Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 09-20-2007, 10:22 PM   #1
Newbie
 
Join Date: Sep 2007
Posts: 25
Rewards Points: 10
Default

Underfloor Heating?


I don't know if this is appropriate for here or the HVAC section...

The house I'm currently in the process of buying has oil furnace, hot water heat through baseboard radiators. Now, I have complete access to the underside of the first floor, which is good, because I definitely have to relocate atleast one baseboard radiator in my kitchen. But...

I thought, now would be the time to look at other options. I remembered a friend who had his home built, and used underfloor heating using hot water, primarily becaue of his allergies. So... can this be retrofit into an old home? We're talking a late 1700's/early 1800's home, wood floors, rubble stone foundation, so on.

Any info would be great - TIA!

CuCullin is offline   Reply With Quote
Old 09-21-2007, 09:26 AM   #2
Member
 
Join Date: Apr 2007
Location: Downeast Maine
Posts: 999
Rewards Points: 500
Default

Underfloor Heating?


Yes. You can install hydronic radiant heating if you have access to the underside of the floors. You run a matrix of tubing between the joists, on the underside of the subfloor, and then back that up with insulation so you are heating the floor, not the basement.

I think it would be set up as a separate zone on your FHW heating system.

NateHanson is offline   Reply With Quote
Old 09-21-2007, 09:42 AM   #3
Member
 
Join Date: Jul 2007
Posts: 1,643
Rewards Points: 1,106
Default

Underfloor Heating?


It might be possible but is not necessarily a slam dunk. Depending on the house insulation and thickness of your wood floors you might have to use a higher temp water than is good for hardwood floors. Have a good radiant heating expert come out and run some numbers. He can tell you what water temps and floor temps are needed. Then you can check out whether your system can generate the water temp needed and whether your hardwood floors can handle the floor temp needed without drying out and cracking.
jogr is offline   Reply With Quote
Old 09-21-2007, 10:11 AM   #4
I have gas!
 
Clutchcargo's Avatar
 
Join Date: Mar 2007
Location: Massachusetts
Posts: 1,781
Rewards Points: 1,014
Default

Underfloor Heating?


The problem with many older houses is that they are not that tight (drafty)and many are not insulated. Before I started my home renovation, the heat loss of my uninsulated and drafty 1925 house were in the neighborhood of 60-70BTUs/hr/sqft.

The hottest you can comfortably run radiant floor heat is so that the floor surface temperature is 85 on design day. That works out to 30-35 BTU/hr/square foot. If your house has higher energy demands, than you will need to suppliment the heat somehow. You could do that by adding radiant ceilings and walls. Actually, you could run higher BTUs in the ceilings than the floor, but you won't get the toasty toe feeling.

The first step is determining the heat loss of your house. Slantfin has a pretty good and free heat loss calculator on their website. It takes a little while to determine all the factors that need to go into the calculation (windows, wall, etc.) but the estimates that it gave me were very close to actual. I know because I installed a temporary heating system through last winter that didn't supply enough BTUs. The indoor temperature was predictable using the outdoor temp.
__________________
I tear things down and build them up.
Clutchcargo is offline   Reply With Quote
Old 09-21-2007, 02:54 PM   #5
Not-So-Newbie
 
Join Date: Aug 2007
Location: Missouri
Posts: 52
Rewards Points: 75
Default

Underfloor Heating?


Hey CuCullin.

Nice handle, I wonder how many people know who that is???
Anyhow, give the guys at Watts Radiant a call, and ask for tech support in Hydronic heat. They will be glad to help you make an informed decision and will even do a heat loss for you- no charge!

800-276-2419
Steven62 is offline   Reply With Quote
Old 09-24-2007, 09:03 AM   #6
Newbie
 
Join Date: Sep 2007
Posts: 25
Rewards Points: 10
Default

Underfloor Heating?


Quote:
Originally Posted by Steven62 View Post
Hey CuCullin.

Nice handle, I wonder how many people know who that is???
Very few notice the reference... the inacurrate spelling is because of the "olden days" of IRC where I had an 8 character limit And thanks!

Quote:
Originally Posted by Steven62 View Post
Anyhow, give the guys at Watts Radiant a call, and ask for tech support in Hydronic heat. They will be glad to help you make an informed decision and will even do a heat loss for you- no charge!

800-276-2419
Great! Will do, the one area that I could really benefit would be my kitchen - its going to be tile over a pumpkin pine floor, and I could really use the wall space for new cabinets!
CuCullin is offline   Reply With Quote
Old 10-14-2007, 02:40 PM   #7
Newbie
 
Join Date: Sep 2007
Posts: 25
Rewards Points: 10
Default

Underfloor Heating?


Bringing this one back up....

After a decent bit of research, here is where I am at. I am going to pull up not just the linoleum on the pine floor, but the pine flooring as well. I'll replace this with a plywood subfloor. On the underside of the subfloor, I'll use pex tubing with channels and aluminum transfer plates, with packed insulation (shiny side up) to keep the heat on the floor side. I'll definitely be going with tile in the kitchen area, so I'll be using ceramic tile for its conductance and storage of heat.

In the other rooms (living room, dining room) I won't bother will underfloor heat - I'll keep the baseboard system. It doesn't impact me as much as the baseboards in the kitchen do (using up my potential cabinet space), and the thermal transfer doesn't seem to be worth the work.

Has anyone had any experiences going with the aluminum transfer plates for underfloor heating? Thanks again for any input :D
CuCullin is offline   Reply With Quote
Old 10-14-2007, 08:45 PM   #8
retired
 
Join Date: Jul 2007
Location: Idaho
Posts: 108
Rewards Points: 75
Default

Underfloor Heating?


Quote:
Originally Posted by CuCullin View Post
Has anyone had any experiences going with the aluminum transfer plates for underfloor heating? Thanks again for any input :D
Check out these forums. You can dig out a lot of discussion about transfer plates on them.

http://www.greenbuildingtalk.com/ They have a radiant group.

http://radnet.groupee.net/eve/forums/a/frm/f/4771065301
dmaceld is offline   Reply With Quote
Old 10-15-2007, 07:29 AM   #9
Member
 
Join Date: Aug 2006
Posts: 190
Rewards Points: 150
Default

Underfloor Heating?


If you are ripping up subfloor, you might consider warmboard instead. Google for it.
scorrpio is offline   Reply With Quote
Old 11-28-2007, 03:39 PM   #10
Not-So-Newbie
 
Join Date: Aug 2007
Location: Missouri
Posts: 52
Rewards Points: 75
Default

Underfloor Heating?


Here at Watts, we use aluminum heat transfer plates. They will increase the efficiency, and are easy to install (over a poured slab for instance, I guess it is relative)!

Steven62 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.