Double Glazing for Sash Windows

[Cherrytree67]

I have just moved into a Victorian flat with sash windows which need some care (big gap, not opening etc.). I am undecided whether I should just go for draught-proofing or have them double-glazed with Slimlite. Has anyone any experience with Slimlite double-glazing? Thank you very much in advance.

no, but it appears to be a system for removing the existing glass from the sashes and putting thin sealed glazing units instead.

Not keen. Old vertical sashes tend to suffer from draughts and gaps, and it is expensive to have them refurbished. You will need to change the sash weights if you change the glass. I doubt that changing the glass will make a big difference, except to your bank balance.

I think you will get better results from secondary glazing, which will block the draughts, cut heat loss, and reduce sound transmision, and can also improve security.

Vertical sliding secondary glazing is not often seen. I don't know a current supplier.

In older houses it can be invisible if you have net curtains, and inconspicuous from outside if you have thin sections.

Secondary glazing is better.
If the sash windows stick try running a white wax household candle between the runners top and bottom ,this will help the window slide.

I have several slimlites. Original and draft proofed so have good knowledge of them all.

Slimlite is warmer than draft proofed single for sure. Makes hardly any difference sound wise. Draft proofing on its own makes a big difference in the feel of the room due to no cold breezes but the heat still leaks out of the glass.

Secondary would be far better for both.

Issue you’ll have retrofitting slimlite is weights and your style of windows. Some windows can’t take the weight or thickness of the glass.
Depending on the frame thickness or Georgian bars you may have to cut out the bars and have stick on bars instead.
Also if your windows have small weight pockets you may have to accept your windows won’t stay open without a wedge.

Also slimlite can fail early if used in a putty faced window.

But i hear “Pilkington spacia” glass solves all of these problems and is better for sound proofing but has a metal circle on the pane which fuses the glass together.

Thank you so much to everyone. Much appreciated.

The issue I have got is that I already paid for the Slimlite. But when I got them delivered this week (for installation in a few weeks' time), I only then realized how very heavy they are and also darker than my single glazed windows. I started to have doubts whether I made the right decision.

From what everyone is saying, I think I will just have my window draught-proofed and make a loss on the Slimlite. Phew ... Silly me! I should have done more research beforehand.

Thank you to everyone.