Do Wood Window Frames Offer Sufficient Insulation?

You may have made the assumption that wood is a low-performing choice for window frames, especially since it seems that old timber frames are constantly being replaced by uPVC casement alternatives. Yet, this is far from the truth. Wood is still an excellent choice for window frames thanks to its strength and functionality. However, to give a clearer picture as to whether wood frames provide adequate insulation we will consider various properties and benefits that wood offers as a material choice for window frames. See here for solidor door designer.

Window Insulation

What are the features of a window that means it is insulated well or that it is poorly insulated? In addition, as the search continues for designs and materials that will provide superior performance, where does wood sit in the available choices?

The Basics

For both double and triple glazing, the main focus is on the structure of the glazing. There is a gap between the glass panes and this space is filled with argon or another inert gas that is heavier than the air that surrounds it. It is this design that makes double or triple glazed windows provide a high thermal performance. That being said, the actual frame can play a key role in how well the window performs overall. Standard casement windows have both a seal and a thermal break which work together to provide a defence against heat loss through the actual frame.

Energy Performance

By natural design, wood is a low conductor of heat. Actually, unlike materials used for other frames that require a thermal break, solid wood frames do not require this feature as they are naturally well insulated. Incredibly, wood in its natural state offers a staggering 400 times more insulation than steel and more than double that of aluminium. This means that it does not put the same dependence on the surrounding casement engineering to provide a high energy performance.


Noise insulation follows a similar path. Being porous, wood has tiny air pockets which add to the level of sound insulation. When a solid wood frame is combined with double or triple glazing the wood can provide higher performance when it comes to noise entering the home than any other material.


Of course, everyone in the UK wants their home to keep in the heat during the winter months, however, this isn’t the case when we have those enjoyable hot summer moments! Wood is a low conductor of heat so it will not contribute to heat being transferred into the home. This works in the same way during winter. Heat transfer is mostly down to the glazing. It is possible to regulate heat in the home to a much better level if the glass in the windows has a UV coating. Hence why glazing technology and the way it is constantly evolving is of such benefit as it can do much to prevent an excessive amount of heat from penetrating the glazing.

Properties Of Wood

One of the fundamental features of wood is that it is eco-friendly, indeed compared to all other frame materials it has the lowest heat conductivity. Manufacturing wood frames releases fewer toxins and also requires less energy. This ticks a lot of boxes when it comes to sustainability. Wood is flexible and can be formed with ease to a finish and colour that is desired. So long as the wooden frame is cared for well it will actually become more durable with age. This easily explains why wood continues to be used in building projects of all sizes.

Are There Any Negatives?

Since wood is a natural material that performs so well, why do we not see it being more widely used?

Maintenance Needs

The most significant negative related to wood for window frames is the maintenance. Maintenance needs to be regular and conscientious, in fact, it needs to be treated and painted for its full lifespan or it will suffer rot or warping. If this happens, the whole window system will have to be replaced.