Does the best wood for windows make the most energy efficient windows?

Wood has long been the traditional choice for crafting windows, but what is the best wood for windows and is wood the go to material if you want energy efficient windows? Also, what other factors come into play? For example, how much do energy efficient windows save? How much do energy efficient windows cost? To explore more about energy-efficient windows, we must first define what they are.

What are energy efficient windows?

Energy efficient windows are windows that excel at keeping the heat in and the cold out. This minimizes heat loss, reduces the need for heating and use of energy. This makes your home more energy efficient. Double or triple glazing can make a big difference in reducing heat loss but the window frames can also contribute to their efficiency.

What window frame options are available?

Wood isn’t the only material available for window frames but it is the only genuinely natural one. To help you choose the right type of windows for your project, let’s examine all the options:

Wood window frames

Look natural, are eco-friendly, have excellent insulation benefits which help to reduce heat loss and can be easily painted or stained. They do need regular maintenance though to avoid insect damage rot and warping.

Accoya wood window frames

Incredibly durable high-performance, low-maintenance modified wood. Thanks to its outstanding dimensional stability, Accoya resists swelling and warping – meaning your windows won’t stick or become difficult to open over time. It’s also highly sustainable, non-toxic, and resistant to rot, insects, and moisture, with all timber sourced from FSC-certified softwood.

PVC window frames

Whilst affordable, weather resistant and low maintenance, PVC window frames are less attractive than natural wood and can quickly fade and discolor, looking dated and tired over time. They can also warp and degrade over time and being petroleum-based, they are not remotely eco-friendly.

Aluminum window frames

Strong, slim and better suited to large glass areas and modern properties, aluminum frames are low maintenance and have a long lifespan. The downside is they cost more than PVC or vinyl, are poor insulators which can cause condensation and they not as environmentally friendly as wood.

Vinyl window frames

Despite being the low-budget option, vinyl window frames are low maintenance, moisture resistant and are more energy efficient than aluminum. They do, however, offer limited color options, can warp or crack in high temperatures and look cheap compared to aluminum and PVC.

What types of wood windows are available?

Wood can be used to create a wide variety of different energy efficient windows. The styles of windows include:

Sash windows: Wood sash windows are elegant with their vertical sliding panels, perfect for Georgian and Victorian homes. They reduce draughts and are non-toxic, making them both stylish and healthy.

Casement windows: Casement windows are hinged on the sides, and open outwards for excellent ventilation – ideal for kitchens and bathrooms. French casements offer unobstructed views and ample natural light.

Bay windows: Bay windows project outward, adding light and space while offering panoramic views. Their Edwardian charm enhances both the interior and exterior of any home.

Wooden shutters: Wooden shutters have a fantastic ability to control light and temperature efficiently. Wooden shutters can help regulate temperature in any building, allowing heat retention during the winter and cooling.

What is the best wood for windows?

The best wood for windows is the one that hits the sweet spot of having the best combination of long lifespan, impressive thermal values, little maintenance, excellent dimensional stability and the reassurance of an impressive long-term warranty.

Compared to all unmodified softwoods, including pine, cedar, spruce, Douglas fir and redwood, plus hardwoods such as sapele, oak, meranti and iroko, Accoya acetylated wood ticks all the right boxes for energy efficient windows. That makes it, on balance, the best wood for windows. But how is acetylated wood made and why does it make such durable and energy efficient windows?

Accoya wood, through its proprietary acetylation process, which effectively “pickles” the wood, becomes highly water-resistant through the molecular changes which additionally enhances its durability. This makes it highly resilient against harsh conditions, and insects no longer recognize it as wood, so they typically avoid it.

In terms of energy efficiency, acetylated wood has excellent insulative properties. Depending upon the design of the window, it can achieve an impressive U-value of up to 1.2 W/m²K. Compared to standard types of wood, thermal conductivity of Accoya is superior to softwood by 8% and 30% better than hardwood. Couple that with its enhanced durability and stability, and it provides long-term energy efficiency and superior overall window performance.

How much do energy efficient windows cost?

To pinpoint which is the best wood in terms of energy efficiency, we have to take the cost and longevity into account. This gives you a clear picture of how good the value of each is. Let’s start from the cheapest in terms of purchase price:

$ Vinyl window frames are the cheapest option however despite being fairly low maintenance energy efficient windows, they do look cheap and unnatural.

$$ PVC window frames are basic, cost a little more than vinyl, are not quite as energy efficient and are moderately durable.

$$$ Wood window frames are a mid-priced option that offer good insulation, however they high-maintenance and are only moderately durable.

$$$ Aluminum window frames are the least energy efficient windows, but are durable, modern looking and require little maintenance – they are a relatively expensive though.

$$$$ Accoya acetylated wood window frames are the most premium energy efficient window frames of all the options. Their high-performance and excellent durability mean they offer the greatest value and most natural aesthetics over their lifespan. Impressive 25 to 50 year warranties give long-term peace of mind, too. Although Accoya window frames are the most premium, overall, the cost of a window doesn’t increase massively as there are so many other components such as the glazing and hardware, so the frames are only a part of the costs.

How much do energy efficient windows save?

This is the big question on every buyer’s lips. Nobody wants to go through the process of choosing window frames and the expense and inconvenience of having them installed only to be disappointed by their energy efficiency when the utility bills hit. Obviously, double and triple glazing make a difference, but in terms of the energy efficiency of the window frames, you need to look at the U-values of the frames.

The U-value is a measure for how well a window insulates by quantifying the rate of heat transfer through it. A lower U-value means better insulation and energy efficiency.