cheap amazon/ebay underfloor heating?

[Psychedeliam]

Is anyone currently using a cheap underfloor heating kit from amazon/ebay, how is it ? I can't get away with blower heaters or oil rads as the landlady is a ballbuster about electrical bills so im focusing on keeping the roots happy and going from there.
I'm not so much worried about the temps as much as i am them being a safety hazard.
currently deciding between a 150w/m2 UFH kit, a dreamland intelliheat electric blanket or soil heating cables and need to get one or the other ASAP

 

[smokinrav]

Electric is electric, it doesn't matter how you try to get around it. Heating with electricity will cost money.
You might want to just try to offer the landlord extra cash to deal with your cold sensitivity that you just developed. Wink wink

 

[J232]

I did quick stoner math and came up with about $0.50 a day @ 150 watts and .14 cents per kwatt. That would be assuming it drew 150 watts 24/7. I know nothing about the other stuff you mentioned other then a heating blanket, I used a oil heater and raised the pots to allow air under them. Safety, imo anything electrical that flexes, moves around a lot, like a blanket will be a bigger “risk”, bending wire can cause fatigue, poorly made devices can use cheap wire. How many time did you wonder if grandmas 45 year old electric blanket would torch the next person to use it

 

[Psychedeliam]

Electric is electric, it doesn't matter how you try to get around it. Heating with electricity will cost money.
You might want to just try to offer the landlord extra cash to deal with your cold sensitivity that you just developed. Wink wink

Oh totally, my thinking is going for power efficiency, an insulation board and some tiles from the shed with 150w of underfloor heating on a thermostat and probe in soil is probably much better for the plants than an = heat source like a single small tube/aquarium heater being in the tent

I did quick stoner math and came up with about $0.50 a day @ 150 watts and .14 cents per kwatt. That would be assuming it drew 150 watts 24/7. How many time did you wonder if grandmas 45 year old electric blanket would torch the next person to use it

That sounds about right, i'm in £ but its pretty much 1:1 on the quick math. Ill have it on a thermostat and probe in the soil so i imagine it would be on 6~ hours a day; the ambient temp is 23-25 in the day already. Those old electric blankets are terrifying

 

[NewGrower2011]

I was in a similar spot and looked at those soil cables, but I ended up just getting 2 of the 2x4 seedling mats to go under my trays as I was concerned about my temp drop with light-off and like you wanted to focus on keeping the roots happy. I was covering a 4x4 area with smart pots that were sitting in Rubbermaid bus tubs for my trays.

Actually ended up not using them - as I switched to SIPs on that run and I wasn't quite sure if I wanted to heat the rez that way and let it radiate up into the tubs. The rez itself is somewhat of a heat sink and should retain and radiate some heat at least for the 1st part of lights-off. Have been on the fence since then about that combination. If I switch back to pots in a tray, I'd definitely consider running them with a temp probe.

 

[NewGrower2011]

Other considerations I was thinking of, but didn't focus on, was how efficient is the setup? I'm guessing those seedling mats aren't exactly designed for efficiency. And how many degrees can it raise things? I.e. I'm guessing those soil cables may be more capable/higher wattage, etc. I'd absolutely make sure any setup included a temperature probe/controller.

 

[Kerovan]

Sounds like maybe you shouldn't be growing there if you are renting and trying to hide it from the property owner. As for heating, generally the oil filled radiators are the most efficient.

 

[Herb & Suds]

Other considerations I was thinking of, but didn't focus on, was how efficient is the setup? I'm guessing those seedling mats aren't exactly designed for efficiency. And how many degrees can it raise things? I.e. I'm guessing those soil cables may be more capable/higher wattage, etc. I'd absolutely make sure any setup included a temperature probe/controller.

Mine don't increase room temp
in fact they could use even a stronger heating element
I have 2 two by four foot heat pads and I can't imagine them working in an unheated situation though

 

[Psychedeliam]

Sounds like maybe you shouldn't be growing there if you are renting and trying to hide it from the property owner. As for heating, generally the oil filled radiators are the most efficient.

She has no problems with it being here, just tight on money and i don't pay bills in my tenancy agreement so i'm trying to keep it efficient for the longrun.
Ill come back with an update in a few days, ordered one, added a switched fuse spur to run it and got the stat ready but the under-tile kit i ordered was a hassle to lay non-permanently so i ordered an under-laminate mat today. This way i can just put down some laminate boards, then the insulation board, the mat, then more laminated boards, glue and screwl it all together and its still very light when i choose to move or upgrade.
Overall happy with the kit though, the stat is decent and sturdy, materials all seem good quality, came with a lifetime warranty if i where to register a sparky minor works cert# which is promising!