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Understanding the energy efficiency ratings of windows

Who would have thought that buying new windows can be so complicated?  It’s easy and enjoyable to choose a new design and colour but how can you figure out the different energy efficiency ratings?  It really is important to get to grips with this as poor energy efficiency will adversely impact on your heating bills as well as the environment and potentially the value of your home should you want to sell it.

The energy performance of windows, skylights or Velux windows and doors, (don’t forget the doors), must be independently verified and certified by the National Fenestration Rating Council. Fenestration just means windows.  The NFRC is an independent not-for-profit organisation that is designed to promote energy-efficient manufacture and there to help consumers evaluate products against and make an informed decision on a purchase.  In order to hone in on good energy-efficient windows, consumers need to focus on products with an Energy Star rating.  This not only confirms the product’s status but allows you to easily compare one with another in terms of performance.

Performance Ratings

Start off by looking for the Energy Star on products.  There will be a label with a number of ratings and this is what they all mean – as advised by https://www.plasticbuildingsupplies.com/

  • U-Factor – this measures the insulating capability of the window or door and tells you the rate of transfer of the heat and essentially, how well the window or door will insulate. Normal figures would be in the range of 0.25-1.25 and the lower the figure, the higher insulating properties the product has
  • SHGC – Solar Heat Gain Coefficient – this is all about how the window or door blocks out heat caused by sunlight basically by measuring the amount of solar energy transmitted. The lower the SHGC, the less solar heat the window transmits
  • AL – Air Leakage – this test and rating tell you how much air passes through the joints in the window, measured in cubic feet over the area of one square foot on a per-minute basis. The lower the number given, the less air leaks out and so the more airtight the product is.  Most companies in the building industry are looking at products which have an AL of 0.3
  • VT – Visible Transmittance – this test evaluates the amount of light the window provides, anywhere from a rating of 0 through to 1 with the accepted range being 0.20 to 0.80. The higher the rating, the more light the product allows
  • Condensation Resistance – not to be overlooked, dripping windows are a constant source of irritation and work. Condensation Resistance is scored from 0 through to 100 and consumers are looking for the highest rating possible as this indicates the window or door’s resistance to water build-up

Buying new windows and doors is not a cheap exercise.  Once you have considered the styling and aesthetics, spend time checking out the ratings of your new product.  A poor environmental rating could impact negatively on your lifestyle, your investment and the value of your home.  There is a wide range of uPVC products which come with high star ratings and so plenty of choices to suit both your budget and your taste preferences.

How to make existing windows more energy efficient

There is of course the option of working on your existing windows to make them more energy efficient – these are normally inexpensive and simple to complete. If your goal is to become more energy efficient without the price tag, here are some top pointers for you:

Install Awnings to block sun

According to the US department of energy awnings can drastically reduce the amount of solar heat gained in your home by up to around 65% when used on southerly facing windows. Awnings placed on western-facing windows can actually reduce heat gained by up to a staggering 77%!

You can install individual awnings on single windows or you can choose awnings that will cater for larger windows throughout the home.

If you do decide on applying awnings in the home, ensure that you use good materials that are long-lasting. Newer, synthetic fabrics resist fading and mildew.

Window Caulk to prevent air seepage

Heat & cold can make its way into your home through spaces between glass, the window frame and window sash. Applying a reputable caulk or weather reliable stripping is definitely a relatively cheap and simple solution.

If you can feel any drafts around your windows, you’ll certainly want to make sure you seal the area in question. Many types of caulk & not to mention effective weather stripping materials will last a pretty long time, but you should definitely check them on a yearly basis to ensure the best possible weather protection.

Consider using window film

Tinted window film will certainly reduce the amount of heat that builds up inside your home from the sun. You can either choose temporary or permanent window films. You can also choose whether or not to apply the film professionally or give it a go yourself (we do recommend getting a professional to do the work for the best results)

Use Drapes or Blinds

Insulated drapes can improve your windows enery efficiency in both the winter and the summer. The thermal insulation can deter cold chills all the while preventing heat from leaving your home.Essentailly, using drapes is a benefit because you can open the drapes to let sunshine in to warm your home whenever you want.

Window blinds are also a terrific idea for reducing heat from the sun. Really well made blinds can reduce the heat by up to an astonishing 45%! Blinds are not that effective though for reducing heat lost in the winter, though.

Essentially, both blinds and draperies will maximise your sun protection and the prevention of heat loss throughout the winter – a perfect combination. Pull-down shades provide another option, they can be custom fitted to fit your windows perfectly.

Whichever method you try one thing is for certain – it’s entirely possible to increase your energy efficiency on a budget and many people are doing this and enjoying the benefits.

About Emily Rose

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