Fitting a Trickle Vent in a Tricky Place!

19 Dec 2010
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United Kingdom
Hi all,

I've been doing my research over the last few days with the view of fitting a trickle vent to my bedroom window to avoid condensation and ventilation issues.

Hopefully this is a quick question but as you can see from the picture below, there is not enough room to fit the trickle vent into the frame, above the window panel (which opens and shuts) so I just need to know if I can fit the trickle vent into the actual window frame that moves? There is enough room to do this on both sides, just that I was expecting to fit it into the outer frame rather than the window frame itself.

Thanks a lot,
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Can you not leave the window open occasionally on the night vent lock?
Im not a big fan of making a big hole in expensive thermally efficient windows unless you have to.

Assuming you can leave it open for security reasons fit the vent through the top of the opening sash. This is where I would normally fit them anyway.

Its a small white window by the looks of it so in theory there should be no steel reinforcing in your way, So a nice easy job.
Oh quick tip, Drill from both sides. If you try to go straight through from one side or the other you will need to keep the drill perfectly level which is tricky. Also large drill bits tend to bit and pull right in so use a small bit first
Amazing thanks Gaz - so fit it to here;

By the way - it's 900mm wide, would you say 800mm vent? It's a standard sized bedroom that needs venting, but there is a bit of mould so definitely want to maximise the potential ventilation. Thx.
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Standard vent size is 400mm but you can fit a larger one if you can find one
Magic, thanks. I shall probably go for a 400mm then and hopefully that will provide enough ventilation. Have had a look down the street and can see no windows with anything wider than 400mm, and no windows with two.

Shall post any other useful info here if there's any findings worth sharing when I get the job done. :mrgreen:
Problem here is, are you getting condensation from humidity inside house or because of cold bridging from a dodgy installation?

If frame has been fitted tight to aperture, then it can make the frame cold and then warmer moist air inside condenses.

As above, trickle vents in energy efficient windows wouldn't be my first choice either and rumour has it in the coming years they may possibly be banned from use anyway because it's a form of uncontrolled ventilation.
Thanks Click, I'll be looking into this as do really want to understand what's going on. It's only just starting to go cold, yet the whole window still steams up overnight. Not sure if that is a giveaway for the cold bridging. I'm not using any heating yet.

At the moment I'm thinking I also need some kind of air-brick to the outside world to create further ventlllation - but again that's me coming into it 'cold' :rolleyes: so plan to do lots of reading up. It's an old victorian house, lower ground floor.

I'll likely install the trickle next week to see what difference it makes and take it from there. Thanks for the advice. :mrgreen:

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