Sealing secondary glazing units

[David Neale]

My house is a 1900-ish terrace with most of the original sash windows. A couple of years ago these were refurbished and draughtproofed and so are all in good condition and offer reasonable draught and sound insulation.

However, because of sporadic noise from a nearby factory I've decided to install secondary glazing units in the front bedroom (Easyglaze vertical sliding DIY kits, with glass separately sourced locally). The inside of the sashes is almost flush with the wall, so these will have to be surface mounted on the wooden sash boxes and the gap will be about 40mm, which is not ideal but the best that can be achieved.

To achieve optimal sound insulation I guess it would be a good idea to seal the secondary glazing units to the sash boxes. And here's the question...for best sound insulation how should this be done? I'm thinking of some kind of suitable thin tape, or maybe using a flexible filler.

Any suggestions?

TIA,

Dave.

[Lobster]

Doesn't the system include the wherewithall/instructions on how to do this?

However, also, isn't Easyglaze intended for plastic sheeting rather than glass? Not sure how significant the difference is, but glass is a hell of a lot heavier than the equivalent plastic - may not be safe?

David

[Phil Anthropist]

A bead of silicone sealant?

[David Neale]

Thanks for the advice. I checked with the supplier before purchase, and they are suitable for glass up to 4mm thickness (although it seems to be claimed that the latest polycarbonate sheets don't scratch easily or go yellow or hazy I would still prefer to use real glass). As the windows are just over 800mm from the floor I can use standard glass with no question, although if anyone knows of any 4mm glass with superior acoustic properties I'd be interested to hear (think acoustic glass is typically thicker).

[David Neale]

Thanks for the suggestion, Phil - that's probably what I'll go with unless anyone knows of an alternative with better sound insulation properties. BTW - anyone had experience with Easyglaze sliding units? They certainly seem a reasonably cheap solution (works out at about £170 per window including glass) and have the advantage from my point of view that they only need to be closed at night so hopefully shouldn't cause any condensation problems. If I hear nothing back I'll let the group know in due course how I got on...

[Chris Bacon]

Have you a URL for "Easyglaze"? Also, I'm not sure what "The inside of the sashes is almost flush with the wall" means. Windows in a corner?

[David Neale]

These units are from DIY Plastics, which seems to be part of the same group as Protech, at the following URL:

I meant was that there is no internal window reveal (in common with many Victorian houses the reveal is on the outside only) - the window is flush with the interior wall (so mounting of the secondary glazing in the window reveal is not possible). Hope that's clearer!

The units arrived today in one long parcel, hope to fit them at the weekend.

[David Neale]

Well well! This may be some good news for DIYers....

Just opened the box and it contains kits from a company caled Linkline. After some Googling, visited the site at

which explains that they are the successors to the much lamented Polycell kits of old, made to the original Polycell design!

Could have stumbled on a useful discovery - I'l let you know how I get on....

[Chris Bacon]

I'm very interested in 2y. glazing for sash windows (I need some for my own house). Could you, with these units, run a batten (or architrave, perhaps one to your own spec. machined at Jewson or wherever) around your sash window, fastened to the wall itself, replacing any cill with a wider one, and fix the 2y. glazing onto that? You could then leave the entire sash window, and architrave for that window, completely untouched, and visible through the

2y. glazing. That would have a positive benefit of eliminating draughts coming in/going out from "behind the architrave", as well as improving the noise reduction, as the whole 2y. glazing would be independant of the sash window, which might be liable to vibrate as a whole otherwise. So, in X-section (adjust your news reader to a fixed-width font), you'd have (plan, section):

##################### ##################### ##################### outside ##################### ################-------- sash box ################ | ################ |------------------- top sash ################ |------------------- bottom sash ################________| @@@@|_a |_a = exstg. architrave !@@@#-------------2y. glazing-----

/ \ Possible \ 2y. glazing attached to batten @@@@ moulding on \ !@@@ hard up against back of exstg. architrave batten at "!"

If the batten attached to the wall was of (say) 3x2, with or without machining of a decorative moulding, the curtain would cover it and the 2y. glazing would be concealed to boot!

What do you think?

[Chris Bacon]

...to fit laminated glass, 4.4mm or 6.4mm. Will it fit?

[David Neale]

Should be no problem, just (of course) allow for the extra dimensions when ordering. As a guide, the windows are about 40mm deep. In fact when surface fitting the instructions stipulate that you need a secure sill or batten of at least 38x38mm at the bottom of the window to support the unit.

[David Neale]

Strictly speaking, no. But these units are pure UPVC (no aluminium frames) and are therefore fairly flexible so it *might* just be possible to squeeze

4.4mm glass >>>>David Neale wrote:

[David Neale]

Hi everyone,

Finished installing both windows in the front bedroom yesterday and the result is quite satisfactory. I used plain 4mm glass, which is actually recommended as the preferred choice in the instructions supplied with the kits, and the result looks fine and works well. Sound insulation is fairly good but probably not as good as using fixed secondary glazing - in particular, the higher frequencies seem to have been attenuated considerably. Because the secondary glazing is surface mounted on the sash box I used rubber double glazing tape inside the side rails to cover up the pre-drilled holes (with the backing left on so that the edge of the glazing doesn't stick when inserting or removing panes) and decorating caulk to seal the inside edges of the rails to the sash box. In total the job took about

12 hours for two windows including getting the glass from a local glazier.

In case anyone's interested in seeing the result, I've posted some pictures... Before:

showing ratchet track and catch: