Effective Tips on How to Insulate Windows


Insulating windows for the winter is not a particularly difficult task, but there are subtleties and nuances. Basically, it is usually required to insulate old windows, including plastic ones that have been in use for a long time. Consider do-it-yourself window insulation, which can be done quickly and inexpensively. In its most simplified form, the technology of window insulation boils down to ensuring the tightness of all joints of window parts, especially in places where opening sashes are provided. In this article, we have gathered these effective tips on how to insulate windows. 

Old window insulation technology

The simplest and cheapest technology of sealing cracks in old windows using strips of paper, cotton wool, and paste today can bring a smile to many people. However, such insulation is simple, fast, and cheap. Indeed, such insulation is not for a modern apartment or three pane windows. But in old buildings, it is possible to use proven "old-fashioned" methods. In total, things are:

1. Use a knife blade to carefully seal the cracks in the windows with technical cotton wool

2. Stick the strips of paper on top with ordinary soap.

Thick paper tape for window insulation is sold in almost any building materials store and is inexpensive. Old technology can be combined with modern materials by using a special tape with an adhesive surface applied instead of paper and soap.

Modern technology of window insulation

To ensure high-quality and long-term insulation of wooden windows in an apartment for the winter, it is better to resort to modern technology using silicone sealant and/or synthetic sealing materials. To insulate windows with a sealant, it is better to purchase a lever syringe. The tube with the sealant is inserted into this simple device and the required amount of silicone is squeezed out of it by pressing the lever. It is better to use a transparent sealant, if it comes out on the glass, it will not be noticeable.

Window insulation with sealant

First, you need to remove the glass from the window. Using a sturdy flat-blade screwdriver, remove the wooden glazing beads holding the glass. To better fit the screwdriver into the joint between the frame and the glazing bead, sharpen its sting with a file or on a sharpening bar. Glazing beads are first lifted, as if "ripped" from their place, along the entire perimeter of the frame, then removed completely - first the lower one, then the side ones, and last of all, holding the glass, the upper one. After that, carefully and carefully remove the glass. This should be done with cloth gloves to avoid cuts.


Clean the glass seat from dust and dirt with a spatula and then apply a sealant bead around the frame perimeter using a lever syringe. After that, it remains for us to install the glass in place and fix it with glazing beads. How it all will look can be seen in the figure below.

When removed, old glazing beads often break, so pre-stock new ones (they are sold in construction markets, in construction supermarkets).

Indeed, it is best to repair and insulate windows at the same time, in this case, in addition to changing glazing beads, you can clean off peeling old paint, fill cracks and fallen out knots, change window accessories (wraps, awnings, etc.) to a newer and more attractive one.

Insulation of windows using a sealing cord (tube)

Insulation of windows at the junction of the opening elements (window frames, transoms, and vents) is done in a slightly different way, namely, using a special sealing cord. It is a flat tube of soft rubber with one side covered with an adhesive, like scotch tape, and covered with release tape. Often, these tubes are sold as twin tubes. You can also fix them both or one at a time (they are easily separated, without any tools). The sealing tube is placed in such a way that the window frame, when closing, presses it at a right angle, and does not slide over it.

It should be remembered that although the tubes are very soft, installed around the entire perimeter of the frame junction, they create significant resistance, therefore, the frame may have to be slightly suspended. While insulating old windows for the winter with your own hands, you can notice that some of the gaps are so large that the sealing tubes are even installed unnecessarily freely. Sealing gaskets are also made from other materials, in particular foam rubber, they are usually the cheapest, but they are rarely enough for more than one season.

Window insulation with film

Finally, you can consider window insulation with a film. There are special films, but they are not always on sale and are not cheap. Instead, it is quite possible to use ordinary plastic wrap, which is attached outside the window or, if impossible (if the window, for example, is located at a height that is difficult to reach) from the inside. 

Such insulation can be performed for the house, in the country, in outbuildings (the link tells how to build a veranda). The film is used to cover the entire window, securing it as close as possible to the outer edge of the frame. When fixing the film, it must be pulled evenly, avoiding slack, where the film will be poorly fixed, it will quickly ruffle with the wind.

Choosing a film for window insulation

The film for insulation is usually chosen based on the requirements of its transparency, often forgetting about such an important characteristic as frost resistance. The fact is that ordinary polyethylene transparent film becomes brittle at low temperatures and breaks like thin glass in winter winds. Therefore, when purchasing a film, ask the sellers what temperature it is designed for. Usually, a film that can withstand prolonged exposure to low temperatures has a yellowish color.

It is better to buy film in a construction supermarket, where the declared characteristics are usually more consistent with reality. If the aesthetic qualities are not particularly important, it is better to use a film designed for the device of the so-called vapor barrier or hydro-barrier. A distinctive feature of such films is that they are reinforced with fiberglass mesh and are usually designed for negative temperatures up to -40°F. True, such a film costs almost twice as much, but it will last three to four years.

How to attach a film to windows

The fastening of films to window frames is often performed with an industrial stapler. It is convenient and reliable. Especially if the work has to be done when the "white flies" have already flown and hands freeze in the winter wind. A stapler is a really good alternative to pushpins, even if you are insulating windows with your own hands, but you should keep in mind the following that the staple staples are thin, and sometimes the film breaks. To avoid this, you need to put some kind of lining under the bracket.

But if the appearance doesn’t really matter, ordinary cloth tape is also ok. If appearance matters, the cloth tape can be replaced with a plastic one, or the linings can be cut from an additional expensive, thick film, especially since it will not take much of it. The length of the staples should not be more than 0.3 inches, otherwise, when spring comes and you need to remove the film, you will have to pull them out.