I need advice.

My DH just built a hoop house tha tis 10 ft by 12 ft. It has 1 layer of 6 mm plastic on it. We can get a few frosts here and every few years we get hard freezes that last a few days. I am now obsessed that my hoop house will not be enough to keep my plant safe if we get a good frost. I have quite a few tropicals.
I saw these at HD and was thinking of putting 1 in the greenhouse. They have 2 500 watt halogen bulbs. Does anyone know if that will light up the whole neighborhood in the night(not good) and if it will put out enough heat to make a difference? I also am worried that I could get a shock from it for the hoop house usually has water dripping from the ceiling.

I really thank you for any info you can give me.
thanks

http://www.cornerhardware.com/hardware/iteminfo.html?action=iteminfo&item=090529450219&cat_id=1650

i had a 12 by 12 ft covered with 6ml plastic. i used a space heater electric sitting on a chair in the greenhouse and it worked just fine. even on the nights the temps hit the teens. i never got shocked or anything. the heater i bought was on that does not have the red glowing coils in it. it was a titan and fan forced. got it from wal mart.
hope this helps

Yes, that little heater is like one I use, and it will heat a 12x16 space with one layer of 6mil plastic, where the ceiling is almost 10 feet high. Once the heat builds up, it stays nice and toasty if the floor is gravel or concrete. You do need to give it a head start during the day so it can be warm before the temps drop to the nighttime lows. I would not feel good about setting it on bare ground, but if your floor is not that, it should be fine. Otherwise, the chair idea is great. I have read stories about the halogens exploding, so it might not be as safe as the little heater.

I got a 1500 watt electric heater, fan forced, with thermostat, to use while I'm looking for a used Modine natural gas heat blower w/vent that I can afford. I also circulate air from the house through the greenhouse to help out. I keep the heater set at 75, and it chugs it's little heart out -- the little engine that could -- but it stays around 68.

The GH is fiberglass layered internally with 6 mil plastic for insulation. It's also built on a concrete floor with one wall being the 2'-thick brick wall of the house and the opposite wall is a rock retainer wall with a mountain behind it. So, three of the six sides are some form of rock, and it is still nearly impossible to get it to 70, which is important because I'm trying to grow tropicals, not just keep them alive for the winter.

With a small GH, circulating the air from a heated house through it is a super easy solution. If the GH is not against your house, ductwork is cheap or, even less expensively, you can get a soft plastic duct (about a foot in diameter) to run to and from the house, with a little inducing fan.

The investment is minimal, except for the heat bill, which varies, of course, with the climate. You can put the fan on a thermostat and maintain whatever temp you want, up to around 60.

Another thing people with hoop houses are doing to keep heat in is putting on a second layer of plastic and attaching a little fan (they make them especially for this) to blow air between the layers of plastic, inflating it to create a layer of insulating still air. They say it cuts down on the cost of heating a lot.

Kell, I have a suggestion...ask Liz from the Brugs forum!! Elaine

kell,before I got my funace put in I used one of those little ceramic electic heater and it kept it reasonably warm in there.....
My electic bill was outa contol,but the brugs were warm....

SO it is OK to buy just a regular little heater and stick it on a chair and have water drip on it from above???

I had foil over it

Kell - I have 2 1000 watt high pressure sodium bulbs hardwired into the GH. I also have a small oil-filled heater. I turn the heater on low during the night and have the lights on during the day. And yes they will light up the neighborhood - that's why I only run them during the day. I have also had the Harbor Patrol boats circling around in front of my house with their binoculars trained on the GH. It's a tradeoff - you don't want to tick off your neighbors but you don't want to completely shade out the lights or the police will think it's a grow-op.
The lights will put out a fair bit of heat.

Well then, I guess the lights then will not work here as I just need some heat at night if we get a freeze. Planter Riks is so far beyond me here............... unfortuately we are talking a temporary little hoop house. I wish I had better........but I am glad my Dh let me have this.

My neighbors are very close to me. so the lights are out. Maybe I should do what JCF was so kind to share with me................ and put silver foil over it.

It is just so wet in there, I am afraid of electricity in it.

maybe you could try a couple of kero-sun style heaters i have 2 in mine along with an electric and a big furnice. the furnice uses abut $7 in kero a day that is why i have the 2 smaller ones because they don't have a chiminy and all the heat stayes inside and the furnice does not run as much. you can sometimes find these at yard sales and flea markets at reasonable prices. and a bit of advice use the clear kero if you can find it not the red dyed stuff. when i was useing the res stuff i would have to replace the wicks on the kero-sun style and clean the furnice all the time. i watched the guy come and clean it enough that i i can do it my self now and save $75 when it needs cleaned and i can do it faster than he did

oh nad the halogen that yo likked to... i don't think they put off enough heat for what you want i have a couple of them that i use for light and when they are on they light up the GH nicly but not the whole yard and the GH looks cool at night from the out side with the glow from inside

This message was edited Sunday, Dec 8th 9:51 AM

If your GH drips a lot of condensation, I agree that an electric heater could be a danger. Not so much for getting electricuted (a decent one will go off immediately if there is a power surge or if it is tipped), but because it could short out at night or when you're not around.

My GH has a slant roof, so it doesn't drip at all. I guess the water runs down to the wall ... which would explain why there are always ferns growing between the rocks (never thought about it). I would have thought that roof condensation in a hoop house would run either direction, rather than drip.

If you want to use an electric heater as an interim measure (like I am) while sorting out the best permanent solution, I'd suggest putting on something raised off the floor. I cut up wooden warehouse palettes to put under all the GH benches so things stored there would not be on the floor. I would also build something more secure than foil to keep water off of it -- like a little lean-to type roof. It shouldn't take more than a few minutes to knock together and tack plastic on the top of it.

We had many discussions about free-standing oil/kerosene/gas heaters. I wouldn't use kerosene because the fumes are so awful, and I can imagine that it wouldn't be great for the plants either. When I raised animals, I found it completely inhumane when I visited another facility that used kerosene heat, and I could hardly breath -- imagine the small animals with more sensitive respiratory systems who couldn't escape it!

But the greater concern about any form of freestanding oil, etc., type heater is that it burns up oxygen and gives off carbon monoxide, fatal to humans, and not good for plants (carbon dioxide is the stuff plants like). That is also why I am building a lean-to beside the GH for the generator. There was a story in the news today about an elderly man in NC (where there is a cold wave and a big electricity black out) who died from asphixiation because he had a generator running on an enclosed porch.

Any unvented oil (etc.) burning heater that isn't fan-forced could also send heat straight up to make its own vent in a plastic covered GH.

So do you guys think if you use an elec heater in a greenhouse that does drip alot, if the heater is protected in some way that it would be ok???? mines hooped at top but I always have water dripping off the top at certain times. DH thinks with the heater going that it won't drip as much, but this concerns me??? Shoudl I try to put something over the top to keep the water from dripping on it?

Katrina

Ground Fault Interupter (GFI). It comes on all outlets that have the little red "re-set" switch on them. Really a neccessary thing if you have electricity outside the house. They are required in a lot of new construction now, anyway. Could save your life, too.

as cold as it is right now i have 2 kero heaters to augment the furnice. I make sure the flame is not to high and i have no trouble with fumes. also my GH is FAR from air tight.