Greenhouse heating, newbe

14 years ago

We bought a used 6x8 single polycarbonate gh, using it to keep our deck plants alive, palms, ferns, topiary trees, etc. It is full, if this works considering expanding to grow plants. How is the best way to heat,(kind,size,etc) has gravel floor. What kind of thermometer should I use. Do I need to cover gh with plastic for more insulation, if so, what kind and thickness. What temperature should I try to keep gh,any other information you can pass on would be appreciated.

Thanks

Clay

Sort by:Oldest

Comments (9)

randy41_1
14 years ago
I suggest that you use a small electric heater with a built in thermostat. You would have to run power to your greenhouse but it is automatic and you don't have to be home to attend to it and it requires no venting as a gas heater would.
clay_anita99
Original Author
14 years ago
Thank You do you recommend a size.

Clay
Related Discussions
In floor radiant heating in greenhouse
Q
Comments (12)
A lot will depend upon your location/climate. In my area (8300' in the Rockies) we generally get abundant sun. On many days it can be in the teens or single digits outside, and the GH warms up to 70F or more, due solely to the sun. On a 30-40F sunny day it was hitting >100F in the GH before I put in some heat storage. Of course it will cool right back down again after sunset if you don't have heat storage or supplemental heat. And there are always a few stretches without sun in a winter, where supplemental heat would be needed to keep temps above freezing, if that is required for your growing system. In a typical winter, days sunny enough to heat the GH might happen 80% of the time here. Using a SHCS storage system, I am estimating (GH is not fully functional yet) that I can get ~90%+ of my heating costs from the sun. But I am not planning on growing orchids or other tropicals either. It can be a very different situation other places, where the climate is different. Many years ago I was living in the NE. The sunny winter day count was pretty much the reverse of where I am now. This design would not perform as well heating-wise there for obvious reasons (although there are people using SHCS GHs in cloudy climates). That said, there are GH designs for cold climates that could perform well thermally, the pit GH design (and its variations) is one that comes to mind. Another possibility is to attach your GH to your residence. The GH can supply surplus heat during the day to the house and the house can give that back at night. Again how well this works depends upon your climate, land and house location, but designs like this can be very effective (and make getting to the GH in winter very easy). There are several possible different design goals for a winter GH. If you only want some winter greens and other cold tolerant plants, and maybe only in a section of the GH instead of the entire thing, you could design a GH that did that without the costs of heating the whole thing all winter. You could likely still enjoy a warm sunroom on sunny days but not be paying to heat that area on cold nights, with some well planned partitioning. I'm sure others will chime in here. There are quite a few possibilities. Whichever design you choose, you might want to get a good estimate of heating costs, just so that you don't have any unpleasant surprises later on.
...See More
my coal heated 12x24 greenhouse
Q
Comments (20)
If its 18 or 28 degrees out it doesn't seem to get colder in the greenhouse what I mean is it stays between 60 and 70 at night when the stove is going or has the thermal mass heated...I wanted to add some photos of my veggies growing in my greenhouse I will post tomorrow ....and also..my greenhouse is single pane glass on the sides and single layer polycarbonate so I don't have much for insulation but it is totally sealed ...that is very important no nitetime airleaks so in conclusion. Its not bad getting up once in the nite.but to answer you're question if I filled it with coal it could burn 7 hours solid...the stove is 3.5ft deep 2.5ft wide 4 ft tall the stove is in the center of the greenhouse because of the rocks around the stove it helps to heat even
...See More
hobby greenhouse. to heat or not to heat.... that is the question.
Q
Comments (11)
Landmark- An electric heater might work fine, too. Just remember that most small electric heaters use about 1500 watts. Since the standard, home electrical circuit is 14 ga wire, with a 15 amp breaker, it can only handle about 1800 watts without tripping. That means you shouldn't be having anything much else on that particular circuit in order to insure you maintain power to the greenhouse heater. A compromise is to get a dual circuit heater, with switching that lets you use the low power circuit (750 watts), or both circuits (1500 watts total). You could use it on low and also have a heating mat (or two or three), and stay well below the wattage limit for the home wiring. Also, it's good to have an electric heater with a built-in thermostat. You can get a nice, oil-filled, dual circuit, radiant electric heater, with thermostat for about $50-$70: (https://www.amazon.com/gp/aw/d/B000TGDGLU/ref=mp_s_a_1_1?ie=UTF8&qid=1481050429&sr=8-1&pi=SY200_QL40&keywords=delonghi+heater&dpPl=1&dpID=41DId9GtDuL&ref=plSrch) Just remember that using heating mats with domes will be cheaper and more efficient for seedlings because you are only putting heat where you need it. Of course, when the seedling height exceeds the dome height (my high domes are 6" tall), you have to remove the domes, and deal with how warm or cold the air is at that time of year inside the greenhouse.
...See More
Greenhouse heating at night
Q
Comments (8)
I just have a HFGH 10 X 12 so I might not be much help but I use a 30 K BTU Kerosene heater (switching to Natural gas next year). I have 10 (50 gallon) steel barrels painted black filled with water. The sun and/or the heater heats the house and also the barrels. They retain the heat and then dissipate it back to the house during the night. There are formulas online to know how many gallons you need. No need for antifreeze. Just leave a couple of inches of space on the top and cover them. It doesn’t matter if the water freezes because water will still generate BTU’s when it changes from ice back to a liquid. I put plywood on top of the barrels so they serve as my work area bases as well. I monitor the Greenhouse temp, barrel temp and outdoor temp from in my house so I know the barrels are working. It’s not the best solution but it’s free. The cost of the Kerosene does add up but it is cheaper than electricity or propane. Natural gas will cost me less. I wish there was a way for me to avoid the night heater but it is tough here in MA
...See More
randy41_1
14 years ago
I have a similar size greenhouse as you except mine is double glazed with polycarbonate. I use a heater that looks a lot like a Dayton U36 240v Electric Heater. It looks like its about 5600 watts. It requires 220 volts, 30 amps. I would think that would work for you. It is never constantly running here.I start using it in March when the temperature here gets no lower than the low teens. I use this greenhouse for starts only.
dcarch7 d c f l a s h 7 @ y a h o o . c o m
14 years ago
Just for discussion.

In areas that's not too freezing cold most of the time, it is a little more efficient using a heat pump (running an A/C backwards) for heating than reisitance heating.

dcarch
Mike Larkin
14 years ago
Clay anita,
I would buy some poly to cover your GH - It will help. The electic heat is easy, but make sure you are safe. Running an extension cord could be RISKY.
If you are able run electic via conduit into the house - GFI .
Some people also try to cover with bubble rap - solar pool cover - Not sure how much you can save but lots of people try!
Mike
clay_anita99
Original Author
14 years ago
Thank You all for your info and help.

Clay
fuzzymoto
14 years ago
For whatever its worth....this is our first season of covering the grenhouse with a solar pool cover and it has worked VERY well. So far we haven't even turne don our propane heater (only a small electric heater) and our lows have been in the teens & 20's. We're maintaining 50F pretty easily and with the propane on I'm sur we can easily do more. Well worth the cost and already has paid for itself in propane savings.
User
14 years ago
For me, the solar pool cover was a failure. Best results for me with 1" of reflective foil covered foamboard on the north wall, then 4 mil poly clipped to the inside for a 2-6" air layer within the remainder of the GH.
fuzzymoto
14 years ago
Our GH is all-glass and home attached so our north side wall is the wall of our house (and insulated already). Our solar pool cover is on the outside and it completely wraps the greenhouse with no openings or seams. We looked into attaching bubble-wrap or poly on the interior of our GH but given the size and height of the greenhouse and obstacles like irrigation lines, trusses, hanging plants, lighting, heaters, shelves and of course plants, we felt it would have been impossibly difficulty to reliably attach let alone ensure there were no seams or leaks. Wrapping the outside of a box rather than the inside of a box seemed easier and more reliable for our GH. You mileage may vary.

Greenhouse heating, newbe

Comments (9)

randy41_1

clay_anita99
Original Author

Related Discussions

randy41_1

dcarch7 d c f l a s h 7 @ y a h o o . c o m

Mike Larkin

clay_anita99
Original Author

fuzzymoto

User

fuzzymoto

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

Greenhouse heating, newbe

Comments (9)

randy41_1

clay_anita99Original Author

Related Discussions

randy41_1

dcarch7 d c f l a s h 7 @ y a h o o . c o m

Mike Larkin

clay_anita99Original Author

fuzzymoto

User

fuzzymoto

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

clay_anita99
Original Author

clay_anita99
Original Author