How can I seal this sash window?

Hi! My sash window has quite a bad draught coming in through the gap between the top and bottom window.

2026-01-2814.46.27438557974151358096.jpg

Both to keep bugs out at night and to keep out the draught. Its the only window in the room, so I'd rather keep the ability to open it.

I've considered foam stripping, but I'm concerned that opening the window would tear it away, and I'm not sure how I'd apply it.

Alternatively, I've considered applying a door seal to the window, that can be pushed out of the way when it slides up.

I've not done much home improvement before but I've just moved into what will hopefully be my home for the next few years at least, so I want to make it as nice to live in as I can. Thanks!

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EricL

Hello @nukeboy1313

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about sealing your sash window.

I was going to actually suggest using a Moroday MDS2B Self-Adhesive Black Econo Door-Seal on the section of your window that moves. This will prevent it from getting pulled off and stripped off. I propose drilling small pilot holes on the door seal body so that you can screw the seal onto your timber window frame, it can be cut to size so that it avoids the locking mechanism of your window. My best advice is to make sure that the window frame is clean and free of debris before attaching the door seal.

Let me call on our experienced members @Dave-1, @Nailbag and @JoeAzza for their recommendations.

If you need further assistance, please let us know.

Eric

Dave-1

Good Evening @nukeboy1313

I was thinking of Moroday 6 x 7mm x 5m Black MWS8 Self-Adhesive Brush Seal stuck to one side of the gap between the windows. (the one easiest to reach really) If its too tight a space for it to fit in then you could mount a piece of timber trim horizontal on top of the bottom window a little offset from the edge and glue that to the timber (so no chance of cracking the glass with screws) and then paint and stick that weather strip to the side so it covers the gap.

Dave

Nailbag

Hi @nukeboy1313

I have had to seal a few old sash windows in my time and due to their nature of sliding up and down unevenly, anything your place in-between will pull away every time you move the frames. That Moroday MDS2B Self-Adhesive Black Econo Door-Seal @EricL suggested will work great. You will just need to trim it to clear the latch.

Nailbag

nukeboy1313

Thanks all! Upon reviewing, it looks like the MDS2B isn't sold in new zealand- apologies, I didnt spot that this was an Australian forum. I think the MDS2 and 2A are too small/big respectively, but will need to do some measuring.

The outer and upper half of the window needs repainting, it looks like, so in the meantime I will be using the MWS8 anchored to the inner and lower half of the sash window.

Jason

Sorry @nukeboy1313, we're definately a community for Kiwis as well as Aussies. Let me ask one of the team to suggest some alternatives for you.

Jason

EricL

Hello @nukeboy1313

The NZ equivalent that you can use is the Moroday Bronze MDS3 Compact Door Seal. This is actually a better alternative as it has mounting holes and you can use small screws to mount it to your window frame. Should you decide to get a different colour my best advice is to make sure that the seal is made of EPDM rubber and not the brush type seal.

If you need further assistance, please let us know.

Eric

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