Gapseal Caulk Strip 10m Magnolia Water Resistant

I read somewhere that if you add together the area of all the gaps around a sash window, you have the equivalent of a small pipe blowing cold air directly into your room from outside. Gap seal has worked perfectly to close all the gaps around the window, and the room feels instantly warmer. This is going to save a fortune throughout the colder months. I've previously used the temporary plastic sheeting, but that leaves a persistent residue that is difficult to remove. I've also repainted all my windows so didn't want to ruin the finish with yellowed adhesive. So if you're contemplating the plastic film, try the gap seal instead. I understand what some reviewers are saying about it being difficult to fill smaller gaps, but I got around this by stretching the product as its being applied, making it easy to wedge into the smaller gaps with the included tool. There's a bit of a knack to it. You want to leave at least some small gaps to retain some form of ventilation. Edited: for some of the really small gaps, I just cut the seal down the middle and it fit easily

Good product, does the job but you can’t open the windows after. Takes time to fit and ok to re fit if you take it out and place it later. It got me through the winter months of cold draft victorian windows.

Soft silicone can be pushed into larger gaps ok and seals well. But difficult if gap less than 4mm as doesn't compress very easily and the tool provided just cuts into the foam. A blunt flat head sscrewdriver is slightly more effective but also starts to stab into the foam as gaps get smaller. Removable with no mess as no adhesive. But that does mean the product is not suitable for windows you wish to open and close.

I was looking for a non-permanent solution to use on sash windows to make them more air tight (and keep warmer) through the winter months. This is perfect, it's a spongy tube which you can stretch and push (with the tool provided) into small gaps (of around 7-8mm or less). It gets trickier as gaps get smaller, but by stretching with one hadn't and gradually tucking/pushing in with the tool, it is possible to get down to a couple of millimetres. Not a good solution if you need to keep opening and closing a window, but for my seasonal needs its perfect.

Did exactly as described and solved my wooden sash draught problem. It was easy to apply and the enclosed tool was invaluable. Highly recommended!

Great product for situations in which you can't use adhesive seals or other permanent solutions. It did take me a while to use on my sash windows, I only lined the bottom of them and not the sides but some bits had larger gaps than others so some bits were a slight struggle to squeeze it in - thank goodness for the included tool, perfect for the task - whereas others, the gap required me to go back the next day and put a second and in some areas third row of this. It did work, more or less... I definitely didn't feel as cold in the property the next night, though I do still feel some cold air coming in, but that may be down to those particular windows, to be fair. The only real niggle is that I'm well aware that I can't open the windows ever, without this stuff falling to the ground below. That's a trade off I will live with this winter but I can easily imagine needing to buy this again in the not too distant future. One pack sealed up two large windows for me, though as I say, some bits needed multiple layers. So it's not a bad investment but if you own the property it's probably more chat effective to use an adhesive style, as a more medium term solution.

great stuff, slightly too big for some of the gaps in my sash windows, so have to cut and mix and match with thinner versions ... but really stopped the rattling. the plastic tool that comes with it has one disadvantage in that with sharpish bits at both ends its not always easy to hold and apply the right pressure to insert the seal ... but i improvised. as it renders the window unopenable, im not sure yet whether we can extract the seal in one piece re apply next year. Great product for static sash, but not a complete solution perhaps ... but hoorah, no draughts

Unless the gaps you are trying to fill are on the upper end of what this product claims to be suitable for, it is extremely difficult to install and push into the gap. The supplied tool is completely inadequate and does not allow you to get any grip with your hands, which makes the task of pushing the gap seal into tight spaces next to impossible. I resorted to using a flat head screwdriver instead and even then struggled. That being said, once you’ve got over the ordeal of trying to install the gapseal, it does seem to block out draughts very well.