Weep holes in wooden sash windows?

[LeeL82]

I've got a situation where my windows get an awful lot of condensation that pools in the window, our windows also are in a peculiar shape and the water pools in the bottom section with is like a V that slopes backwards in towards the glass so when i wake up of a morning there.s a little pond in the windows. Humidity wise, the house sits around 50/55RH although at the moment its sitting at 60RH.

Would it be practical to drill a tiny hole through the window and let this water run outwards or would this eventually rot through the wood of the window and cause a bigger problem?

I can upload a picture if required and any ideas would be great,

Thanks in advance.

 

[Gothichome]

Hello Lee, it is never a good idea to expose wood to water, drilling an escape hole in my opinion is just asking for rot. Several questions, I will assume this V type pocket is interior side ( you suggest letting it out) Is it on the sash or the sill? Any chance you have sealed to home up to tight and you have very little fresh air infiltration?
Is it only one window, one room, or the whole home you are experiencing this condensation? Maybe a dehumidifier is in order.
It is common hear in Canada that folks think they are doing them selves a great service in making their old home tight, but often it leads to other issues if they don’t compensate for fresh air movement with mechanical means.
I think a picture might be in order.
Ron

 

[LeeL82]

Hiya gothic,

Cheers for the reply, its definitely not sealed, its single glazed sash and case windows, the water sits on the sill as you can see from the attached, when we moved in the old sills were also rotted so we replaced with new ones, i can see why they were so rotted though. The water pools at the bottom and the sills slope in towards the window, this is our two littles one bedroom aged 4 & 1. I live in scotland where the temperature the last few mornings has caused frosty grass and windows on the cars. the first picture is the morning sunrise, the second picture is the puddles, these often overflow and land on the big inner sill.

 

[Flyfisher]

I agree that simply filling a drain hole would likely lead to rot. However, this risk could probably be mitigated by inserting some sort of small plastic tubing. If properly sealed somehow that should prevent the water coming into contact with the wood. Having said that, my preference would be to address the condensation and the whole ventilation vs draught-roofing issue. Our approach is to open our bedroom window slightly just before bedtime, which makes a huge difference to the condensation. Less energy-efficient I suppose but it also ‘feels’ more healthy - might just be psychological (though that’s not such a bad thing anyway). Whole-house ventilation with heat exchange etc (basically air-con) is the high-tech way to solve the problem but seems overkill in a domestic setting, especially compared with just opening a window slightly.

 

[LeeL82]

I agree that simply filling a drain hole would likely lead to rot. However, this risk could probably be mitigated by inserting some sort of small plastic tubing. If properly sealed somehow that should prevent the water coming into contact with the wood. Having said that, my preference would be to address the condensation and the whole ventilation vs draught-roofing issue. Our approach is to open our bedroom window slightly just before bedtime, which makes a huge difference to the condensation. Less energy-efficient I suppose but it also ‘feels’ more healthy - might just be psychological (though that’s not such a bad thing anyway). Whole-house ventilation with heat exchange etc (basically air-con) is the high-tech way to solve the problem but seems overkill in a domestic setting, especially compared with just opening a window slightly.

I'll give that a shot actually, it's worth a shot. Whole house aircon does seem a tad overkill and probably seriously expensive, I've thought about a PIV unit but not sure if this would help alot.

 

[Feltwell]

Secondary glazing would cut the condensation down massively.

 

[CliffordPope]

Secondary glazing would cut the condensation down massively.

It would cut it down massively on the window, but it would surely still go somewhere?
It condenses on the glass because that is the coldest surface. What's the next coldest surface- solid floor, behind a cupboard, outer wall?
Double-glazing is for warmth and energy-saving - worth doing, but it won't reduce total condensation.
In my experience a dehumidifier is the only answer. Put it on a timer so it runs on cheaper night-time electricity, and over-ride it for exeptional day-time dampness.
If necessary have two, upstairs and down.

 

[Feltwell]

Secondary glazing would cut the condensation down massively.

It would cut it down massively on the window, but it would surely still go somewhere?

Yes, but the effect will be less - depends how much warmer the next warmest surface is as to how much of that airborne moisture will condense on it. I do take your point though, but secondary glazing can have quite an effect and I've not seen the moisture appear elsewhere.

Here's 2 identical sash windows side by side, one with one without secondary glazing - sorry for blurry image, Photobucket :evil: :-



I've given up on secondary glazing here but only because my windows just really don't suit it, I just can't get a system that looks OK and is practical to use when you do want to open the window. But, if I could, I'd fit it like a shot. I stay in a lot of hotels for work and tend to pick on older buildings where possible, they often have it fitted and it works very well - especially on windows sat in an internal recess.

 

[88v8]

That's awfully damp. Is there a functioning fireplace in the room, or any other ventilation?

That said, our single glazed kitchen windows run with water. And I recall back home - as I think of it - in the 60s there was so much condensation on my bedroom windows that I created a network of plasticine channels to collect it. Back then, it's just how it was.

Anyway, 60% RH isn't overly damp. But a dehumidifier would make a big difference. We have two Ebac 2650 that we run 24/7 in the winter.

And as said, secondary glazing will also help. But Clifford is right, it can just move the problem elsewhere, because the underlying problem is too much damp air and not enough ventilation.
One way to get draught-free ventilation with double-hung sashes is to make a board about 2" deep and the width of the sash, open the top sash and put the board in there. Now you have ventilation between the meet rails, but no draught. If you combine the board with sash stops to prevent the windows being opened further, they can be left 'ajar' like this, and still be secure.
https://www.locktrader.co.uk/Perkins-and-Powell-P268-A-Sash-Window-Stop-Brass.html

No, I wouldn't drill a drain hole. It will rot the wood, and let bugs in.

Ivor