Second thoughts on radiant floor heat

[Tom Kochtanek]

OK, the walls are up and now I am having second thoughts on installing radiant floor heat under the 40' by 60' concrete subfloor. Here's why:

About half will be used as "dead storage" for future projects and parts and such. I promised 100 square feet of storage to my lovely wife for her furniture projects. Another 100-150 will be framed up with inside walls and made in to an office. There will also be a bathroom and possibly a shower (sounds like I'm moving in!).I can see heating/cooling to office area and bathroom using local sources (space heaters, window A/C, etc.)

So why bother heating some 1200 square feet of storage space (the dead space next to the active space)? It (the dead space) might be open to the rest of the building where the action is taking place, but no need to heat it. Plus it will be an "ocassional place", not a place of work where money needs to be made. If it's too cold or too hot I won't need to be there.

I'm looking for some advise here. It will run about $5000 for the materials, with me doing the installation. I am also worried about long term utilities, this one will be (must be) based on natural gas, not propane, not wood. Can't use a wood burning stove, insurance won't cover the building. Original thoughts were to hang a big gas furnace like you see in many shops. Blows down on you. My ceilings are 10 footers. I can "separate" that half that needs no utilities with a drop plasic or some such movable barrier, to help keep the heated area from the unheated area, if need be. I also thought about using radiant heat under just half of the floor, where the shop space will be.

Still trying to figure out if this is the way to go. The $5K up front isn't the big issue (well, sorta), but heating all that dead space might be (long term costs associated with natural gas). Plus it won't be an "everyday thing" until retirement, maybe not even then. Just a hobby place... Any advise would be most helpful.

Thanks!
TomK

[dads 409]

tom did you think about a corn furnace? we put one in our house about mid feb. and it cost us about 4200.00 but only 25-28 bucks a week to heat our old 2 story house and she kept the thermostat at 72-74 deg.

[Firepower354]

Sounds like quite a place! I build quite a few garage/workshops in chilly MI and have tried most methods of heating them up. My humble thoughts presented:

Radiant heat is nice, and branching into zones takes care of the "wasted" heating. You should be able to buy the stuff for alot less than 5K though, especially if you use a conventional water heater (or two)rather than a boiler system. High initial cost, rather slow temp rise, and lack of air movement are downsides.

The hanging jobs are typically noisy, too far from the floor, area specific, and sorta ugly.

Just a thought, $1000+/- buys a downflow house-type furnace and a bunch of ductwork. $500 would cover an office only unit. Insulated ducts and plenty of floor level vents along with insulation under the outside couple feet of slab makes for a nice workspace. The blower running even without the heat on cuts down the "garagey" smells, and central air conditioning figures in pretty cheaply. A few $13 ceiling fans from Target including light kit will help. You can shut off the ducts to the areas not in use. The plastic drop-wall wouldn't be as effective as a few 2x4 framed panels with insulation and OSB, built in managable sections, fairly easily moved to match your shop vs. storage needs. Turn the dial heat is tough to beat. Remote or programmable thermostats save money long-term.

Don't forget the phone(bell and flashing light), speaker, and cable jacks, intercom, etc before you finish the walls.

[No409]

My dad put a oil furnace upstairs in our garage, and ducted it downstairs. heats up really quick, pretty efficant. our garage is 36x42

[wrench]

OK, the walls are up and now I am having second thoughts on installing radiant floor heat under the 40' by 60' concrete subfloor.
I'd go with just using it on the areas most used, the office and the work area. You don't want to lay on a cold concrete floor - trust me. You won't need it in the storage areas. As for cordoning off the area not heated....you might consider a single insulated wall. That would guarantee no real heat loss. Sheet plastic could work also, but managing it can be a hassle. I googled: http://www.acousticalproductscompany.com/Partitions.ivnu This may be a viable option. Or you can build a PVC and tarp movable partition see my drawing below). That way you tailor it to your own dimensions and desires, even put in a door thru it for easy access to the storage side. You'll need to split the floor areas in the forms setup, I'm sure you know about that already. You can use standard ceiling fans to move the warm air around. We had them in our old shop and they were 18 feet high, and they worked great.

I've been looking for your place with Google Earth......where is it?

:cool:

[Tom Kochtanek]

Wrench:

I wasn't aware of Google Earth until you mentioned it. Seems like it is in "beta" testing, and they're not taking on new clients right now, but it sounds like it is free. Here's the address:

3510 Scott Boulevard
Columbia, Missouri 65203

It's on the East side of Scott Blvd nestled between two larger subdivisions. It will appear as the only undeveloped tract right around there, but there is a strip of land that used to be a RR track that runs nearby. It's a jogging/nature trail now -- I think of it as one of the ameneties :).

Let me know if you can spot it!

Best,
TomK

P.S. Google Earth uses GPS and satellite images to form up-to-date searchable maps of the planet Earth. Pretty cool stuff!

[oldskydog]

No problem! Two solutions to your problem:
1. Hook up a 409 to aheat exchanger
2. Move the manshop to Arizona :rofl

[jester]

PUT THE FLOOR HEAT IN NOW !

Trust me with this one. I know very little about 409's, Radiant floor heat I do.
I designed and installed a 4 zone system for my home 5 years ago. The best thing I ever did.
Put in the system now but . install several loops , keep the loops under 200' if possible. Connect them to a manifold. If you put shut off valves on each end of the loop , you can control the heat in the area you want . After you pour the floor , IT WILL BE TO LATE.
Remember, things change. Your need for the space might be different tomorrow.
(once that floor gets warm, it stays warm( It's the best heating system , cost is more to install but well worth it in the end.)

[fatride]

What Jester said.

[Tom Kochtanek]

Jester/Fatride:

Can you tell me who you purchased your components from?

TomK

[fatride]

I haven't purchased the tubing yet. I have a boiler. I am researching under slab insulation.

[jester]

try Insulation4less.com or pioneer building product. There are a bunch of suppliers on the net.
As for thr plumbing supplies, any good plumbing supplier shoulld be able to give you everything that you need.
As for the boiler, You need to remember that you will only be heating the water to about 130 degrees Any more and you shorten the life of the tubing. I heated my whole house for 2 years with a hot water heater. If you can sweat a solder joint you can do this.
Do it once and do it right the first time.
E-mail if I can help.

[Fran Preve]

This is MOST important!. No matter WHAT you do, put HEAVY plastic down over your base BEFORE you pour the concrete!. If you don't I guarentee your floor will "sweat"!. My garage is 24 x 37 and the guys who dug the foundation and poured the floor did a FANTASIC job!. But they didn't put down a vapor barrier (cost about $30). I never realized it or thought about it. Now my floor sweats.

The only other comment I have is, don't worry about a cold garage floor, a large piece of cardboard and a piece of carpet will get you thru the few hard times, in my opinion.

[wrench]

Let me know if you can spot it!

Here it is?

[jester]

Did I forget to mention that I heated my 1500 sq ft. home in the Adirondack mountians for$450.00 last year. It's not a question of sitting or working on a cold floor , it's the floor becomes a 1,000 square foot. radiator

[wrench]

Did I forget to mention that I heated my 1500 sq ft. home in the Adirondack mountians for$450.00 last year. It's not a question of sitting or working on a cold floor , it's the floor becomes a 1,000 square foot. radiator

Great comment on the different zones thing. I didn't think of that at all.

Most of my radiant heat comes from the 'top' :rofl here in TX! :D

:cool:

[jester]

Great comment on the different zones thing. I didn't think of that at all.

Most of my radiant heat comes from the 'top' :rofl here in TX! :D

:cool:
I see what you mean. I guess you guys in Tx spend your time tring to cool things down.

[Tom Kochtanek]

OK, second thoughts aside, I am now re-looking into my options. One thing I hadn't thought of was using the sun to heat the water for the radiant floor system. I have contacted two vendors and they are preparing bids for the Manshed, including the technical details behind solar-powered systems. Time to get educated. Been reading lots these past two days on DIY systems, and hope to make a good decision in the weeks ahead. I guess since I've been waiting for this to happen for so long, it won't matter if it takes me a few more months to do the right thing :).

Here's where I'm looking now:

http://www.radiantec.com/whyradiant.htm

and here's a government report I came upon:
http://www.eere.energy.gov/consumerinfo/factsheets/ad8.html

and an article from an independent source that I found quite informative:
http://www.eere.energy.gov/consumerinfo/factsheets/ad8.html


More later as I educate myself in these systems.

Tomk

[wrench]

More later as I educate myself in these systems.

Did I get the location right?

Tom C

[Tom Kochtanek]

Wrench:

You were real close. I am in the 3500 block of Scott Blvd., about a quarter mile South of the location you came up with. I loaded the Google Earth client two days ago, pretty cool stuff. The satellite photos are about 3 years old, so far as I can tell. I can tell because I took a lot of trees down last summer, and they still show up in "Earth".

I tried to load the client software application on my laptop today, but it seems as if they are not allowing new users for the moment. Hopefully they will have up-to-date satellite photos up in the near future. Just think if they had "real time" satellite images -- you could watch machines rove around and lay concrete on that property!

Best,
TomK

P.S. Road bed is in! A few glitches, but it's progress...

[RCE1962]

Jester

Currently, the in-floor radiant heating scenario is considered to be one of the most efficient. It does not have the wide temperature swings related to "forced hot air" heating systems. I'd have to agree with the previous posts advocating "in-floor" heating.

Zoned areas within the building are up to you, but if you have any intention of selling the property, the next owner may recognize some contributory value to your fore-thoughts on maximizing this feature.

RCE1962

[ROYALOAK62]

Tom,
Solar heating is great cost wise (after it's installed). But one question. How many sunny days do you have in your heating season? In Michigan people only use solar as a second source. It gets cold fast on non-sunny days.

Dave

[Tom Kochtanek]

Dave, that IS something to consider. Here in Missouri weather changes a lot, sometimes overnight. It's certainly not Arizona, but it's not Portland or Syracuse, either. Most everyone agrees that solar is nice, but you need a backup. That means two systems, two expenditures.

My approach is, if it's cold out and cloudy, I just won't go out and play :). This is not my house, not my job. It's 4 miles away, and my hobby. I guess that's taking it a bit casual, but that's how I am thinking.

One problem with solar that a lot of people don't think about is what to do with the "solar gain" (all that hot water) generated in the SUMMER? You still have these panels converting energy into to heat, and you have to "dump" it somewhere. Some bleed the system off and water their gardens, but we're talking about 30 gallons of (warm) water a day... Swimming pool? Sauna? Now we're really getting expensive!

I'm still "at the drawing board" looking into options and checking things out. One direction would be to just go ahead and put that VEX tubing over insulation (and a vapor barrier, as Fran suggests) and pour the concrete, that way I'll have the option to use radiant heat if I so choose. The tubing isn't cheap, but the heating unit and the manifolds make up most of the cost. At around 70 cents a foot, that tubing is somewhat costly (I'm getting estimates right now), but it does provide for options.

More later as I make my decisions. It'll have to happen quickly, because I want to move on this project by Fall.

Best,
TomK

[wrench]

I'm still "at the drawing board" looking into options and checking things out. One direction would be to just go ahead and put that VEX tubing over insulation (and a vapor barrier, as Fran suggests) and pour the concrete, that way I'll have the option to use radiant heat if I so choose. The tubing isn't cheap, but the heating unit and the manifolds make up most of the cost. At around 70 cents a foot, that tubing is somewhat costly (I'm getting estimates right now), but it does provide for options.

Hey Tom, have you considered using an underground loop to cool it in summer also? It's gonna be warm under that roof (if the Global Warming people get thier wish).

:cool:

[Tom Kochtanek]

Wrench, I was hoping that since it is a subterranian underground area with some earth contact, that it would stay cool like my basement does at my house. No plans for A/C at the moment. We shall see!

TomK

[Dond409]

Hey what about Syracuse. :cuss

[Tom Kochtanek]

Sorry Don, didn't mean to knck you're hometown :).

In 1984 or thereabouts I had an offer to join the faculty at Syracuse University, really great money, but my wife of now 26 years took a look at the 243 or so odd days of the year that the sun did not shine there and nixed the deal :(.

I guess that's always stuck with me....

Any solar collectors in your area?

Best,
TomK

[Dond409]

No Tom, not very many that I have seen. They are in the process of building a wind power complex up in the Tug Hill region