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Timber Windows

What is Low-E Glass?

Ordinarily, glass will allow solar energy to pass from one side of the Timber window to the other.  This includes the relatively narrow spectrum of visible wavelengths, as well as those higher and lower wavelengths (known respectively as infra-red and ultra-violet light).

This is bad news!

Ultraviolet light has a habit of bleaching materials it comes into contact with.  Fabrics and wallpaper will fade much more quickly if they’re exposed to UV for a significant period of the day.

Infra-red light poses a different problem, in that it’s transmitted into the building as heat.  If you’re looking to keep cool during a blisteringly hot summer’s day, you’re going to struggle – you might even be tempted to draw the curtains in order to keep the sunlight out.

The Low-E glass in our Timber Windows comes with a special coating that’s designed to act as a filter, allowing visible light through while excluding the superfluous wavelengths to either side.  This will allow your interior to enjoy the benefits of more light, without the downsides posed by ultraviolet and infra-red.

How low-E Glass Works

When heat or light strike a surface, that surface will absorb a portion of that energy and re-radiate it.  How large a portion this might be will depend on the surface in question.  If you’ve sat in a car with black leather seats on a summer’s day, you’ll know that dark materials tend to absorb and radiate more energy than reflective ones.

The amount of energy radiated by a surface is known as its emissivity. Glass, unfortunately, is naturally high in emissivity.  The more we can reduce this, the better an insulator our glass will be.

On the surface of each pane of low-E glass is a microscopically-thin coating that is designed to reflect infra-red rays.  This coating can be made from silver, or a variety of other metals, but their purpose is always the same: to deflect heat away from the glass.

Types of Low-E Glass

Low-E glass comes in two different varieties, and it’s produced using two different techniques.

A passive Low-E coating is built to contribute to the amount of heat within a home, preventing energy from leaving and thus lowering the heating bill.

A solar-control low-E coating works in the opposite way. It reduces the amount of energy entering the home, helping to keep it cool.

The right type of low-E glass for you will depend on the location of the building.

How is Low-E Glass Coated?

Each type of glass can be coated using one of two methods:

Pyrolytic

This process emerged in the 1970s.  It is applied to the glass shortly after production.  The coating fuses neatly with the hot glass before the latter has a chance to set, and stays that way for the entire lifespan of the window.  The glass is then cut to size and shipped.

Magnetron Sputter Vacuum Deposition (MSVD)

This process came a little bit later, in the 1980s.  It’s slightly different in that it’s applied to the sheets of glass after they’ve been cut to size, using a vacuum chamber and magnets to apply the coating at room temperature.

For many years, passive coatings were produced using the pyrolytic method, and solar-control coatings using the MSVD method.  More recently this line has begun to blur.

What does Low-E Glass Look Like?

So what effect, if any, does a low-emissivity coating have on the appearance of the window?  Since there are many different types of low-E coatings, and they can be applied at different thicknesses, it’s easy to be misled by reports of a set of ‘tinted’ low-E windows which block out certain colours, and distort the view of the exterior.

If, however, you want to ensure you don’t get any nasty surprises, it’s worth inspecting the sort of low-E glass you’re considering before making your purchase.

How Much UV Does Low-E Glass Block?

The thermal performance of windows is typically measured using the U-value.  This number refers to the amount of heat loss the glass permits per a given area.  According to the U-value, low-emissivity windows tend to be twice as efficient as their plain-glass counterparts – but it’s important that an impartial initiative backs up the manufacturer’s claims.

Naturally, this figure doesn’t cover the UV light that low-E glass will block.  Depending on the strength of the coating, low-E glass can prevent anywhere between 80% and 99% of ultraviolet light from entering the home (compared with around 60% by a standard window).  This extra protection is especially worthwhile if the sunlight entering a window is immediately falling on a set of curtains, a fabric-covered sofa, or a prized rug.

Contact us for a quote – Timber Windows Direct.

What U-Value Should your Timber Windows Have?

When you are looking for a new set of Timber windows, there’s one metric that you’re almost certain to encounter, the ‘U’ value. This number is a way of describing a window’s thermal efficiency, but what does it mean? What is the best U-value Timber window, and what is the U-value of double glazing?

How Does U-Value Work?

Let us start with some definitions.

A U-value is a measure of heat energy moved through a given area of material in a given period of time. This might be a Timber window, but it might equally be a wall or a door. It’s most often measured in watts per metres squared, when the difference in temperature between the two sides is one-degree Kelvin. Given that that’s a bit of a mouthful, we tend to say ‘W/m2K’ instead.

It’s important to note here that the U-value of a given window refers to its efficiency per square metre. So, two windows might have the same U-Value, but transmit heat at different rates because one is a different size to the other.

The lower its U-value, the better an insulator the window will be. If you’re aiming for the most thermally efficient house possible (as most of us are, cost permitting), you should almost always go for the Timber window of the lowest U-value.

How to Calculate the U-Value of a Window

If you’re buying a new Timber window, you’ll be able to see its U-value advertised by the manufacturer. Unfortunately, calculating a window’s U-value yourself isn’t particularly easy, nor are your calculations likely to be totally accurate.

For example, not every glass panel is manufactured to the exact same standards, and what stacks up in a laboratory might not translate into the real world. While there are bodies like the BFRC (which we’ll discuss in a minute) there to maintain quality standards, it’s important to treat claims about efficiency with a degree of scepticism.

Secondly, the glass panel isn’t the only thing you need to consider – the window frame also conducts heat, and will contribute to the thermal efficiency of the window. While it’s possible to account for this in your calculation, given that the interior of a window frame is made from a range of different materials, doing so can be very difficult.

To comply with building regulations, windows (like every other element of your property) must meet a certain minimum U-value. In the case of a window, it’s 1.6 W/m2K. Double-glazed windows, filled with argon, are typically 1.4 W/m2K, while thicker triple-glazed windows can go as low as 0.7 W/m2K.

The British Fenestration Rating Council provide a colour-coded rating system to help homeowners distinguish between different qualities of window. Good windows which keep the heat in are rated A or above. Bad ones are rated E or below. While this rating system is easy to follow, and will prevent buyers from making a mistake they will regret for years, it isn’t quite as specific as the U-value. As such, when you are looking for windows, we’d suggest looking for the U-value and spending your money accordingly. Obtaining a quote for windows with a good u value is easy.

Ultimately you will need to look beyond the lettered rating, and look at the U-value.

Timber Windows

Engineered Softwood Timber Windows

Timber Windows

Educate yourself about the engineered softwood used to manufacture Timber Windows

Softwood Engineered Timber Windows

This is the only softwood that we recommend using as it is ‘engineered’. This is a process where several pieces of softwood are glued together with opposing grain directions to form a single ‘laminated’ piece, this in turn leads to a very stable product, far outperforming solid generic softwoods. Less movement in the wood means that the paint or finish doesn’t have to flex as much, ultimately leading to longer periods between re-finishing and maintenance of your windows.

The process of bonding timber together to create a component that can be used in windows, doors, conservatories or stair cases has been used for over twenty years. However, it has only been in the last ten years that we have seen significant improvements with large European joinery companies investing in the equipment to produce laminated or engineered components in hardwood or softwood to compete against products offered by companies selling UPVC and aluminium clad systems.

The UK window and door market has been dominated by UPVC and composite products for the past 15 years. However, with the increase in availability of laminated timber components this has allowed the larger joinery manufacturers to produce high performance windows and doors in timber that offers a sustainable and attractive alternative to plastic or aluminium.

Why use Engineered Timber?

  • Timber bonded together in thickness and/or width offers greater stability over solid timber. • Wastage is reduced significantly during the manufacturing process, due to specific width and length availability. • Reduced production costs including labour. • Significant improvement in quality (defects removed) • Full utilisation of every component purchased. • Reduced stock holding • Reduction in waste removal.

Contact us for a quote to see for yourself how competitively priced our Timber windows are in comparison to UPVC.

www.timberwindows-direct.co.uk

Timber Windows

Timber Windows Online

Obtaining a quote for Timber Windows has never been easier.

The old method of contacting a window company to attend your property and measure up whist providing you there highly polished sales pitch is now redundant in our opinion!

Online sales of everything has taken a huge leap in recent years and buying timber windows is no different.

When customers start their journey for purchasing windows they generally have a very good idea as to which windows they want to buy.

We believe that it is not necessary to attend people’s property and present the highly polished sales pitch in order to put pressure on people to buy windows and doors.

Timber windows online

Timber Windows Online

 

Here at Timber Windows Direct we started sales via EBay and have grown into a very respectable online business.

Customers can roughly measure up their own windows to provide us rough measurements to quote them on – we will then attend the property and complete a full window survey to ensure the production measurements are correct.

This process removes the pressurised sales techniques that some companies use.

www.timberwindows-direct.co.uk provides many photos of our completed projects and the various types of windows that are available to the customer.

 

We are more than happy for our potential customers to come and see us and view our windows prior to placing an order as we are fully aware that some people wish to see the finished product prior to committing to an order, we are based in Bracknell Berkshire so please come and see us if you wish?

 

If you genuinely feel you need to have someone attend your property and conduct a full window survey then please get in touch and we will arrange for someone to attend and measure up but rest assured it will come with help and recommendations but no polished sales pitch!