What is Gapseal?

How Does it Fill Window Gaps?

Gapseal sash window gap filler has been cleverly manufactured with thousands of tiny, concealed air pockets which allow it to be compressed by almost 90% of its original profile.

These flexible properties allow Gapseal to be easily fitted into sash window gaps much smaller than its original width by stretching and compressing it during the installation process. Once the sash window filler has been inserted into the gap it will expand until it fills the entire width of the gap.

Wooden sash windows naturally contract and expand throughout the course of their life. These variations often create varying gap widths which can cause alternative methods such as scrunched up newspaper to fall out or absorb moisture which can lead to rotting and discolouration.

Gapseal can easily be removed when the window needs to be opened and is designed to expand and contract with the movement pattern of the timber and will therefore remain in place retaining the insulation.

Easy Fitting with No Mess

Gapseal has a profile of 8mm and is suitable for sash window gaps between 2 and 7mm. Our quick and easy fitting process can be completed by any competent person with limited DIY knowledge or experience and requires no adhesive, specialist skills or tools. We have also created a helpful installation video to demonstrate the fitting process.

Every order is supplied with a FREE applicator which is specially designed to push Gapseal into the gaps around your sash windows without damaging them.

Natural "Two-Tone" Appearance

The design of Gapseal follows extensive research and testing which has been carried out to ensure that the product is not only efficient but also aesthetically pleasing when installed into the sash window gaps.

The colour "Two-Tone Magnolia™" has been carefully developed to allow the gaps around sash windows to be sealed without compromising the natural appearance of the window.