I need to replace my roof. Is it possible (allowed by code) to turn my attic into a greenhouse?

Question

I've been told by my insurance company that I need to replace my roof. It doesn't leak, it's just old and due to be replaced. I'd like to do something "different" with it and make a usable space out of the currently unusable attic. I was thinking it would be great if I could strip off the roof and replace it with greenhouse material to turn the attic into a mini-greenhouse. The house is a 1930s craftsman and I live in San Diego.

I need to know if, first, this is possible and, second, if there's any chance in hell that it would be deemed okay by a city like San Diego. If not, what's the primary objection that the city would have with the idea? Are there any examples of other people doing this anywhere in the US?

The house is only 700 sq ft. so we're not talking massive greenhouse here. Also, I've seen greenhouses made from lightweight plastics rather than heavy glass. I think the comment about the solarium is right on. Even if it's not suitable for growing plants, I'd like a "functional" and "green" roof. That's really the intent.

BTW, I live in San Diego. Hail really isn't an issue.

Answer 1

You'll have to check with your local code enforcement agency to see. My guess is you'll run into problems with fire safety issues or with foundation. The other issue you're going to run into is that greenhouses are wet, so you'll need to build sort of a waterproof floor, with proper drains, to keep water out of the house structure.

I know of several commercial buildings with greenhouses on top, most in university settings. e.g.: http://www.fpm.iastate.edu/maps/building.asp?id=14

Answer 2

First thing you need to do is check with your local code enforcement agency. If in fact there are no laws governing residential glass roofing; your issues will just begin with approval.

Certainly there are restaurants/ malls/ etc. that have partial glassed in roof areas; and you might consider that too; similar to skylights; which are acceptable. Yours might just be on a larger scale.

I suggest you'd have to have the home structure checked for the stability of it; and the load it might have to bear. The glass would have to be substantial; not usual window pane glass; and framed well; sealed well; and very likely you'd have to consider rolling shutters. It should be tinted; and yada yada yada.

The idea is great. To put it into a practical application might be a nightmare.

Steven Wolf

ADDED THOUGHT: If approved; or even considered; you might be asked your intent. It might seem a bit abstract to have a greenhouse of that magnitude; just for plants you intend to use around the home? Or perhaps you might state it more as a Solarium? I suspect they might suspect other agendas?

Answer 3

I wouldn't go up there: Setting up cameras in the bathroom and kitchen would be the best bet. If you don't see anything on tape after a long time, Call exterminator and say that there are rats in the attic, he may find a person or he may just find that your problem was an animal all along (Make sure he checks any crawlspaces etc.) Or you could just turn up the heat in your vents all the way and it should be obvious if there is a person in there. Or you house could be haunted, you may want to move out if you believe in that sort of thing.

Answer 4

from my point of view at first blush it sound neat. on 2nd thought what a nightmare from the building point of view your ceiling joist are not meant for that kind of load first off. next your usable space would be cut down due to having to put up walls that would probably give you about a 24x24 foot room at best you would need to use some other material than glass. I added a 15x12 green room on to my house and used the solid sides of sliding patio doors that were double glazed and have gone Thur 3 hail storms ok so far .ask your insurance agent if they would insure it if you built it and if so HOW MUCH? THE COST WOULD BE ABOUT 3X THE COST OF A NEW ROOF.

Answer 5

i do not know i mean especially since greenhouses have a glass roof and along comes the first hailstorm and bang your roof is gone. i do not think it is a good idea even if it was allowed