underfloor heating?

[webby23]

hello gang, may I pick your knowledgable brains please?

Did anyone see the victorian farm prog last night where they built a new pig sty and laid loads of glass bottles under the concrete floor to act as 'storage radiators' and help keep the pigs snug through the winter?

I am just at the stage of preparing a base ready for my super new rhino g/h and wondered if I could use the same technique, laying bottles in a bed of sand and topping off with slabs (in the areas where I'm not having beds
Any thoughts would be very welcome. Thanks, Lynda

[scooby]

probably wont help your green house heat wise but might not make your feet as cold when standing on the slabs

[lynda66]

no idea, but ..... you are cool, cos you spell your name proper ...... welcome to the vine xx

[terrier]

I would have thought that filling the concrete base with glass bottles would seriously weaken the concrete, but maybe not, I'm not an engineer. You would do as well to line the concrete bass with black plastic. That would heat up the concrete (and the air in the glass bottles) and assuming you've laid a polystyrene and reflective shield under the concrete, would stabilize the temperature a bit in the greenhouse. You go first and let us know the results and welcome to the forum.

[burnie]

Heat and conversly cold , transmit by conduction,convection and radiation,therefore I think the bottles were an attempt to interupt the conduction bit,like the vacuum in a flask but not quite so effective.If you were trying to stop radiation then the reflective surface should face downwards? as for convection then you need to trap a layer of air(bottles again?)or fleece on top.The science is at best on shakey foundations(could be the bottles again)and the application of it is,what if you want to move your greenhouse,you've got all that glass buried under there.
p.s on the up side there's a lot of wine to be drunk

[webby23]

thanks for the input everyone, it's suddenly looking a lot more complicated!!

It's a 16x8 gh so I don't think it will be moving in the near future! It will stand on a concrete filled trench for stability and I had decided sand and slabs for the inside flooring so there was the option to add another bed or planting pit later and somewhere for excess water to drain away. I just want to get growing but don't want to do it all wrong. Maybe I'll just have a glass of wine and think about it a bit more - cheers! Lynda