Nothing beats natural lighting. It gives you a feeling of being outside and both warms and brightens the room and moods of us inside too. Plus it is free! It wasn’t too long ago that I was a starving student and I am not at all embarrassed to say that I still do enjoy lovely things that are free. Yippie!
So yesterday’s post was all about energy efficient lighting. But funny enough, I didn’t mention solar lighting. It’s the lowest energy light we have!
Lighting is a sizeable portion of most people’s electricity use; averaging 17% in the US and 15% in the UK for residential bills. So using low energy lighting and making the most of the sunshine really can make a large impact to a home’s overall energy use. While every home has windows, skylights are a particularly underutilized feature. But I think they are returning to popularity. And the range of options in skylight installations has been quite exciting.
When we bought our top floor flat 6 years ago, we asked the previous owner if the square hatch-looking structure in the hall ceiling was the loft hatch. When she said that is was not a hatch, but rather one of three former skylights that she had closed off, my heart sank. Why did she close them, I asked, trying to hide the bewilderment and anger in my voice. Her answer was that she was tired of them leaking… So, needless to say, we have had grand plan to reinstate them ever since. But cost and hassle have been the driving factors for these poor shafts staying closed.
But now it is time to open then up again and make the most of Edinburgh’s glorious 20-hour days in the summer. So, here are some choice tidbits of skylight info that I have been pouring over as of late.
Just like South facing windows let in glorious direct light, so too do skylights on the southern slope of rooftops. There are equations you can use to calculate optimal pitch based on your latitude, but these are more important for keeping summer heat to a minimum. Perhaps there are folks in the Southern UK who complain about summer heat, but being a native Southern Californian, I have been known to wear my down jacket in July since moving to Scotland!
Lots so choice in materials
There is now triple glazing available for skylights, although those in the US will have to wait to get this option. Glass can be double or triple glazed and coated with super extra energy saving films. Both glass and plastic are widely used, but plastic (acrylic or polycarbonate) cost less, weigh less and are more likely to scratch and discolour with age.
What in the world is a U-value? Well, it is the measure of a skylight’s insulation value, and the lower the number, the better it insulates. The top of the line triple glazed glass skylight can reach an astounding 0.58 U-factor, while an uncoated double glazed glass can have a U-factor of 1.1.