# Due south, or south east glazing orientation?

| Posted in Green Building Techniques on
Ive used a calculator for roof overhang depth, and I believe the calc is designed to to simulate the south side of the home facing due south.. But Ive read some discussion, and seen some passive solar homes that are pointed south east.  Ive read it can eliminate summer afternoon/sundown rays from reaching the windows, but how do you calculate how many degrees off due south if this is true? Is there a calculator that I’m not aware of?   I do remember last summer thinking I should set my new home at a 45 degree angle to east and west for more shade on the east corner balcony in the summer afternoon, but this is essentially the same, but 45 degrees is to much I’m guessing..

Thanks

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### Replies

1. Expert Member
| | #1

In “The Natural House” Frank Lloyd Wright wrote, “the house should be set 30-60 to the south” -- that the ideal orientation of a building for catching the sun was to have all walls at either 60 or 30 degrees to south. When he started a plan he would take a 30-60-90 triangle, orient it so that the hypotenuse was pointed north, and sketch all of the walls with the legs. Fallingwater is oriented this way.

1. | | #7

Thanks for that DC.
I think your saying he aimed his south walls 30 degree's southeast. But when I eye ball the aerial view, fallingwater looks more like the 45 degrees I guessed I needed to shade my east side balcony.

2. | | #2

Sorry to be the dream crusher but the quant idea of passive solar homes is an abject failure in the real life but not for the lack trying and tons of money spent.

What we know today is windows make expensive poor preforming walls. Put in the windows you need for a great view but limit them to less than 20% of your wall area and build the smallest, tightest and well insulated home possible.

PS Try modeling your home with free BEopt software spin it 360° my bet is that the difference is less than \$50 from highest to lowest per year.

Walta

3. Expert Member
| | #3

mikeolder,

I certainly wouldn't advocate ignoring solar orientation when siting a house, but neither would I let it be the main determinant. How the house relates to it's immediate surroundings, the landscape, views, neighbours, etc. should all be given a lot of weight. If that meant it wasn't exactly optimized for solar gain and shading, that's alright.

1. Expert Member
| | #4

Even with that you have to be careful. There is a street in DC called Potomac Avenue, which sits on a bluff on the east bank of the Potomac overlooking the river. There are a row of large expensive houses with river views. I talked with an architect who worked on one of the houses, he said everyone wants big windows facing west to emphasize the river view, then within a year they're back asking for shades because the afternoon sun is so brutal.

4. | | #5

The kind of natural light you want to experience inside your house is also a factor to consider.
For example, I like to have my bedroom receiving east light, so that I wake up with the morning sunlight. It helps me to keep regulated to a natural body rhythm. There's plenty of research showing the health value of designing for the circadian rhythm.
For this reason I also advocate not going overboard with artificial light in spaces that are used in the evenings. Let the light levels come down, as they do naturally.

5. | | #6

Agree with walta, but facing slightly SE gives you morning sun and turns the shoulder away from Summer afternoon sun. Overglazing for solar gain is a waste of money but setting up to use what is there is advantageous

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