In reply to A newbie all over again! by Annec
In reply to A newbie all over again! by Annec
[quote=Torchiarolan;119467]Hi Pilchard,
You will save and retain an awful lot more heat in the house by insulating below the grid, than you will ever gain in several lifetimes[B] from[/B] an uninsulated floor under the grid.[/quote]
Yes, I know Torchie. But not using that free additional heat goes against my grain. If I could be presented with figures showing that the value of that additional heat amounts to no more than than a pint or two of Guiness per week then maybe I'd stop worrying.
How much is Guiness these days anyway?
Pilch
In reply to A newbie all over again! by Annec
Pilchard - there are two trains of thought which will have to be compromised on...
1. Accumulating energi in the concrete slab above the insulation which is less responsive or...
2. Having no floor screed depth at all to have a responsive system that can react quickly to change.
Naturally the compromise is as little screed thickness as possible.
As usual my opinion includes lots of insulation of at least 12 cm of insulation under the floor pipes.
One consideration to take into account is the heat losses of the existing structure. If it has no insulation, lots of thermal bridges and poor windows then the heat losses maybe bigger than the amount a low energi system can deliver to the rooms and house. Forcing you to install additional rads and destroying the whole idea with accumulators and heat pumps. Which work best on low heat systems (27ºc-36ºc) Rads are at between 45ºc - 65ºc.
What ever you do I would recommend that you talk to a thermal heating engineer and do a check using legge 10 even though you might not need it for the improvements.:smile:
In reply to A newbie all over again! by Annec
Think you will find Pilch that due to the layout of underfloor systems, then you need the insulated layer. Of course you can go to the minimum recommended thickness. The main thing though is to heat the actual floor that you are walking on and with a minimum insulation level there would still be some, but little, ground heat coming through. Ground heat, depending on soil type and humidity, is fairly constant from around 1.2 to 1.5 mtrs in depth. I have temperatures at the moment of approx 11C at 1.4 mtrs, but in the coldest winter this dropped to 4C.
That would increase the heating requirement for the house as you would be losing a great deal through the uninsulated floor. If they dont want to insulate the floor, then they could always go for wall panels ... although more expensive.
Hope this helps.
As Torch says, why heat the ground at the same time as the room. Think it would cost a lot, more likely a couple of pints of Guiness per day than a week.
In reply to A newbie all over again! by Annec
"moved to italiauncovered.co.uk"
heat from the ground?
Submitted by Anonymous (not verified) on Sun, 05/03/2009 - 08:01In reply to A newbie all over again! by Annec
[quote=pilchard;119464]Am hoping for a response from Geotherm on this one but anyone with an opinion is welcome.
Have a freind with a farmhouse in Abruzzo that wants to convert the ground floor into kitchen, dinner & lounge. He is a fan, as I am, of underfloor heating & wants to instal it. I have never installed one nor even thought about installing one so I'm in the dark on the next logical conundrum.
In the UK the floor would be insulated to stop the system wasting energy heating up the ground under the house. Here in central Italy the ground floor of the house is actually the warmest part in winter due to the ground heat effect. If the floor were insulated prior to laying the grid then this ground heat effect would be blocked.
What say you all?
Pilch:eerr:[/quote]
To answer your question directly: The temperature of your floor when heated with water applied at some 35c will be hotter than the ground, so the flow of heat will be [B]towards the ground[/B] regardless of how much potential energy the ground has stored. Therefore to slow down this energy leak you must have max insulation. Tell your friends to stick in an oversized stufa with back boiler and a large heat store (if they haven't already) and they will be well on the way to slashing their heating costs.
In reply to A newbie all over again! by Annec
[quote=pilchard;119464]............Have a friend with a farmhouse in Abruzzo that wants to convert the ground floor into kitchen, dinner & lounge. He is a fan, as I am, of underfloor heating & wants to install it. ........:[/quote]
Don't forget to remind him that there is a minimum ceiling height required for a habitable room - It is 2.7m
See the old thread [url]http://www.italymag.co.uk/forums/building-renovation/9003-cantina-planning.html[/url] for info.
So he may have to dig down to achieve adequate insulation value, rather than just raising the floor levels.
.
"moved to italiauncovered.co.uk"