NW Door and Window Repairs Blog

Find out how to draft proof your windows for winter

Draft Proofing Windows

Help Keep Yourself Warm This Winter

When draft proofing your windows and doors, it is possibly the most cost effective and efficient way to help keep you warm.

By doing it correctly, it will eliminate the cold air entering a building, and prevent the hot air escaping.

There are a lot of options out there, that all claim to be effective draft proofing options for windows and doors.

And although there are a lot of options, these are categorised to different materials.

Different types of doors and windows require different draft proofing.

This is where a lot of confusion happens, and in a lot of cases further breaks the windows.

Basically – by using the wrong material on the wrong type, you may require further repairs.

Below is NW Door and Window Repairs Guide to eliminate drafts from your home safely, and correctly.  


Most Common Window Materials

We will start with the most common window material upvc, and why they tend to start having drafts only after few years from when they were installed.

(Spoiler – The simple answer is maintenance!)

We will go through a couple of steps on what you can do to eliminate the draft by yourself.

In this part, we will cover hinges, mastics and gaskets.

Draft Proofing How To Guide

  • Step 1: 

First, clean the inside of the rebate of the window.

Pay attention to what is known as the “v point”.

Cleaning hinges by getting out debris will help the hinges close correctly pulling in the window tighter.

Then apply some gt85 to relubricate the hinges and see if this helps after opening and closing the window vigorously.

If not, and there is still a gap, then you will need to replace the hinges.

  • Step 2: 

The second most common place air leaks happen is the case of gaskets.

Gasket shrinkage is most common, or moulded gaskets crack and perish.

This also enables the glass to become a loose fit.

This happens over time, and is a simple swap replacement.

The only thing you’ll need is a “like for like” match, so a sample is sometimes required.

We have 3 different places where gaskets are required, and each is a different variant of gasket:

Wedge gasket

This gasket is only required on externally glazed windows.

It goes between the frame and glass internally on older windows.

It starts at 2mm and goes up to generally 8mm.

On upvc, compress the glass to the external bead, making sure that when this is replaced, to snip it 1 inch longer.

Press it down, so when it is stuck, it covers the corners stopping drafts for coming back in future.

Rebate gasket

This could be flipper type, or a bubble type of gasket.

They both have an arrow shape to clip onto the window into a small groove.

This again will need sizing up with samples, as there are a number of different sizes available.

Bead gasket

This is probably the least “do it yourself” gasket to replace, as this could be clipped in or moulded on depending on the window.

At this point, I would say to get the professionals in to replace this gasket, as it will required to remove the glass.

Mastics And Sealing The Window

Believe it or not, not all window fitters are good at sealing the windows.

And as 1 rule, I think windows should always be foam filled.

Not only does this fix the window with greater strength, but there is also no cavity left over for the wind to howl through.

Once all of the expanding foam has set, trim it and mastic for that professional finish.