Sash window draughtproofing - daft question time!

[Geoff Flegg]

I'm looking to draught proof my sashes, using one of the proprietary brush seal systems, whereby you replace the staff and parting beads with ones with brush pile carriers built in + rout a groove in the meeting rail to take the same.

http://www.reddiseals.com looks to be the most cost-effective supplier I can find, as unlike most of the rest they supply components individually rather than just as complete overhaul kits - i.e. you can order what you really need, not what a standard kit provides. If anyone knows any better please speak up!

The daft question is to do with the brush pile weatherstripping that goes in the carrier. Take for instance the staff bead, obviously it's only on the bottom half of the window that the weather stripping is actually required, i.e. to seal when the window is closed. But if you don't put the brush pile all the way up, do you get problems with it moving or getting dragged out of the carrier as the sash opens and closes? Same thing applies to the parting bead, but this time it's only the top half on the window that really needs the brush pile, but do you have to run it all the way down?

I hope that's clear!

 

[biffvernon]

Good question. I get stuff from reddiseals. I've never used the brush pile in a carrier, just the simple brush pile with a sticky back. Have you thought about putting the brush pile on the sash, rather than on the bead?

 

[Geoff Flegg]

Could do I suppose - although the websites I've seen show them on the beads:-

http://www.sashwindowspecialist.com/draughtseals.html

http://www.diysashwindow.co.uk/Sash%20Sizes.htm

There must be some reason for it - if you just used the sticky-back stuff on the sash, would it not eventually come away?

Anyone fitted or had a company in to fit any of these kits?

 

[Mark]

thanks - I hadnt come across that site.

Are their pulleys any good - the ones I have found elsewhere are useless.

 

[biffvernon]

I think Mighton are the biggest supplier of decent window stuff. They sell brass pulley's with ball bearings and stainless steel ones that stay shiny forever.

Oh, and I forgot, the other firm that does, as they say, "all you need for timber sash and casement windows", even lead weights, is Reddiseals

 

[Mark]

Great - Looks like I'm sorted for doing the next sash.

thanks Biff

 

[Geoff Flegg]

C'mon guys, surely *someone* on here has draughtproofed their sash windows?? Or had someone in to do them?

Maybe it's the way I phrased it - what I'd like to know is if your sashes have been draughtproofed with brush seals, and these are on the staff bead, do they go all the way top to bottom or do they just go on the bottom section where the window sits when it's closed?

The staff bead is the timber moulding that runs round the inside edge of the box - i.e. the strip of timber round the inside edge of the window that you'd have to remove if you wanted to take the bottom sash out.

Or has anyone successfully draughtproofed another way? Biff suggested fitting the brush seals to the sashes, which is intriguing.

Last winter I draughtproofed the worst windows with loo paper, shoved in place with a wooden kitchen spatula. Quality workmanship, eh? :wink:

 

[Nemesis]

I've spent several decades with the loo paper approach and found it perfectly fine!

 

[Mark]

last time I painted I stuck some of the fluffy roll stuff around the sides of the sash. so it sits between the sash and the side of the frame and isnt visible.

I didnt want something really obvious on the frame.

Its better than it was but still not brilliant.

 

[Moneypit]

C'mon guys, surely *someone* on here has draughtproofed their sash windows?? ........ Biff suggested fitting the brush seals to the sashes, which is intriguing.

Yes, I have .... and I'm doing it the way Biff mentions.

A previous post refers to Mighton Products who do a big range of fittings. So far I have bought pulleys (brass and chrome) which seem well made although the sea spray onto the front of the house has already eaten the lacquer on the brass and started to rust the steel parts!! I have also bought their brush seal, brush seal holding strip and an expensive router bit to machine the groove.

The idea of putting brush seals onto the hidden edges of the sash appealed to me. Other people have tried the parting bead seal where the bead has a flexible strip running the whole length but to my mind even that would look out of place.

The basic technique is to rout a 'T' shaped slot (or two) along the whole side of the sash. The plastic brush strip holder is then pressed into this so that it sits flush with the surface. The brush strip, which is short fibres sandwiched between two plastic film leaves, is slid into the holder. Sounds great doesn't it. I'm finding it to be a bit of a fine art to achieve and i'll do my best to list the problems for you. I will say that I have found it to work very well. We live facing the Irish Sea on the west coast of Cumbria. It's VERY windy a lot of the time. Trees won't grow higher than the fences that are still standing!

Problem 1
For this method to work well requires that the available side to side movement of the sash in the frame is regular over the height of the window and, most importantly, quite small - about 5mm total. This is so that the brushes when compressed on one side don't leave a gap on the other. So far I have found that I have, with some windows, had to build up the side of the sash to reduce the gap.

Problem 2
The 'T' slot is 5mm wide and is cut at 90 deg to the axis of the router, so the router runs on the face of the sash. A fair amount of setting up is required and the control of the router (which is large because it has to have a 1/2" collet for the bit) for the delicacy of the T slot is not for the faint hearted.

Problem 3
The 'T' slot runs the full height of the sash and therefore runs along side (along both sides if two are put in) the groove for the sash cord. Depending on the thickness of your frame this doesn't leave much material either side of the T slot, either between it and the outer edge of the sash, or it and the edge of the cord groove. The important one is the outer edge because that then becomes vulnerable to being split off. This is especially true if you, like me, have had to build it up by adding on a thin strip of wood. The air was blue that night!

Problem 4
The strip moves freely in the strip. This is great for getting it in, but if left that way will obviously be forced out by the movement of the sash when being opened. A couple of ways to prevent this would be to glue the strip in or stop the 'T' slot short of top and bottom. Stopping it short will leave that bit still available for the howling gales to use but hey you need some ventilation and the sash won't be rattling.

Problem 5
On the subject of gaps being left there will always be a route through from the bottom of the window, up the middle of the sash edge and out past the cord in its groove. This can probably be prevented by positioning a crushable strip along the underside of the outer edge of the bottom rail.

Sounds too much effort to bother doesn't it? Well, I'm sticking to it for a bit longer. It can only get easier can't it? There is so much pleasure in having windows that glide up and down with the lightest of touches when they had been stuck solid with filler and paint. We have 29 windows so that's 58 sashes, that's at least 116 T slots. So far I have finished one of the windows and it's been a year in the house. I'm 50 now, I worry about holding a router steady when I'm 78.

I have taken some photos of the one that's done and the next one that's only part done. I will post them soon.

 

[biffvernon]

Congratulations. Much better than the simple self adhesive brush pile that I suggested. Mind you, I think with my method you'd stand a fighting chance of getting the whole lot done in a long weekend

 

[Geoff Flegg]

Wow! That's a lot of sashes. And there was I thinking 11 windows was a big job!

Thanks for such a detailed reply - We're on a high spot here in Shropshire, and we're the tallest building around, but as Shropshire isn't noted for it's coastal exposure I'm sure you get a hell of a lot more wind where you are! Good to hear that the draughtproofing works.

The side-to-side movement of the sashes will be a problem - some of mine are quite loose, but the box sides aren't parallel, so packing them out will be awkward at best. Similarly I think on some windows there may not be enough timber to run a router groove alongside the sash cord groove, so the parting bead/staff bead method might be the only way, although your way would undoubtedly look better. You can get 2 sorts of parting bead by the way - one is all plastic, has a flexible flap both sides to run against the sashes, which is I think what you're referring to. The other type is timber as per the original, but has an inbuilt brush strip carrier on one face, which goes against the outer sash. I think it will be a bit more discreet than the all-plastic variety.

I know what you mean about the satisfaction of getting the windows working properly. None of my top sashes work at present, they're all painted shut (they should all work). I got a couple of stuck bottom sashes freed last weekend, really good to get them working again after who knows how many years. The "glide up and down with the lightest of touches " bit appeals - my better half really struggles with some windows, she is doubtful that sashes can ever work that well!

 

[SW]

Hi Geoff,

All my sash windows are draught-proofed with the timber and brush staff/parting beads you mentioned. They are fitted across the bottom of the sash when closed and completely up the sides top to bottom to reduce the chance of pulling the brush out that you mention when you slide the sashes.

There is also a brush routed into the top edge of the bottom sash where it meets the bottom edge of the top sash when fully closed (no idea of the correct name!)

These work very well, look great and I've had no probs in the year since they've been fitted (not by me I hasten to add but it didn't look at all difficult when the guys did it and it)

SW

 

[wobs]

Oo oo a question I can answer. Hurrah!

I've done two sashes on my house (well I only have two sashes left).

I used the brush pile strips that people have mentioned.

As you said, the staff bead has a T groove routed along it. I didn't route it myself, as I bought the kits with everything in it, but the if you fit the staff bead draught proofing all the way along (as you should), it will have no potential problem regarding the brush stuff sliding out. And the window slides fine along it.

The parting bead, as you say, has only half length draught proofing. Now the plastic housing for the strip is set into a routed groove, the brush is effectively housed below the surface, so if it feels the need to slide with the window, it should meet the other parting bead that is solid on that side.

The only potential problem you could have as you say, is if the parting bead isn't in square, the brushes may slide with the window. The locating groove should sort this out, although a few pins should also help keep things hunkydory. I've not had a problem with this, and I'm no skilled craftsman, but its something you just need to be careful of.


As Moneypit says, Mighton do a good range of fittings, but I'm not so keen on their draft proofing by the looks of things. I'm yet to be convinced on their reliablility.

http://www.diysashwindow.co.uk/index.htm
http://www.heritagesashwindow.co.uk/sashwindowsrepairing.htm
http://www.sashwindowspecialist.com/kits.html