Hi!
I’m in Colorado which appears to be zone 6a where I am, and am thinking of building a greenhouse. I’m not completely sure on size but it would likely be approximately (10 to 12) x (18 to 20) ft with a small vestibule area. My plan is to turn the back 5 feet or so into a bathroom for pool use, since this’ll be \~20 feet away from our pool, and a small little supply closet area with sink. I may add a door so that plants with special humidity level requirements can be kept in this area rather than the front main greenhouse portion. I posted photos but you can also click this link to see what I’m referring to ([https://imgur.com/a/gI3m4Kj](https://imgur.com/a/gI3m4Kj)).
The greenhouse will be in an empty area with nearly a full day of sun with nothing to block the light. The only area that may be darker would be the back bathroom since it will be on WNW corner but even then it should get decent afternoon light.
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My question is, is there a calculator to determine the potential heating costs? My goal is to be able to use this greenhouse every month and keep citrus trees warm enough during the winter. It doesn’t get too cold here but we have had a few times where it’ll get down to maybe -5 F for a week or so. This isn’t an every year occurrence but I’d like to be able to maintain the temperature in the greenhouse when this happens. I do want to know what it may cost going into the project though so I’m not shocked by some crazy heating bill.
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I was thinking we may do a polycarbonate roof and double glazed windows/doors with the back wall of the greenhouse being either a black paint or putting some sort of tile/rock/stone on the wall to act as a thermal sink. I’d also thought of doing slate or concrete pavers with pea gravel separating the pavers for the floor. If you have any other ideas please share them!
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I’m open to any suggestions. I was thinking we may do a small boiler system with under floor radiant heat. I had an idea to run the the tubing in under the countertop as well with some flexible pex tubing. I’m unsure if this will have any impact but figured it may be able to more directly heat the roots in pots placed on the counter and floor? Maybe if I use metal pots?
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Details about the structure:
Ceiling height: \~9-10 feet. Plan to match our house roof pitch at 45 degrees so that means the ceiling will be \~15-16 feet high at the apex.
Knee wall: \~2 feet but may be higher/lower. Because the placement of the greenhouse is on a slight slope I have half a mind to dig the greenhouse into the dirt so the front is \~1-2 feet off the ground (where the double doors are) and the back (where the bathroom is) would be \~3 feet deep.
Second level (?): I had thought it may be an interesting idea to put a 2nd floor in the middle structure approximately 8 feet off the ground from the main floor. It wouldn’t give much room but would add a roughly 5 feet wide (5.5foot ceiling height at the edges and 8 feet standing height in the middle) area with a pull down ladder. Unsure if this is worth it but it would help to use up some of the space in the warmest area of the greenhouse and could be a good place for plants that need it to be warm. The 4th photo with the red box shows roughly where this elevated structure would be. Ideas appreciated of course!
Water and sewer: Want this to be functioning so the whole area needs to be maintained at a warm enough temperature that we don’t have concerns of freezing pipes. Either that or a way to disable the water/sewer in the winter when the bathroom is less likely to be used since we close the pool when it starts snowing.
https://preview.redd.it/o2nu5h8jjb9c1.png?width=1372&format=png&auto=webp&s=3159e43c1e6a1480caa8e689b05d05cc4c75d102
https://preview.redd.it/q04tah8jjb9c1.png?width=1636&format=png&auto=webp&s=49baa17b766b706341f7c0a972441d8aed72efd8
https://preview.redd.it/ruiz6k8jjb9c1.png?width=3080&format=png&auto=webp&s=f083a49918213ecc846043bc7bda6706f8a1c924
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https://preview.redd.it/g9kkipe8nb9c1.png?width=1636&format=png&auto=webp&s=2fd91cd3c33ac22b8842385c2356bc63d22bed5b
by Bamboozleddicotomy
2 Comments
Its gonna be a hell of a lot with the roof open like that
We had to put up mylar bubble wrap against the walls. It just gets way way too cold.. unless you’re growing some HIGH value plants.. even then if you have forced air heat you’re going to be limited bc most leaves can’t take a heater blowing on them constantly.