Lean-to greenhouse on deck?

Spring City, TN

Rambling thoughts....

I want a greenhouse for jump-starting the growing season -- but nothing overwintered inside, no tropicals or anything like that. Seeds, cuttings, but things going outside for permanent residence in the ground. I'd likely use it as a greenhouse from Feb to after last freeze. But not a year-round growing place.

Even tho I have 5 acers, it's all steep hillside and more than half of it wooded. It would need to be close to the house, which is a story and a half set on a full walk-in basement or I wouldn't use it. And that's the sunniest part of the property as well. The deck on the main floor (kitchen/living room level above the basement) is on the south side of the house and is 8'x24' and has a rail. There is a greenhouse mesh awning there now -- easy to remove as needed.

The 1944 house has little or no insulation. A metal porch roof on the south side would help shade the living room/bedroom on that end of the house, therefore cooling somewhat the entire structure. I have a greenhouse mesh shade awning up there now and it helps but not as much as something solid. A greenhouse would help warm that end of the house in the cool months but would have to have extreme ventilation and fans or the house would be insufferable in the warm months.

Could I have a solid metal roof on a greenhouse and get any practical use out of it?

The clear sides couild be upside down storm windows -- really big ones so when "open" the screen would be on the upperside of the window. If I lined 3 sides with these, I could have massive ventilation as needed. There is one set of stairs on the east side, so it's not really 3-sided, more 2 and a half sided greenhouse if you allow for a door.

Additional problem -- the deck is just an 8'x24' deck with railing, air underneath, but the supports are 2"x12" so there is room for insulation if I could make the decking waterproof, that would be a huge step up for warming the greenhouse but still there would be wind beneath the floor and since the basement door is below the deck, no practical way to completely enclose underneath the deck. Could I get enough of a heat sink with black painted containers lining the south-facing side under planting shelves and insulating all 12 inches of the floor joists -- enough to offset the air flowing underneath in February?

I'm completely baffled about advantages of tempered glass vs. polycarbonate (sp).

I have propane heat in the house, but I don't anticipate leaving the living room exterior door open to the GLASShouse to heat it in the winter.

Anyone tackled a greenhouse on a deck before? A lean-to off a main exterior door? A metal-roofed greenouse? Storm-windows as enclosures? Thanks for any thoughts.

Vandalia, IL

if its just for starts,,why cant u just use a space in the basement,,get some lights and make some inexpensive table stands? i made a glass house,and I use it starting now till spring,,my 13 x 17 costs about $800. BUT i got lucky and someone gave me the windows..and i with alittle help, constructed it my self. it has a tin roof and dirt floor,with heaters ,ceiling fan,thermostat,and vent... good luck dee:)

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Clifton, VA(Zone 7a)

You can certainly build a greenhouse on top of an elevated deck -- that's exactly what I did. Mine is a 5.5' x 12.5' Sunglo model 1500D lean-to greenhouse that sits in the center of a 8' x 30' elevated deck. I built the deck purposely for the greenhouse to provide a level surface on the hilly side yard, and be high enough to catch the sun over the roof of my neighbor's house. I enter the greenhouse through an existing door in the side of my garage, and there are also doors on both ends of the greenhouse to the deck. I installed panels of 2" thick Styrofoam insulation between the joists under the deck like you suggested to insulate against the cold air in the winter. It helps, but the wooden floor is still quite cold, and I've been thinking of adding a thin floor of closed cell foam panels on top of the wood to retain more heat in the winter. I use a small electric heater on a thermostat to keep the GH above 45 degrees in the winter.

I use the greenhouse from October to May. It gets too hot from June to September to grow any veggies inside (90-110 degrees), but that's when I move all the plants out onto the "garden deck". The GH has active ventilation in the form of a thermostatically controlled exhaust fan and intake vent. They work quite well until the temps reach 85+ degrees outside in full sun. I leave both GH doors open all summer long for more ventilation.

If you have a solid wall and door between your house and the GH, I don't think you'd have to worry about the GH heating up the house very much. You could put a partial metal (or shingle) roof over the greenhouse - that's typically done in the design of a south-facing solar greenhouse because it let's more sun in in the winter when the sun is low in the sky and less in the summer when it's high in the sky. Alternatively, you could just get a shade cloth and cover the GH roof in the summer to block some of the sunlight.

Let us know what you decide, and post some pictures!

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Fabens, TX(Zone 8a)

VVM, I sure do like your set up with the 5 gal buckets and storage totes for your tomatoes.

Clifton, VA(Zone 7a)

Quote from Txtea :
VVM, I sure do like your set up with the 5 gal buckets and storage totes for your tomatoes.


Thanks! The eBuckets and EarthTainers are easy to make, and because they are self-watering planters, you don't have to water as often. It costs $4-5 to make an eBucket, but the EarthTainers are a bit pricier -- probably $70-80 including the tall cages. Still, they're big enough to hold two big indeterminate tomato plants that grow 7-8 feet tall. The 5-gallon eBuckets can handle a semi-determinate tomato or compact indeterminate up to 6 feet tall with a sturdy stake in the bucket, so they are far more cost effective. You can find instructions on how to build both of these by googling them.

Fabens, TX(Zone 8a)

VVM, Thank you. I have heard about the eBuckets but never had seen one. Will be checking them out. I one time had a Tomato in a 5 gal bucket and brought it in my enclosed porch, that darn thing produced till the mid of Feb. " If I only had a gerrnhouse" I probley would go crazy. but at this time can only wish.
You take care and thanks for the info

Fleming Island, FL(Zone 9a)

I've been planting in 5 gal buckets (check WalMart bakery for their used frosting containers - these are square) since moving to FL. My plants seems quite happy. I'm going to try the eBucket in the Spring.

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