

p.s.

If your Edwardian house has casement windows (hinged, like a door) you can have them reglazed with sealed dg units. These units are always made to order, so unusual sizes will not matter. They are heavier, so this is the time to have new wooden casements made by a local joiner company, if the old ones are in poor repair. Keep the handles and stays, if they are original.

You can't add dg units to vertical sliding sashes; because they are too thick and will throw the balance out.