Secondary Glazing

[MatthewC]

I'll start a new thread to reply to DJH from a plastering thread:

Sorry to go off topic here but I've just read the section of your blog dealing with secondary glazing Matthew. How are you getting on with the acrylic now it's in position. Are you getting condensation at all, and if you are, is it on the window glass or the acrylic?
I'm also guessing that in order to fix the sheet to the window frame you've removed the window furniture? I'm contemplating doing the same thing here. Do you have any close up pictures please?

I think the acrylic SG is great (so far); it has reduced draughts, increased the temperature and we don't have any condensation (yet) which could be because of the considerable amount of ventilation through the sash windows! Here's a photo of one of the windows (note builders yard in background):
And here's another window which is so large that I had to use two pieces of acrylic. I made the grooved wooden support that crosses in line with the join of the sashes so it can't be seen from outside (NB window refurbishment is waiting for the next time we have a summer):As you can see, the windows (and the staff beads - just) are nicely recessed thus providing a simple base for the acrylic with no need to remove any window furniture. The only trick is to not screw too deep. Finally a detailed one showing the edge strip and the nylon clips:More details on my blog (see blue spot on the right).

Matthew

 

[Moo]

That looks exactly like what we did in Norwich, right down to the big window that needed two separate panes of perspex. Not at all expensive, and easy to disassemble when the weather warmed up.

 

[DJH]

Thanks for that Matthew. You've convinced me to go down this route with acrylic. We suffer badly with condensation on the windows and as you've trail blazed with little or no condensation I'm more comfortable about the idea.

Here's the view from our kitchen window. The top of the mountains is covered by cloud and there's snow up there..



so you can see why we don't want the view obscured by condensation.

Doug

 

[Moo]

That reminds me of another advantage - it's so easy to clean off any nasties that manage to settle between the glass and the perspex/acrylic/plastic stuff.

 

[JoceAndChris]

That's a beautiful view you've got there Doug.

Love the secondary glazing, must must must get on with this.

 

[DJH]

Here's a view through my window with no cloud on the mountain just snow I'ts bitter cold here today as it always is when there's snow up there as the wind blows down across it towards us. We only have a small amount of condensation on the windows this morning for some reason.........



Doug

 

[tobydog]

Doug - when the air is colder it can be drier which helps in the reduction in condensation. Add wind to that and the removal of moist air from your house is accelerated. I love cold windy days around our house at this time of year because we too get rather soggy except for the fact that the timber frame walls are rather thin and we really feel the wind chill.

 

[DJH]

That explains it Tobydog. I'm very keen to get on with doing the two North facing windows ( this is one of them) with acrylic. The new extension has double glazed units in them. The windows in there were off the shelf Cottage Style from Jewsons.. :shock:

 

[plasticpigeon]

Has anyone fixed acrylic/polycarbonate sheets within the mouldings in the sashes? I'm thinking this could be visually less intrusive and still allow the windows to open. It wouldn't stop draughts, but on the one window I've restored with with draughtproof beading, the only significant draughts are at the meeting rails. this is done commercially by the company in the link.

http://www.conservationglazing.co.uk/index.htm

 

[88v8]

Acrylic? No although when our new sashes were first installed in our previous house in 1981, I designed them to be double-glazed with glass & tape. Eventually, they misted up of course, and uv+heat degraded the varnish (mahogony sashes) betwixt inner & outer pane. The more sun, the faster the degredation; the one most shaded endured for over 25 years, although it was well misted by then.

A couple of problems with this acrylic wheeze, other than the 'precision' sealant huh...
- the weight is significant. Even a pound aded to the top sash will tend to make it drift downwards, and make the bottom sash heavy and disinclined to remain raised.
- a vacuum will be created between the panes, inevitably it will leak air, misting... It's not only the internal seal that has to resist vacuum, it's the external putty bead. Larger pane, more vacuum.
- the paint between the panes will degrade, how ya gonna repaint it.

Best way to save heat, cut draughts - well-fitted curtains... not hanging over the radiators.

Condensation, ah, well, that's a different matter. Funny to see that plastic channel secondary glazing with the plastic clips; we inherited that in our previous house, probably of 60s vintage. Yellowed channel, brittle clips, glass. Never got round to removing it, well we had net curtains so you couldn't really see the glazing and the window looked out onto the road so we had no incentive to look through it. Winter-only systems are OK so long as you have somewhere to put them in the summer, somewhere where the glass won't get broke or the acrylic scratched.

Ivor

 

[Bayliss]

Just completed the exact same job in our cottage, same materials/clips/draught excluder. Simple to install and a huge difference in terms of warmth. However, I remain mindful of the need for some draughts, to this end we have left the gale force wind coming in under the front door blowing our door curtain like a viking sail. :shock:

 

[Feltwell]

I'm more of a fan of the magnetic systems than edging strips & clips - I suspect the edging strips will end up not looking so good in the end if they are the clear type, they'll trap dirt.

The disadvantage of the way I've done it is that you need to store the sheets in summer, the advantage is that is quite a discreet system - especially what is is left behind in summer - and it will be more effective that putting acrylic on the sashes themselves, as the gaps round the sashes will also be covered.

See these old threads:-

http://periodproperty.co.uk/forum/viewtopic.php?f=1&t=11602&p=149449&hilit=secondary#p149449

http://periodproperty.co.uk/forum/viewtopic.php?f=1&t=11602&p=149449&hilit=secondary#p149449

 

[DJH]

I like your way of doing it Feltwell. It's much less visually intrusive than the clip system and I do particularly like being able to paint the steel tape so that it blends in with the window frame. Now I have to source it over here. Sometimes UK suppliers think that Ireland is the other side of the world! You can hear the sharp intake of breath as you begin to say where you are. :roll:

Doug. along way away in Tipperary.

 

[Feltwell]

I like your way of doing it Feltwell. It's much less visually intrusive than the clip system and I do particularly like being able to paint the steel tape so that it blends in with the window frame.

And what's more Doug, if some numpty had managed to post 2 different links rather than posting the same one twice, you'd have seen how unobtrusive the painted steel tape is. :roll:

http://periodproperty.co.uk/forum/viewtopic.php?f=1&t=12857&p=174313&hilit=horrible+yellow#p174313

And it is indeed a long way to tickle Mary, as the old song goes.

 

[tycarregydwr]

Oh I really like the look of the magnetic tape approach. I think this may be the way forward for our two remaining original sashes! (one currently has aluminium secondary glazing fitted which is very ugly and still a bit draughty, and in any case needs to come off so we can restore the window) and the other has nothing and is above the bathtub - brrrrrrrr.

 

[DJH]

Do you recall where you got the tape and magnetic strip Feltwell :?:

Found loads on e-bay since I posed the question and this one in particular which, I notice, is two separate strips so I suppose they are opposite poles or they wouldn't stick!

http://www.ebay.co.uk/itm/390492016413?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2648

 

[Feltwell]

'twas this one:-

http://www.magnetic.co.uk/ecom-prodshow/magnetic-diy-secondary-glazing-kit.html

 

[DJH]

Thanks. That's definitely the one as the backing adhesive strip is white and will be unnoticeable when the acrylic sheet is in place. I'm of to place an order.

Doug about to tickle Mary as the song goes :lol: