Hello folks,
I am beginning the process of restoring and remodeling a two-story 3br/2ba farmhouse built in 1900. My wife and I will be moving into it. (It’s been in the family since new, was maintained by my father until he died, fell into some disrepair over the last ten years, and now it’s my turn).
So, I’m gonna be asking a lot of bonehead questions, please bear with me.
Not surprisingly, the house is an energy sink and its oil-fired central heat system, though updated in the early 90’s, only heats some of the first floor. I like the idea of radiant floor heat and, as the upstairs (8ft.x8ft.) bathroom (and most of the plumbing and fixtures) are pretty much shot, this seems like a good time to install such a floor in that room.
In the long run, I’d like to install propane-fired radiant floor heat in the Kitchen/enclosed back porch (which has no heat vents to speak of now), as well as one of the upstairs bedrooms.
My plumbing skills are pretty good and FHB (and a search of old posts here) seems to suggest that, aside from the question of sizing and boiler installation, the installation of a hydronic heat system is within the skills of a jack of all trades/master of none DIY guy like me. (I realize you don’t know me at all, but again, bear with me.)
So my questions are:
Is the running of pex and manifolding and everything short of the boiler really DIY-doable? Does that really save much money vs. letting an HVAC guy do the whole thing?
Can this be merged with a propane-fired hot water heater?
What’s the best written guide to such an undertaking? (Beside youse guys.)
Are there any special considerations/suggestions for using such heat in an old house?
BTW, I am beginning the process by getting an energy audit/blower test. I expect that it will not be a pretty infra-red picture. The recent FHB article about energy remodeling of such houses looks like it will be my overall guide.
Thanks for any and all advice,
Jasper57
Replies
Jasper:
I think that it is quite doable, as I did it!. My house is two floors with a combination of existing and new construction. I used the Warmboard product for the sub-floors and had control board fabricated. I am very please and comfortable! I'm guessing that I saved about 50% on the controls over having it built locally. I also believe that it is more likely than not a far superior system than I would have installed had I used the HVAC companies that are in my area.
I used the company below for the control board and cannot say enough positive things about them. I heard about them through the this sub-forum and the participation of NRTRob. His responses seemed well thought out, informative and very professional.
Northeast Radiant Technology, LLC
26 Winter Street
Gardiner, ME, 04345
ph 207.582.8721
fax 207.582.8755
http://www.nrtradiant.com
Edited 10/22/2008 4:32 pm by homohabilis
Warm board is awesome stuff, pricey, but well worth it.
Can you explain how you handled putting warmboard over your existing subfloor because warmboard is supposed to be the subfloor as well. Is it better, worse, or about the same if you do the warmboard over subflooring?
Josh:
The house was built in 1936, kind of an "Arts & Farts" style. The original part of the house never had a finished floor, just the 1x8 T&G sub-floor over the joists. I stripped off the vinyl kitchen and bath floors and placed the Warmboard directly over the original T&G. The foundation, sill/joist of the new construction was adjusted "up" to match the sub-floor height of the old. The new construction just uses Warmboard as the sub-floor so it matches that of the old part of the house and all lines up.
The only place that one can sort of tell is that the front door threshold (original part of the house) is about an extra inch high. The existing interior doors, there were only 3, were re-framed since the interior was mostly gutted and walls moved around. I'm probably the only one that notices the front door, but that's the kind of guy I am!
Thanks for the reply, Homohabilis. How much was the warmboard and pex per square foot? And, if you don't mind me asking, what was the overall cost of the system for how many square feet overall? I'm just trying to get some rough idea so I can evaluate any quotes I get.
Jasper57
Borrow the book "Modern Hydronic Heating For Residential and Light Commercial Buildings" by John Siegenthaler. I've been investigating radiant heat too and this book seems to be the authoritative source. I say borrow from the library because they don't give this one away. It's something like $170 although I've seen it used on amazon.com for $100. I think that's where I'll buy it. It's an incredible book.
I did my own. I used Wirsbo manifolds w/ balancing valves. Cast brass. expensive, but definately nice. Also got the Wirsbo heating guide to give you some ideas about systems, layout, configuration, etc.
I made my own 'warm board'. I got a deal on 3/4" plywood used (and clean). I ripped e.g. 8" wide strips at like a 10 degree angle. I used a inside/outside radius template for the switchbacks. We bought the aluminum panels and spaced them out along the run (alternating them in the adjacent rows). My wife and I laid it out. Screwed the plywood down w/ square drive screws (also purchased at a 'rebuild it' center). Laid out the tubing and wedged the next plywood strip against it. The 10 degree angle was perfect to hold the tubing in place. The 'normal'/straight runs were pretty easy to laydown. A lot of detail cutting when it came to some of the odd situations (which we had a fair amount of), but still doable and way cheaper than warmboard. I had some luck in getting inexpensive materials.
I laid out my system graphically. I ensured my loops were roughly the same length to avoid heating disparity.
Thanks for the reply, Clewless1.
After HH's reply, I called Warmboard. They spent a generous amount of time on the phone with me. Indeed they are not cheap ($6.99/sf for just the board). but they are service-oriented and I like that. They only sell factory direct, BTW.
The sizing calculations are no small issue as you have to figure in the ceiling height, coldest day, insulation, "CO2 analysis", etc., etc.. So "you gotta getta guy" for that. They gave me the name of a local guy that they work with. Apparently this guy is willing to let the homeowner do as much as he can handle, so that's cool.
Shipping cost is pretty high because the 4x8 sheets weigh nearly 100 lbs. each. That had me leaning toward doing a bigger job than I had initially planned (or could afford). But, Clewless1, your idea of making homemade warmboard might work out better for the upstairs bathroom I was planning to do as a "test" so I appreciate that. Due to some damage, I have to replace the floor in that bathroom sooner rather than later.
In the long run, I am basically looking at heating 750 sf of this house by hydronics so that suggests (according to the Warmboard guys) that it might be possible to do it with one or two propane water heaters vs. a condensing boiler. All that depends on the calculations, but it's interesting.
I'm psyched,
Jasper57
Good article on using a water heater as a heat source here at JLC.
http://www.jlconline.com/cgi-bin/jlconline.storefront/490097ea02396dc727170a32100a0604/UserTemplate/82?s=490097ea02396dc727170a32100a0604&c=ea26d15040a43532d4a9669d18125128&p=1
Joe H
Jasper:
The house, about 2.600 sq. ft., is located in the Napa Valley in California. The construction started in about 2002. I'm guessing that the decision to use hydronic heating was, in total, about a $10,000 over a traditional forced air system. I chose hydronic for two reasons. The first is that I really dislike forced air and never really found it comfortable. The second is that the house has a fair number of windows and I was able to get some energy "credits" using hydronic to meet the Title 24 Energy requirement of California.
My contractor stated that it would add about $3,000 to use the Warmboard over traditional plywood sub-flooring. He thought that it would be good experience for him so I'm guessing that he "ate" some of the costs somewhere. Shipping was relatively insignificant since Warmboard in located about 150 miles away and there is a local supplier about 25 miles away. The gas water heater is a Polaris - American Water Heater, that provides both domestic and hydronic heat that cost close to $2,000. The pex-al-pex is Wirsbro/Uponor and with fittings and shipping was about $1,500. The control board, valves, manifolds, pumps, heat exchanger, etc. is from NRT as I stated and was about $4,000.
I've been very lucky that all of the suppliers, trades and subs have been very helpful, I don't believe that I've been hosed once by anybody and I am one happy and comfortable camper!
Homohabilis,
There is a Warmboard warehouse in Wilkes-Barre, PA. which is not too far away, but shipping just a couple of sheets costs as much as shipping a larger number, so that's an issue I'll have to deal with.
I don't have anything against forced air, and I guess I could find a way to run ductwork into the areas I'm working on, but I like the idea of having more than one type of heat in case one type of fuel goes up in price or becomes scarce. Also, of course, it is possible to add solar water heating to a hydronic system at some point, if and when it makes sense for us. I like that.
Thanks again,
Jasper57
Thanks, Joe. That is great information. The Warmboard guy is doing his own remodel and he went with a Bradford-White GS-2-25SBN gas water heater. I expect that the water heater in our house is shot, so it makes sense to replace it with one that might handle both jobs.
Jasper57
Yeah ... $6 and change per sqft. I think I paid like $14 per sheet (if that). I did almost my hole house w/ a unit I bought at the used building materials center (about 1400 sqft I think) ... cost me like $350. I had to buy a handfull of new sheets to finish the job. Not sure what AC plywood costs ... guessing $25-30 per sheet.
Never really heard of anyone 'sizing' a system ... at least the tubing. The boiler, yes, but even then ... hold your thumb up. Kidding a little. I don't advocate that ... although I pretty much did that in my house (although I'm no stranger to sizing, so my educated guess is probably w/in 15%).
The major key in cutting your own warm board is a template for both the outside and the inside radius. I think for 1/2" ID tubing, I ended up w/ like 1/2" gap at the top so my spacing/dimensions used that. But cut a sample out of scrap and then put a piece of tubing in and measure your difference. The inside radius template is a no brainer ... a piece of straight w/ the radius. The outside radius, you need to special cut and make sure it is right, otherwise it will screw up your rows. It is shaped like a U.
Find a supplier of the aluminum plates. There is a fairly big range of cost here ... I found some at like 1/2 the cost of some others ... shop around a little. You install them as you put the plywood down ... slightly tricky ... but really pretty easy. You can do it.
I put hardiboard (1/4" I think) over the plywood in my bath and then tiled over that.
I did DIY rfh in my house when I built back in '95.3/4" subfloor over TJIs. I did staple-up from below. Then friction fit 1/2" foil-faced polyiso up against the staples. On top of the 3/4" subfloor I have 1/2" ply then brazilian cherry flooring.Works great. Oil-fired boiler, have a mixing valve to take the temp down to 110 degrees for the closed system rfh.I have one manifold for the upstairs, one for the downstairs, 10 loops down and 8 loops up, all loops are pretty similar in length.Each loop has a flow valve, so I can adjust the flow through each loop. I tweaked things the first year and haven;t touched them since.Works great, whole house warmth, no cold spots, yadda yadda yadda.
You've gotten good advice thus far you can safely follow it and achieve what you want or do a little research on the subject and see what else there is.. There's a guy who posts here regularly who's extremely helpful..
His name is NRTRob.
I've never found him to lead anyone astray..
I did things a little differant because I had easy access to the bottom of my floor..
Instead of putting my pex on top I put it underneath. (fairly common) I held my pex up with aluminum flashing because it went up so easy. Transfers heat out well and was much cheaper than other systems..
You could also put your tubing on top of the sub flooring and pour litewieght gypcrete over it.. that will get you a level floor to work off of and transfer heat well too..
you can either buy manifolds already set up or make your own .. while you will save a little bit of money making your own. it does require some real skills..
Finally if you are using the in floor radiant for such a small area look into water heaters as your "boiler" My 5500 sq.ft. house with 76 windows in it uses them and the floors are nice and warm.
On the other hand I have a super insulated home .
Insulation is the real key to long term efficency.
Some is good, more is better and too much just saves more money <grin>
The best insulation is Foam. There are those who have an interest in other systems and they will advocate theirs. However I have no such interest..
I looked and foam is an energy saver over fiberglas or celluliose. It has other benefits as well.
Good thought, Frenchy. I guess I should look into nailing tubing direct to the existing subflooring. Any more details or warnings you could offer about that approach would be appreciated. Most of the areas involved on the first floor are accessible from underneath.
Insulation is the first order of business for this house, though I would have to hold off in the kitchen/back porch area if I went with an underfloor approach like you used. The floor is not quite level between those two rooms so it's tempting to go the gypcrete route but I've seen videos of that process and it's scary to imagine what happens if the gypcrete sets up too fast.
Thanks for your reply,
Jasper57
OK sure, a few details in no particular order. I used roofing nails to hold up the aluminum flashing but I have 2 inch thick subflooring so 1 1/4 nails wouldn't go through. if your subflooring isn't that thick you might cheat and use lath or wooden stakes nailed up to hold the flashing in place. My Brother in law simply stapled his up and it seems to be holding just fine.
Where the edge of the flashing runs over the pex, Take a round philips head screw driver and slightly curl the edge up so it won't chaff against the pex as it shrinks and expands from the heat cycles..
If you have concerns about too much heat radiated down (it will want to go down first) you can seal off the bay with foil backed foam insulation. Install foil up, foil to flashing . That causes heat to radiate up and allows a minimum of heat to radiate down past the insulation.. I use the thin 1/2 stuff and slice it with sharp utility knife. I make it about 1/4 inch wider so I can just shove it up and have a good friction fit. If you are a belt and suspenders kinda guy (I am) spray the edges with a can of great stuff and that will effectively "glue" the insulation in place..
They make retarders for concrete so it doesn't go off too fast, they also sell a self leveling additive that really works..
I'll add another endorsement for NRT. We used them to design the system, and found them very helpful. The site is: http://www.nrtradiant.com/linksPutting the PEX etc in yourself is very doable, but can be a lot of work, depending on how much insulating you have to do, whether you are crawling around in a tight crawl space, etc.
A couple learning points from my own DIY install:
If your loops are about the same length and all parts of the home are roughly equally insulated, don't bother with expensive flow-balancing manifolds. Shut-off valves, sure, but the manifolds and balancing flowmeters are an unnecessary expense- IF the loops are roughly the same length!.
If you go "staple up" from under your subfloor, go with the panels that the tubing snaps into. They're not cheap, but they work really well- meaning you get a warm floor at lower water recirc temperatures. Depending on your heat source, that may or may not give you more thermal efficiency, but regardless it does make the heating more even.
If you're going with wood flooring on top, DON'T do staple-up. Build the tubing into the subfloor to get the emitter closer to your feet!
Everywhere we have tubing in a concrete slab, the floors are WONDERFUL!
Warmboard sounds great but VERY expensive. Way out of my price range.
Weil-McLean amongst others give away copies of their sizing/heatloss calc software. I used it and it worked out just fine.
As to energy savings: insulation and air leakage control give you a far bigger bang for your buck than radiant does on its own. We did manage to heat twice the combined addition/old house floor area for 20% less energy than it took to heat the old house, but that was mostly because we replaced an ancient coal thermosiphon boiler w/gas "conversion" burner with a modern modulating, condensing boiler. Eliminating a long, uninsulated wall and a couple of drafty knee-wall closets with a super-insulated addition didn't hurt, but MAN, I LOVE my Munchkin boiler!
I wouldn't use a conventional tanked hot water heater as the heat source- they're far too inefficient.
Best of luck to you!
I have just finished putting in the pex tubing for my infloor system and can say that it is do-able.
I looked into using warmboard but decided to use a 1 1/2 inch concrete over-pour instead. I used the leftover material from my footing forms to raise my wall plates, nailed down the pex with talon clips and I 'm ready to pour. The concrete will cost $1200 so I figure I'm ahead that way.
As far as the rest of the system is concerned ( ground sourse heat pump, six holes drilled 200 feet deep, manifold, etc), I have hired a pro.
This doesn't really relate to how to install, but one thing I've noticed upstairs is: We have three lines running to the upstairs. I wish I had marked them during installation, as it took me a while to figure out which one to cut back, so that the bedroom would be cooler, and th bathroom hotter. At first they were all flowing at the same speed, and the bedroom was too warm
I leave the thermostat on 75 all winter long, as it takes too long to heat up and cool down, so I don't set back at night. (We're running the hot water off the outside wood furnace, with wood from the farm. Finally, I can be as warm as I want!)
A bedroom...in a farmhouse...that is "too warm"...what a concept!
Jasper57
A little explanation is in order. Our part of the house is built onto the back of my Mother's. So it was built with foam insulation, a little better than the rest of the house. To heat her side, my brothers took out the oil and wood burners in the f/a furnace, and installed a radiator, that is hooked into the boiler.
So the; outdoor wood furnace heats our floors with radiant, hers with f/a and domestic hot water for both. We still have the oil burner for the hot water, if we needed to shut down the furnace.
As I said, i leave that thermostat at 75. If it gets to hot, I open a window.
I saw a few of those outdoor furnaces up in Minnesota this Summer. Is that where you are?
I grew up in the house that I'm now working on. Back then, no heat on the second floor, oak-framed storm windows that rattled in the frames. Not a bit of insulation anywhere. Those are good ol' days that I have no intention of re-living.
Warm is good.
Jasper57
A couple of pics. I lied, too. I didn't do full outside radius cuts. Didn't feel the need. I know I put some fillers in (used waste from other cuts) in some locations for the blanks in the curve ... but not sure you really need them.
I did a floating wood floor over most of it. Tile in the bathrooms (on Hardi board).
That's great! Thanks for the pics. I imagine that the PEX has to move freely in the tracks and that you flow tested it before you put the floor on top?
Jasper57
I pressure tested before I put flooring down (using air pressure). The pex is able to move somewhat freely as it really isn't held in place or 'clamped' in any way. The warmboard allows NO movement as the tubing is held along the entire length including the curves ... where I allowed just a titch (that's a technical measurement term my grandfather used frequently) of 'flex' at each curve/switchback.
I didn't want to staple up from underneath as that seemed to me like the others found out ... a PITA. Even buying new A-C plywood and ripping your own strips was relatively easy. I laid it all out before laying down the tubing to check the layout and plan for adjustments. Once the bulk is in, you can make all your special/custom cuts and connections back to your vertical risers, manifolds, whatever.
I had a LOT of custom cuts, but you just lay it out and do each one.
I am also doing a DIY radiant system with the help of NRTRobs guys. I would highly reccomend talking with them. They will REALLY design out a system for you. No BS rules of thumb. You send them your floor plans and they will send you back a pretty great diagram of where to place the tubes and how the manifolds go together and most of the install issues are covered.
We went with tubes in the slab on the bottom floor and staple up for the middle floor. The bottom floor of our house is gutted so access to the underside of the joist bays was not an issue. I did not want to lose the height required by putting the tubing on top of the existing floor.
That said doing the staple up is a HUGE PITA!!! The under side of the floor has to be flat-smooth!! No nails, to cross brace obstrucitons not weird plumbing or gas lines in the way...take a look at the underside of your old floor....
I spent fricken days grinding off nails and cutting out cross braces and I'm still only half done!!!
We chalked out the outline of the walls-features on the underside of the floor so we knew where to place the thin-fins correctly-this was even a slightly bigger of a PITA than I had expected.
Stapling up the thin-fins themselves is kinda a PITA too. I don't know what I'm doing wrong but the 16 guage narrow crown staples I'm using in a Porter Cable gun almost NEVER go in well. The staples come out all mangled and distorted...Good thing is that they still hold the plates against the underside of the floor but I end up using an F-ton more of them to hold the dang plate in place. That and its not fun to be working over head for hours at a time in dirty dusty joist bays.
Rob sold us on a Triangle Tube Prestige Solo mod-con boiler for the system...I'm hoping to have heat by the time it gets really cold this winter....
Doing it yourself will save a ton of money. The local 'experts' wanted $8,000 just to tie the tubing to the rebar for the slab pour!!! We got the supplies and the plan from Rob for under 2 grand and got it done in a single weekend. Paying someone to do the staple up would be insanely expensive unless your're talking about day laborers...
hope this helps.
Daniel Neumansky
Restoring our second Victorian home this time in Alamdea CA. Check out the blog http://www.chezneumansky.blogspot.com/
Oakland CA
Crazy Homeowner-Victorian Restorer
I tried to staple up the flashing and UGH!
What a nasty job.. So I used my roofing nailer to shoot nails in , wow what a breeze. You might have too thin a floor to do that so what you need to do is use a stake or strip of wood to ensure the nails don't poke thru the floor.
If your floor is 3/4 inch thick you should use a piece of wood about 3/4 inches thick as a nailing strip that way the nails will miss poking thru by 1/4 of an inch or you you could use a strip of 1/2 plywood and slightly angle the nails either way will work..
That said doing the staple up is a HUGE PITA!!! The under side of the floor has to be flat-smooth!! No nails, to cross brace obstrucitons not weird plumbing or gas lines in the way...take a look at the underside of your old floor....
I spent fricken days grinding off nails and cutting out cross braces and I'm still only half done!!!
We chalked out the outline of the walls-features on the underside of the floor so we knew where to place the thin-fins correctly-this was even a slightly bigger of a PITA than I had expected.
Stapling up the thin-fins themselves is kinda a PITA too. I don't know what I'm doing wrong but the 16 guage narrow crown staples I'm using in a Porter Cable gun almost NEVER go in well. The staples come out all mangled and distorted...Good thing is that they still hold the plates against the underside of the floor but I end up using an F-ton more of them to hold the dang plate in place. That and its not fun to be working over head for hours at a time in dirty dusty joist bays.
Ditto - we ran into almost exactly the same situation.
Staple up sounds pretty easy, but the actual work is more time consuming, fiddly, and physically demanding than one might expect.
Well, the plot thickens...
The HVAC guy came over. Nice guy, well dressed (way better than me, anyhow). He is a big fan of radiant floors, but he suggested that they usually just use electric heat mats in bathrooms, but he is fine with me doing part of the work.
He said, however, that what they most often do to heat (and cool) the upstairs of old houses like this is a heat pump in the attic. I was really just shooting for heat in the key upstairs rooms we would use (we always used window units to cool the upstairs). The pump and ductwork is big bucks compared to what I expected to pay for this DIY Hydronic system. He also suggested replacing the oil burner with a heat pump downstairs for lower fuel costs and maybe (later) add a groung loop to feed both pumps. Not sure I'll live long enough to see the payback on all this?
One thing he said surprised me. He said that, (apparently due to code?), one hot water heater can't serve both domestic HW and the hydronic loop. I figured there was a way that it could be isolated with a backflow valve or something. Has anyone else heard that?
He certainly struck me as an honest guy, but I'd be interested to hear what others think of the notion that, for resale, heating and cooling the whole upstairs is important.
Thanks,
Jasper57
Nobody in their right mind should ever drink out of a hot water faucet.. Hot water causes lead to leach out of solder joints at greater rate and the potential for stale or contaminated water is great with hot water, Depending on code that's true.
. I have isolated my domestic water heater from my radiant water heater but I serpitiously cross connected them to use both should a need occur. (temps below minus 20)
Heat pumps can work fine if the cost of electricity is low enough..
They are basically electric heaters though. (abit more efficent than pure resistant heating elements) So if electric rates in your area are high be wary.
Yes, I sort of liked the idea of having an oil burner and a propane-fired heat system as well for the sake of not having all my eggs in one fossil fuel basket. The first floor is already running an electric central air system for that matter.
The prospect of someday adding solar collectors to the roof to pre-heat water for the hydronic loop looks like a lot less $$$ than drilling a ground loop (which he estimated @ $17.5K before any tax credits). He says tax credits might cut that in half, but they might do the same for a solar collector system as well.
I'm not a big fan of heat pumps and the first floor's ductwork is not designed for a heat pump. Maybe I need a central air conditioner in the attic?
Thanks for sharing your thoughts on this, Frenchy. It is a puzzle (made out of money).
Jasper57
I don't like central Air..
here's why..
A/C units are getting more and more efficent. What you buy tomorow will be obsolete in a a few years likely.. (as energy costs soar) In addition you have the expense of ducting.. now if it's furnace ducting it's backwards and thus very inefficent..
Heat rises cold air settles.. Heat should come out the bottom and leave at the top A/C should come out the top and drop to the bottom.
So either you accept built in inefficency or you install a second set of duct work for the A/C unit, or you go a third way..
I use window air conditioners. But I don't put them in windows..
Too inefficent and blocks the view..
I put them in walls. Up high! It's really simple to cut a hole in your wall, (insulate while you're at it) frame it out for A/C. Stuff a smallish room A/C unit in and go outside and put up trim around the unit..
Save your siding etc. for the plug you install during the winter. Picture on the inside, siding on the outside make a nice tight plug nicely trimmed. Will not make the A/C unit look unattractive when not in place..
Now here's the great part for a few hundred dollars you can buy really efficent A/C units. (get them off season and they are much cheaper)
I cool my whole house with two such units..
90+ degree days air so humid you need an aqualung to breathe and my 5500 sq.ft. house is kept cool with two window units stuck thru the wall. Total cost was under $500.00
OK my house is super insulated, you might need more or bigger units, but you won't need as much A/C as a central unit . The one is over my bed and on 90+ degree days I have to crawl under the covers as that cool air drops down and chills off the house.
The other is in the kitchen behind the cabinet doors.. When we use that one we empty the cups etc. out and open the cabinet doors.. My wife stands at the stove cooking on really hot days and sometimes goes looking for a sweater!
If the A/C unit should fail or need recharging etc. it's really simple to pull and replace..
I actually bought a spare unit but so far it isn't called for.. But if one fails I can be back up running in 30 minutes or less.. (depends on how much junk is up in the attic.)
Oh and last year we didn't spend $10.00 extra on electricity for the A/C units the whole summer.
Jasper:
I'm more surprised by "He said that, (apparently due to code?), one hot water heater can't serve both domestic HW and the hydronic loop. "
That's what a heat exchanger is for. My installation uses a single water heater, Polaris, to supply both domestic and radiant hot water. The heat exchanger separates the water supply between the heater and the radiant tubing - a closed loop system.You might want to get the famous "second opnion"!
I'm pretty sure the HVAC guy meant was that you can not have one single water heater heating both the radiant and DHW with the same water. Here the citys engineer was very, very clear on that-heck that seems to of been the main thing she was looking for-no intermixing of heating water and drinking water.
Daniel Neumansky
Restoring our second Victorian home this time in Alamdea CA. Check out the blog http://www.chezneumansky.blogspot.com/
Oakland CA
Crazy Homeowner-Victorian Restorer
I assume that is what he meant, but he said I would need two water heaters. He said there were boilers that also heat water, but that those boilers aren't as efficient in the Summer when they only are heating DHW. By the same token, there are HWH's that also do space heating as HH pointed out
That Polaris water heater looks pretty good, HH. I appreciate your second opinion. Polaris claims that one heater could heat 2900 sf plus DHW. That would be more than enough to do the entire second floor and downstairs rooms if I kept expanding the hydronic system.
Point taken on the built-in window AC units, Frenchy. There's a small room (basically a walk-in closet) between the bedroom we will use and the bathroom and that would move the AC noise away from our room yet still cool the BR.
It seems like there are always two ways to do any kind of remodeling project, the over $17K solution and the DIY solution. Decisions, decisions...
This is a great forum,
Jasper57
That $17K would buy a lot of beer.
Joe H
Well, that settles it... ;-)
Jasper
Check out http://www.heatinghelp.com. I think it is mostly pro's so respect that but read everything there and search the archives. You can download the Radiant Panel Association publications very reasonably and I found them to be invaluable. Slant Fin's design software seemed comprehensive and was easy to use. http://www.pexsupply.com is another source I like.
I chose a Lochinvar Knight modcon boiler and only got to run it a few weeks last spring before it got warm out (and will fire it back up soon) but it was a great feeling of accomplishment feeling the warmth from the floors after all the research and time of building the system. I had countless hours soldering the primary and secondary loop setup together but if your budget allows you can get a custom one pre assembled for mounting to your wall. My research showed that like most subjects some radiant theories of design were loved by some and hated by others (like zone pumps vs. zone valves). Research it all, decide what your gut thinks is best and move forward and don't look back. With common sense and due diligence any serious DIYer can build an acceptable system. Final thought, I purchased the boiler from a local HVAC dealer that would work with me instead of online. You 'may' have support or warranty issues buying some equipment online.
GregT
I've set up a meeting next week with the HVAC guy recommended by Warmboard. He kind of knocked the idea of an energy audit. He says a blower test may not work if the house is too leaky. I dunno if the house is that bad off, but I appreciate him coming out to take a look. I'll let you all know how that comes out.
Thanks for all the input, gents. I'm still not sure if this house project is within my skills, but I think there's enough good advice here to keep me from going too far off the rails.
Stay tuned,
Jasper57
Edited 10/25/2008 12:51 pm ET by Jasper57
re: my home made warm board .... Like anything ... pay your money, take your choice. If you have time and less money ... do it yourself warm board will cost you about $1 a sqft for the plywood ($32 or less a sheet and no shipping charge) vs. $6, but then you have youre effort to cut it and the additional effort to install. IMO it ain't a bad choice.
Yeah, it's hard to argue with doing home-built for the first couple of rooms at least, but I want to see what the HVAC guy sez. He may have some other idea altogether and, I'll be interested to hear what he says about hot water heaters vs. boilers. I suspect I'll end up doing a mixture of subfloor tubing and, err.. sub-subfloor tubing.
Thanks again,
Jasper57
Yeah ... just more food for thought. You weren't full yet, were you? :)
Well, I quit thinking for a while today and went to work on the house instead. I try not to think when I work. It goes faster that way. :)
Jasper57