DIY Hydronic Floor Heating - Page 7

AC_Hacker · 02-03-11, 01:04 AM

Quote:

Originally Posted by Jay-Cee

...with traffic, heat expansion, contraction, humidity, that floor will bounce and move. There is absolutely no question in my mind about that. The bouncing and shifting of the above flooring from these, even though slight, will probably wear away at the foam board over the course of a few years and turn it into "pink dust"...

Jay Cee,

I definitely see what you're getting at.

Well, the high-density pink foam is fairly dense stuff. I know that it is being used under some of the WarmBoard type of installations.

The way I was envisioning it would be to spread construction adhesive with a pretty fine notched trowel between the layers of foam/mdf(OR OSB)/Winderboard. I figure that would immobilize the structure enough so that it wouldn't start that "working" that you described.

-AC_Hacker

Drake · 02-13-11, 09:32 PM

In the low heat hydronic radiant system I will be using in my new construction project the more I learn about low temp heating the more I think my plan to use heated storage water is not compatible. It is easy to see heating water to 85-90 degrees needed and circulating it thru the floor as needed would work fine. But to use water to store excess available heat via higher water temp is seeming to be less possible for low temp system. Feeding high temp water directly might over heat floor(unless only small volume is feed thru at a time). Added water with a mixing valve couldn't be done if there is no where for the extra water to exit system. And I don't know if a HX can be operated to a specific temp one side and variable on the other.

Drake · 02-14-11, 06:37 PM

Further research has gotten me answer to my question. High water temp storage for low temp radiant heating is ideal. A 3-way mixer before floor loop(hot side) allows cooled loop water to reenter floor loop to "cool" hot side or return to storage tank. Thus no water needs to enter exit system. Did not know mixer could do that(seems there a many kinds of mixers). Now appears that the most economical heat source to get the storage water to temp is next. Sorting theory from economic reality. DIY again seem to offer the best solution. FYI, thermal mass can be added to a structure during an opened wall remodel by filling stud cavity with sand filled recycled alum bev. cans. in non insulated wall. Structure must be able to hold extra load(interior load walls are good) and simple wood raceway can used to space around horz elec runs. Cans stack really well.

pachai · 02-14-11, 11:22 PM

This thread is great - I have read much of it and it's giving me ideas. I'm in a funny situation - I am a DIYer, but with not too much time this year...and I am having an addition built, which will leave me with not a lot of money to do radiant and/or GSHP....

I discussed insulating the slab with my builder, and he reported
that he has another project where he is repairing a slab that collapsed on the styrofoam. So, right or wrong, I am going to let him pour a normal (up to code) slab. (I got to watch the masons today building the foundation walls :-). Note, I am talking about a basement, below the frost line.
When he leaves, I will put down a couple coats of InsulAdd on the floor.

When he asked me what type of heat for the addition, I said Geo. But geo around here is not affordable...and <whatever>. My boiler has a mod so it is now at a 1/12 duty cycle, and that is with current insulation levels. So I can very well afford to extend my boiler into the new space...and postpone the GSHP question till the summer.

But during this construction, I am thinking I can at least put in what a programmer would call "hooks" for future options.
For example, the builder agreed to give me a 6" conduit
to the back yard below the frost line. He said his tractor driver is willing to dig for me to lay ground loop, though I like the drilling idea, and tests looked good....or maybe a hybrid - a long discussion for a different thread.

But for now, framing should start next week.
Hooks that I am considering are....possibly, a pair of pipes to each room for ductless air handlers....(though I could just plan
on basement + attic for retrofit). Multiple pairs of insulated pipes to the attic for other things...like solar thermal.

...and most importantly, radiant pipes.

One possibility is for me to DIY (DIM?)...I saw a blog about this. The floors will be 3/4" tongue-groove. It occurred to me
that I could "notch" the floors for copper pipes. (Perpendicular to the joists). Though that may leave not much subfloor material, I need to learn how thin the radiant pipes can be. I may be able to have him use 1" plywood instead of 3/4" - since the architect originally wrote for 1/2" + 5/8".

(Reading Tube 02005 Refrigeration Copper Tubing 3/8" O.D. x 50' $46 - but maybe too thin.) but...Raiantec says...
Detailed research (DOE) has shown that 7/8" PEX tubing with 0.70" wall thickness and a circuit length of 200 feet is about ideal.

One thing that occorred to me is, what if I have grooves that are rectangular...can the tubing be forced (round peg, squarish hole). Or would that terribly diminish flow rate?

Flooring materials have not been chosen. The first floor addition would be kitchen and eating area; second floor would be Master BR and Master Bath. The old house is hardwood - first floor is HW on top of 2 subfloors of hardwood and planking.

Perhaps staple-up would make sense, even though it is "new" construction.

The main goal for radiant and GS is to eliminate boiler use in the "shoulder seasons" - it was almost 50 degrees in my town today.
I am thinking of all the options for how the water would be heated - solar thermal, etc.

If this sounds disjointed, it's mostly because there are many projects going on at once, and time is going to be tight - but with up to 8KW of solar, this house might end up pretty green.

Thanks
Seth

Drake · 02-15-11, 02:10 PM

A highly energy efficient home does not yet seem to be a complete package yet. At least not economically. Even in "ground up" new construction/design(retro-fit is a hole can of worms). Construction methods/insualtion improv let one build a low energy demand structure. HE windows gather and save passive solar cost effectively. Heat source tech has greatly lowered consumption in several forms. But energy demand is not yet very well matched in heating as I see it. Most EE heat plants are oversized(and very overpriced) for a modest low demand home. Little is saved by the people who are most trying to save. It is very easy to get caught up in the tech and hand out dollars to try and save dimes.

Xringer · 02-15-11, 03:36 PM

Yeah, you have to save a LOT of dimes for some of this stuff.

Spend $2,500 on a Mini-split? That's about 833 gallons of heating oil.

Humm, that's gonna get used up in pretty fast with all the cold weather we get these days..

Of course, in another 2 or 3 years, that 833 gallons of oil might cost $5,000 or more.
I know, it's not going to get a lot cheaper..

Drake · 02-15-11, 05:58 PM

I wasn't implying that non of the tech has merit. One just needs to understand it enough to know whether there will be a real "payback" in it for them. A lot is so new there is little proof it really will out perform its payback life. Some has and is "no brainer". Its unfortunate that manufactures or energy corp have little incentive saving customers money. Use less pay the same. Sorry - OT. I am on the search for the smallest commercial residential W/W heat pump.

Xringer · 02-15-11, 08:10 PM

I'm 65 years old, so looking for 'payback' or break-even isn't something I think about very much.
(Since you can't take it with you)..

When I ordered my Mini-split after much reading and actually seeing the
cooling-only unit at a work site. I read the install manual, check out
the cooling (it was summer) and decided to take a chance.

Heating my home with the Sanyo is an experiment that worked out.
If it dies tomorrow, I'll be looking to replace it ASAP. (But with the latest design).

Drake · 02-15-11, 10:21 PM

To what outside temp do think it works with some efficiency? If I can't justify a full Geo HP system or DIY I am considering a mini-split for shoulder season heating then I would also have some summer cooling. Price and DIY install are getting reasonable. How old is yours? Exterior split should be able to be in attached garage?

Xringer · 02-15-11, 11:39 PM

Quote:

Originally Posted by Drake

To what outside temp do think it works with some efficiency? If I can't justify a full Geo HP system or DIY I am considering a mini-split for shoulder season heating then I would also have some summer cooling. Price and DIY install are getting reasonable. How old is yours? Exterior split should be able to be in attached garage?

All the details (and more than you want to know) are on my project post.

http://ecorenovator.org/forum/geothe...l-project.html

Mine has a bug (or two) and I really have to baby it in colder parts of the winter,
But it's fantastic for cooling.. My wife loves that part..

It's working pretty well right now at 660watts at about 16F outdoors and 70F in here.

I think it depends on the sq feet you are heating. I should have gotten
the 36,000 BTU unit. But the price jump was too much, for what started
off as an experiment.. Live and learn..

02-14-11, 11:22 PM	#64
pachai Renovator-in-planning Join Date: Oct 2010 Location: Northern NJ Posts: 85 Thanks: 6 Thanked 0 Times in 0 Posts	Radiant Floor - construction express coming This thread is great - I have read much of it and it's giving me ideas. I'm in a funny situation - I am a DIYer, but with not too much time this year...and I am having an addition built, which will leave me with not a lot of money to do radiant and/or GSHP.... I discussed insulating the slab with my builder, and he reported that he has another project where he is repairing a slab that collapsed on the styrofoam. So, right or wrong, I am going to let him pour a normal (up to code) slab. (I got to watch the masons today building the foundation walls :-). Note, I am talking about a basement, below the frost line. When he leaves, I will put down a couple coats of InsulAdd on the floor. When he asked me what type of heat for the addition, I said Geo. But geo around here is not affordable...and <whatever>. My boiler has a mod so it is now at a 1/12 duty cycle, and that is with current insulation levels. So I can very well afford to extend my boiler into the new space...and postpone the GSHP question till the summer. But during this construction, I am thinking I can at least put in what a programmer would call "hooks" for future options. For example, the builder agreed to give me a 6" conduit to the back yard below the frost line. He said his tractor driver is willing to dig for me to lay ground loop, though I like the drilling idea, and tests looked good....or maybe a hybrid - a long discussion for a different thread. But for now, framing should start next week. Hooks that I am considering are....possibly, a pair of pipes to each room for ductless air handlers....(though I could just plan on basement + attic for retrofit). Multiple pairs of insulated pipes to the attic for other things...like solar thermal. ...and most importantly, radiant pipes. One possibility is for me to DIY (DIM?)...I saw a blog about this. The floors will be 3/4" tongue-groove. It occurred to me that I could "notch" the floors for copper pipes. (Perpendicular to the joists). Though that may leave not much subfloor material, I need to learn how thin the radiant pipes can be. I may be able to have him use 1" plywood instead of 3/4" - since the architect originally wrote for 1/2" + 5/8". (Reading Tube 02005 Refrigeration Copper Tubing 3/8" O.D. x 50' $46 - but maybe too thin.) but...Raiantec says... Detailed research (DOE) has shown that 7/8" PEX tubing with 0.70" wall thickness and a circuit length of 200 feet is about ideal. One thing that occorred to me is, what if I have grooves that are rectangular...can the tubing be forced (round peg, squarish hole). Or would that terribly diminish flow rate? Flooring materials have not been chosen. The first floor addition would be kitchen and eating area; second floor would be Master BR and Master Bath. The old house is hardwood - first floor is HW on top of 2 subfloors of hardwood and planking. Perhaps staple-up would make sense, even though it is "new" construction. The main goal for radiant and GS is to eliminate boiler use in the "shoulder seasons" - it was almost 50 degrees in my town today. I am thinking of all the options for how the water would be heated - solar thermal, etc. If this sounds disjointed, it's mostly because there are many projects going on at once, and time is going to be tight - but with up to 8KW of solar, this house might end up pretty green. Thanks Seth Last edited by pachai; 02-15-11 at 12:23 AM.. Reason: more detail

02-13-11, 09:32 PM	#62
Drake DIY Guy Join Date: Jan 2011 Location: Mpls,MN Posts: 315 Thanks: 2 Thanked 17 Times in 17 Posts	In the low heat hydronic radiant system I will be using in my new construction project the more I learn about low temp heating the more I think my plan to use heated storage water is not compatible. It is easy to see heating water to 85-90 degrees needed and circulating it thru the floor as needed would work fine. But to use water to store excess available heat via higher water temp is seeming to be less possible for low temp system. Feeding high temp water directly might over heat floor(unless only small volume is feed thru at a time). Added water with a mixing valve couldn't be done if there is no where for the extra water to exit system. And I don't know if a HX can be operated to a specific temp one side and variable on the other.

02-14-11, 06:37 PM	#63
Drake DIY Guy Join Date: Jan 2011 Location: Mpls,MN Posts: 315 Thanks: 2 Thanked 17 Times in 17 Posts	Further research has gotten me answer to my question. High water temp storage for low temp radiant heating is ideal. A 3-way mixer before floor loop(hot side) allows cooled loop water to reenter floor loop to "cool" hot side or return to storage tank. Thus no water needs to enter exit system. Did not know mixer could do that(seems there a many kinds of mixers). Now appears that the most economical heat source to get the storage water to temp is next. Sorting theory from economic reality. DIY again seem to offer the best solution. FYI, thermal mass can be added to a structure during an opened wall remodel by filling stud cavity with sand filled recycled alum bev. cans. in non insulated wall. Structure must be able to hold extra load(interior load walls are good) and simple wood raceway can used to space around horz elec runs. Cans stack really well.

02-15-11, 02:10 PM	#65
Drake DIY Guy Join Date: Jan 2011 Location: Mpls,MN Posts: 315 Thanks: 2 Thanked 17 Times in 17 Posts	A highly energy efficient home does not yet seem to be a complete package yet. At least not economically. Even in "ground up" new construction/design(retro-fit is a hole can of worms). Construction methods/insualtion improv let one build a low energy demand structure. HE windows gather and save passive solar cost effectively. Heat source tech has greatly lowered consumption in several forms. But energy demand is not yet very well matched in heating as I see it. Most EE heat plants are oversized(and very overpriced) for a modest low demand home. Little is saved by the people who are most trying to save. It is very easy to get caught up in the tech and hand out dollars to try and save dimes.

02-15-11, 03:36 PM	#66
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Yeah, you have to save a LOT of dimes for some of this stuff. Spend $2,500 on a Mini-split? That's about 833 gallons of heating oil. Humm, that's gonna get used up in pretty fast with all the cold weather we get these days.. Of course, in another 2 or 3 years, that 833 gallons of oil might cost $5,000 or more. I know, it's not going to get a lot cheaper..

02-15-11, 05:58 PM	#67
Drake DIY Guy Join Date: Jan 2011 Location: Mpls,MN Posts: 315 Thanks: 2 Thanked 17 Times in 17 Posts	I wasn't implying that non of the tech has merit. One just needs to understand it enough to know whether there will be a real "payback" in it for them. A lot is so new there is little proof it really will out perform its payback life. Some has and is "no brainer". Its unfortunate that manufactures or energy corp have little incentive saving customers money. Use less pay the same. Sorry - OT. I am on the search for the smallest commercial residential W/W heat pump.

02-15-11, 08:10 PM	#68
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	I'm 65 years old, so looking for 'payback' or break-even isn't something I think about very much. (Since you can't take it with you).. When I ordered my Mini-split after much reading and actually seeing the cooling-only unit at a work site. I read the install manual, check out the cooling (it was summer) and decided to take a chance. Heating my home with the Sanyo is an experiment that worked out. If it dies tomorrow, I'll be looking to replace it ASAP. (But with the latest design).

02-15-11, 10:21 PM	#69
Drake DIY Guy Join Date: Jan 2011 Location: Mpls,MN Posts: 315 Thanks: 2 Thanked 17 Times in 17 Posts	To what outside temp do think it works with some efficiency? If I can't justify a full Geo HP system or DIY I am considering a mini-split for shoulder season heating then I would also have some summer cooling. Price and DIY install are getting reasonable. How old is yours? Exterior split should be able to be in attached garage?