WOW! Now that's a project. punching holes may not be necessary, I assume there's a drain in the bottom of your pool?

You might have to build a floor as most pools that I'm familiar with have a slope and you'd want to keep your benches level. Not sure how you'd procede but what an AWESOME idea....hehe

Dave
Milwaukee

You could fill the bottom to level with black rock or some other type of rock that packs well. I think it is a great idea and I am VERY envious. Orthos puts out a GH book, and pit greenhouses are discussed.
There is info online and I would suggest reading everything you can before you start. Try not to punch holes in the bottom of the pool. Maybe someday it could be reverted back to a pool if prioritites change.

Yes, good idea, that's why I feel a little bad throwing a couple of "killer balls."

Is the pool gunnite or liner? How well does the soil perc? Holes in gunnite or vinyl liner might drain through adequately, depending on how well your soil percs. Around here, where we have clay soil and vinyl liner pools, such a pithouse would likely fill with water without the pressure of the water within the liner to keep it out.

The drain, without modifications, won't help much. It probably comes back up to deck level where it attaches to the pool pump. The line would simply fill with drain water. You would have to keep a pump on the other end to keep it functional. Alternatively, you could figure a way to dig this drain line out and run it out to daylight, but this would require that the pool be set on a hillside or steep slope. If you can figure out this drain issue, the issue of water seeping in wouldn't be such a big deal.

Finally, to comfortably work, you'll need perhaps 5 feet of headroom on the sides. My pool, like most pools, has a shallow end 3 to 3.5 feet deep. To get enough headroom, you would either need to dig out the shallow end or build about a 3 foot sidewall all the way around the perimeter of the pool.

These aren't insurmountable obstacles, just a couple of potential problems that come to mind. Give us more details on the pool and let us throw around some more specific thoughts and ideas.

Head room shouldn't be a problem if they build a 4-5' Greenhouse on top of the pool, I guess that's what I imagine. Five foot of head room is definately too low, especially if they have baskets hanging from the ceiling.

At the deep end, it would be 10+' of headroom, which is excellent for climbing vines such as beans, tomatoes, or the occasional palm tree.

If the gravel is deep enough, drainage shouldn't be a problem should it? I have pea gravel that is 6" deep and shade cloth over the top of that for my floor. Draingage hasn't been a problem, just adds to the humidity. I guess it depends if they water or use overhead irrigation that floods the place.

Weebus, wouldn't you guess that s/he just intends to fill in the deep end and level it off with the shallow end? A GH with 4-5' side walls would certainly work, but s/he only mentioned putting a "top" over the pool.

If I were to empty my pool and remove or perforate the liner, and fill the deep end with gravel, what I'm afraid I would get is the same thing as I would with a big hole out in the yard...groundwater seeping into the space and eventually filling up at least a portion of the hole.

I got it...a sump pump. No holes in the liner or in the gunnite. Put a sump pump down in the deep end and pump any seepage back out and use it for watering plants.

Here's another idea: on the north side build an insulated wall. Build the "roof" on a south-facing slant to take greatest advantage of the winter sun and gain some headroom at the same time.

SB

Why would they haveto level it off at the shallow end. Could they put a step in around Oh, I don't know, the 6' area? I would really try and keep that deep end...

Be careful about the water table around the pool. I've seen empty pools pop right out of the ground during rainy season. It will float out just like a boat. I don't think even a few holes in the bottom would counteract it either. I also think you should keep the greenhouse sidewalls to a min to minimize heat loss at night. Just passing on what I've read.

Our neighborhood pool floated up several years ago. what a mess. had to be completely redone. expensive. Me thinks you should contact a pool service company and inquire about "floating pool syndrome" and how to prevent it if you are going to do a greenhouse in it.

Very clever concept. Of course, flat roofs don't get much winter sunlight (except in the tropics), so I would suspect that you'd want a raised top even if you didn't have a "shallow end" issue to deal with. Also, consider making your pool walls as reflective as possible. Light will be at a premium here.

As for the drain issue, even if the drain comes up to deck level and would normally need a pump, I see one possible alternative. If you converted it into a siphon, you could drain water out without using power if you kept the drain tube full at all times (this would likely leaving a little water on the ground under your "floor" -- crushed rock?). A pump would probably be simpler. I wouldn't want to risk holes in the floor -- you don't want groundwater coming in after a heavy rain, do you?

I'd like to revive this thread, as I'm considering this very project at the moment. I have a concrete pool that is about 3 feet above ground and otherwise inground. It was poorly designed as a pool but I think it would make an excellent foundation for a solar greenhouse. I don't think pit-style would be correct because there is no drain (I'm not kidding) so I'd probably put flooring over the pool cavity itself, level with the deck, and I'm trying to think of ways to use that space underneath - incorporate a pond or heat storage or something. If anyone's ever heard of anything like this or wants to toss out suggestions, I'd be grateful for any guidance! Also, I'd like to build this thing with a mix of cob and strawbale (sort of like what the folks at Pendle Hill in Pennsylvania have done with their greenhouse), if that should mean anything to anyone. Many thanks!! - Maggie

Karenrei mentioned "flat roofs don't get much winter sunlight". I wouldn`t worry about it ;)

You`ll find the diffuse light from directly above is actually much better quality than most low angle direct winter sunshine

I was searching for information on this subject and came across this thread. Does anyone have anything to add? Here's a website of a family in AZ who converted their swimming pool. I just saw it and haven't read much about it yet.

Here is a link that might be useful: Swimming Pool Converted To Greenhouse