Skylights on A-frame cabin

[Tony]

Any thoughts on the best fixed (non-opening) skylights to use on an A-frame cabin at Lake Tahoe with a wood shake roof? The roof pitch is 18:12.  The county building department told me the snow load for my area is 256, but I was not able to ask for a further definition. One local glass company said Velux windows would not work because of the roof pitch.  The roofing contractor I've used in the past is trying to be helpful, but everyone is so busy it's impossible to get the principals together with me at the same time to hash out what should be done.

[glenn-k]

That would be your snow load in lbs per square foot.  It would take a heavy duty skylight and no protrusions I assume.  A 6 square foot skylight could have a snow weight of 1536 lbs on it - I don't think that applies the same to an A-frame..  It is also quite common for skylights to have leakage  problems.  

We put one in my sons roof - no snow - it was always too hot- he put a towel over it.

[Tony]

Thanks for the explanation.

I installed a skylight myself on a flat roof home I owned on the coast years ago.  No leaks, but the intense sun was a problem.  I bought some camoflage netting at a military surplus store and draped it over the opening.

[Daddymem]

If it is light you are seeking, could you go with one of those tubular skylights?  They are really good at amplifying the sunlight right into your room.  I think I have seen some "extreme weather" ones at HD.  Obviously this won't work if you want to be able to look out the skylight.

[jraabe]

The classic way to get light into steep roofed buildings in heavy snow country is to build a small gable dormer with a vertical window. This moves the snow to either side and a vertical window doesn't have the heat gain characteristics that can be a problem in southern latitudes such as where you are.

Skylights work great in the cloudy north but you have at least two good reasons not to build them into this A-frame.

[Amanda_931]

I came up with a combination of John's and Daddymem's--a teensy shed gable sticking out about a foot and between two rafters (more with overhang in both dimensions) with a suntube^tm or one of its clones.  Up as high as possible--so less snow can pile on it.

But a long narrow window in a gable dormer would look and probably work better.

Susan Susanka had an article somewhere recently about designing daylight into difficult places.  Skylights are the last resort.  For exactly reasons that other people have mentioned.

[Tony]

John, the gable dormer is a really good idea, especially since whatever is installed would be on the sunny south-facing side of the cabin.  I'll look into it.  It would probably be quite a bit more expensive than a simple skylight but saving money to install something that leaks in the winter and bakes me in the summer doesn't sound like much of a bargain.

A suntube would be less appealing to me, but it's worth considering.

Amanda, if you have a photo of your installation that you can easily send to me, please do.

Thanks!

[Daddymem]

Actually, now that I think of it, I know a house that has something that might work for you.  This house is an A-frame...sort of.  Instead of coming to a peak there is a shallow peaked flat top.  Anyways, the "roof" goes all the way to the ground like an A-frame.  They installed double hung windows vertically by building out a really, really, really small dormer...just enough to get out to the top of the window while the bottom of the window fit against the roof.  It seemed to work for them.

[Tony]

Susan Susanka had an article somewhere recently about designing daylight into difficult places.

A Google search revealed that Susan (Sarah?) Susanka has a series of "small house" books and articles for sale. Can you help me by narrowing down the field somewhat? Thanks!

Tony

[Daddymem]

Sarah Susanka...I know she covers some of the daylight concepts in her Not So Big series.