Why should you seal sash window gaps?

Why GapSeal is Different?

Traditional window seals usually have to be glued to the side of windows or frames and get stripped off when the sash window is opened or closed. They are usually hard to fit and generally not effective for windows that no longer open or that have painted and uneven surfaces.

Gapseal is designed to expand and contract with the movement pattern of the timber and has thousands of tiny, concealed air pockets which allows it to be compressed by almost 90% of its original profile.

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

Easy installation with no mess

Gapseal sash window gap filler is extremely easy to install and can be completed by any competent person without the need for messy adhesives.

The specially designed Gapseal application tool, which is supplied FREE with every order, will ensure that your sash window draught excluder is inserted to the correct depth within your windows gaps.

To make things even easier, our clear, step-by-step fitting guide walks you through the fitting process from start to finish giving you a warmer, more energy-efficient home with minimal fuss.

Ideal for different size gaps

Gapseal is the most reliable solution to fill the gaps around your sash windows. Its pliable form allows it to be easily pushed into gaps much smaller than its original size, making it ideal for sealing windows with gaps between 2 and 7mm.

Unlike other methods of sealing sash windows gaps, Gapseal also allows the window to be re-sealed after the window has been opened.

Gapseal is supplied with a free applicator and is available in lengths of 10m which is enough to seal around 2 to 3 average sized sash windows.

Natural complementary finish

Worried about how your sash windows will look after filling the gaps around them with GapSeal?

Our specially formulated Two-Tone Magnolia™ colour is designed to complement windows with a white, cream or light brown finish but the seal can be used in sash windows of any colour.

Take a look at our image gallery to see real examples of how windows can look after fitting GapSeal.

Fantastic energy savings

The gaps around sash windows can add up to a total length of up to 4m. This is the equivalent of having a hole the size of a down pipe through your wall and can mean significant heat loss, uncomfortable rooms and unnecessarily high energy costs during the winter months.

By sealing these draughty gaps, GapSeal can help you:

• Reduce cold draughts and heat loss
• Lower your annual energy bills
• Make your home more comfortable

Step 1 - Preparation of the Windows

Before fitting GapSeal you need to ensure that the gap between the window and the frame is clean and free from dirt and debris which can be removed using the applicator provided or an appropriate tool such as an old credit card, a blunt knife or a screwdriver.

Use a vacuum cleaner with a soft brush or crevice tool attachment to remove everything thoroughly.

When removing debris from around windows, care should be taken to avoid injury from old, damaged windows and frames.

Step 2 - Starting the Application

Using the applicator provided push the end of the GapSeal into the gap at the end of the window frame. Continue to push the GapSeal into the first 1-2 inches of the window gap to ensure that the seal is firmly in place.

A secure start is key to a smooth and long-lasting installation so make sure it is firmly secure before moving on to the rest of the application.

To make the first part of the installation easier the end of the GapSeal strip can be carefully trimmed into a point using a pair of scissors, this will allow the end of the seal to be pushed into the window gap easily.

Step 3 - Using the Applicator

After you have fitted GapSeal into the first 1 - 2 inches of the gap and the end is firmly in place, stretch the windows seal as much as necessary to push it into the gap without using excessive force.

Work a short section at a time, the resistance against the applicator should feel comfortable and not too strained.

Repeat this process for the full length of the window gap, the ideal depth is 2-3mm below the surface of the window frame.

Step 4 - Cutting to Size

After you have fitted GapSeal to the full window and are reaching the end of the gap. Measure the remaining length and trim the GapSeal accordingly, leaving approximately 1 inch of surplus material.

This extra length helps ensure a snug, secure fit during the final stage of installation and allows for any minor movement in the wood or shrinkage that may occur over time.

You can cut GapSeal to size easily using a pair of household scissors.

Step 5 - Finishing the Application

Once GapSeal has been trimmed to size, use the applicator supplied or an appropriate tool such as an old credit card or a screwdriver to push the sealant into the remaining window gap.

This final step ensures a seamless finish and keeps the GapSeal securely in place creating a long-lasting installation.

Repeat steps 1-5 for each of the windows that you would like to seal against cold draughts.

Safety Tip - Avoid Injury Risks

The application tool is extremely effective because of its specially designed shape. It is however important to remember that excessive use of force can result in injury.

To eliminate the risk of injury, never work the applicator toward your face and always maintain a safe distance between it and your leading hand.

The applicator should never be used as a toy and should be stored safely out of reach of children and pets.

Important Information

If you are installing GapSeal in a room with an open fire or a gas fire, make sure that an adequate flow of air is maintained at all times as blocking airflow can lead to a dangerous build-up of carbon monoxide.

To avoid this while still preventing draughts throughout the room, consider fitting shuttable air inlets in the floor close to the fire. These can provide ventilation when needed without reducing the overall comfort of the space or affecting energy performance.