To Screen or Not to Screen?

A stay at home case study on solar screens and other home cooling techniques

Are you unknowingly heating the inside of your home in the summer with solar energy?

Solar energy coming through your windows may be a welcome friend in winter but it’s an unwelcome guest in the summer. Whether you’d like to stay cooler, reduce your summer air conditioning bill, or both, there are some surprisingly effective and greatly underappreciated things you can do.

First of all, most people don’t know how much their drapes or shades do to help heat their home in the summertime. Here are some pictures showing just how effective an indoor drape really is in heating you up.

 

Most people think closing their curtains or miniblinds helps keep their home cooler, but do they really? From top to bottom we have –

  • A vinyl-coated curtain, bright white on the side facing the window

solar shading nevada county

  • A room that’s 71 degrees (based on the temperature of an inside wall)

  • A curtain that’s 87.5 degrees

  • A curtain that’s just 73.5 degrees when a solar screen covers the window outside

The takeaways from this are –

  1. The curtain, despite being bright white, is actually a pretty effective solar collector, coming in about 17 degrees hotter than the room
  2. The solar screen reduces the curtain temperature 14 degrees, an 82% reduction
  3. This is not the only window in the room. Add them all up and you have even more solar collectors
  4. A solar screen on the outside is far more effective than even a bright white shade on the inside

Awnings are another alternative, actually anything that substantially shades a window on the outside will make the most difference.

The key is to shade your window from the outside.

Here’s a recent example of another approach I saw recently.  

I know someone who has a sliding glass door in their master bedroom that faces west. The room gets really hot in the afternoon, even with the air conditioning on. The problem went away after they put a patio umbrella up on the deck outside the slider.

Now they’re not only more comfortable, but they’re saving on their air conditioning bill too!