This project is presented by Gapseal
Summary: How to correctly seal gaps in sash windows using Gapseal even if they are irregular in size and also how to seal the gap between the 2 window sections and ensure that they are suitably draught proofed to prevent heat loss in your home
Sealing sash windows to stop draughts is difficult. With the window halves sliding up and down, they tend to rip off any glued-on window seals. The gaps are also irregular over the length of the channels of the frame so that sometimes several layers of traditional sticky seals are applied leading to even bigger problems with peeling. It is also almost impossible to seal the space between the two window halves. It is certainly impossible if you do not want to show the seal when the window is opened in the summer.
The sash window seal Gapseal offers here a solution. It is a flexible, non-permanent window sealer, which can be inserted at the onset of the cold time of year and removed in spring when the sash windows are used again. It can be used many times, does not absorb moisture and will bridge most gaps.
Application is fast and easy. The sealant is pushed into the gaps around the window with a handy applicator. The sealant stretches so that small gaps can also be successfully filled. Once inserted, the magnolia coloured seals are invisible to the eye. The seal will always try to expand to its original size, making it fill any gaps created through expansion or contraction of the wooden frames.
Unlike traditional seals which will make the sash windows almost impossible to open, Gapseal is quickly removed in spring which ensures that the sash window will fully and easily open again.
Gapseal also stops unsightly, blackened old window seals with dirty dust edges. It stops insect infestation and any rattling of the window.
The seal can also be used on outward opening windows with uneven gaps

The completed job - your window now sealed successfully!