OP
Dave Maxwell
Well-known member
If the radiant turns out to be higher priced. I will be one pissed off person. Switch to forced air if it dors
heating cost. floor vs. air
- Thread starter Dave Maxwell
- Start date
Shop Specialties
Well-known member
It is only messy if YOU make a mess. I have many customers heating there shops and homes with a waste oil boiler. I tell people if they can generate 500+ gallons a year then it is worth it. Then you factor in the tax credits for using waste oil especially here in Montana it makes it cheap. Did you know you can buy spec oil for $ 1.50/gallon or cheaper delivered ? That right there makes it the cheapest, highest BTU fuel in Montana. My parents use a waste oil boiler to heat the shop and house. My Mother has not complained once and trust me if it is dirty and skunk smelling it would have been removed a long time ago.
I would go forced air any day before overhead radiant tube, but that is just my opinion of being around them for 21 years in various applications.
Shop Specialties
Well-known member
Floor heat is really that cheap to run 24/7. That is one of the big selling points of it. It obviously needs to be designed and installed correctly like anything else to work properly.
OP
Dave Maxwell
Well-known member
I look at the hydronic heat like I do my deep freeze. Once the items are warm it should somewhat self sustain. I keep my deep freeze full of frozen jugs of ice
Shop Specialties
Well-known member
In floor heats objects, forced air heats the air. Which one do you think is going to retain heat longer - the slab or air ?
I had a customer on a Friday night drinking beer shut off the air compressor to drain it. Well they forgot to turn it back on so the waste oil boiler shut down. They did not notice until Monday afternoon that it was getting chilly in the shop.
I had a customer on a Friday night drinking beer shut off the air compressor to drain it. Well they forgot to turn it back on so the waste oil boiler shut down. They did not notice until Monday afternoon that it was getting chilly in the shop.
Shop Specialties
Well-known member
Here are some actual real numbers from a customer of mine. CAA in Miles City, MT is a 12,000 sq. foot shop/offices/showroom/etc. I last cleaned the waste oil boiler on Feb. 7 of this year and on May 10 it had only ran 300 hours. They keep it at 70* at all times and they have snowmelt.
93 days x 24 hours = 2,232 hours.
So in 2,232 hours the boiler only had to run for 300 hours to maintain 70* in a 12,000 sq. foot area and do some snowmelt.
This just goes to show how efficient a properly designed and installed radiant floor heat system is.
93 days x 24 hours = 2,232 hours.
So in 2,232 hours the boiler only had to run for 300 hours to maintain 70* in a 12,000 sq. foot area and do some snowmelt.
This just goes to show how efficient a properly designed and installed radiant floor heat system is.
KPSquared
Well-known member
How many hours does a forced air or radiant tube unit run? Kinda need those numbers for your example to mean anything. . .
In that situation, it makes sense from a cost perspective, but I'm still not sure I can justify it in my garage.
I would love to figure those numbers out somehow. Say it costs me $8000 - $10000 more for a heated slab vs. my radiant tube. . .how many years is it going to take to break even?
if I'm only at this place for 10 years, I doubt I'd get a solid return on my investment so then I'd have to decide if it was just a luxury I wanted to afford. .at this point, I can't.
In that situation, it makes sense from a cost perspective, but I'm still not sure I can justify it in my garage.
I would love to figure those numbers out somehow. Say it costs me $8000 - $10000 more for a heated slab vs. my radiant tube. . .how many years is it going to take to break even?
if I'm only at this place for 10 years, I doubt I'd get a solid return on my investment so then I'd have to decide if it was just a luxury I wanted to afford. .at this point, I can't.
Shop Specialties
Well-known member
Well first we would figure we would need 2/3 MORE BTU to go forced air or radiant tube. Just look at what your current costs of Natural Gas or Propane is in your area. Then look at all the benefits between the 3. Even heating, dry floors, snowmelt in front of garage door ?, you will have a higher resale value with infloor.
The infloor is cheaper to use and will add value to your building.
If you cannot afford to install it in the first place you should not even be thinking about it.
The infloor is cheaper to use and will add value to your building.
If you cannot afford to install it in the first place you should not even be thinking about it.
Highbeam
Well-known member
Come on now, 8-10k$?
You will find that unless you hire out the job to some fancy schmancy company that these things can be put together for much less money.
1000$ for pipes and plumbing. Another thousand for a heat source and pump.
Look at some of the threads on this site for examples of cheap systems using new components. You can go mild to wild.
You will find that unless you hire out the job to some fancy schmancy company that these things can be put together for much less money.
1000$ for pipes and plumbing. Another thousand for a heat source and pump.
Look at some of the threads on this site for examples of cheap systems using new components. You can go mild to wild.
KPSquared
Well-known member
I got quotes MUCH higher than that for heat source and pumps and such.
I'll do some reading for sure. The local numbers I got on infloor just made it seem like an impossibility for me.
It's not that I can't afford it, it's that I'm not sure if I want to. I will do some more reading. Even just to insulate the slab is going to cost well over $2000. . . and after chatting up a bunch of local guys, no one around here does it. I just get sideways looks when I mention that or poly or anything.
I'll do some reading for sure. The local numbers I got on infloor just made it seem like an impossibility for me.
It's not that I can't afford it, it's that I'm not sure if I want to. I will do some more reading. Even just to insulate the slab is going to cost well over $2000. . . and after chatting up a bunch of local guys, no one around here does it. I just get sideways looks when I mention that or poly or anything.
wedge40
Well-known member
I've never heard of someone putting the XPS right on the gound.. I've alway thought you should put 6mil plastic down between the ground and XPS.
I have 2240 sq/ft that I'm going to put the tube in and not sure when I'll finish the system.. Adding the tube after the fact is not a good option. Like someone said in an earlier reply.. Even if I never hook it up, it's still a good selling poing. I've waited years to get the garage/barn built and I'm wanting to do it right. Once I get the cement poured I plan I saving the money to have 1"-2" of foam spraying on the interior walls. This should seal the place up well and I will finish with fiberglass after.
Wedge
I have 2240 sq/ft that I'm going to put the tube in and not sure when I'll finish the system.. Adding the tube after the fact is not a good option. Like someone said in an earlier reply.. Even if I never hook it up, it's still a good selling poing. I've waited years to get the garage/barn built and I'm wanting to do it right. Once I get the cement poured I plan I saving the money to have 1"-2" of foam spraying on the interior walls. This should seal the place up well and I will finish with fiberglass after.
Wedge
bbailey
Well-known member
I have radiant in floor heating. 24 X 40 with 16' ceilings and neighbors on 3 sides. I live in MN and we had a mild winter. I kept the garage in the low 50 degrees. My electric bill has been $15 - $25 per month for the last 10 months. Next winter I will keep the place warmer and pay an additional $5.
I also get a small amount of sunlight on the outside wall/door and have a couple of windows.
I have a programmable thermostat and off peak rates that are 20% of the on peak rates. I heat the place off peak and the radiant factor keeps it consistent.
I cannot quickly warm the place though. I sometimes use small "Amish Style" space heater (and ceiling fan) which ***** juice, but makes a difference.
I also get a small amount of sunlight on the outside wall/door and have a couple of windows.
I have a programmable thermostat and off peak rates that are 20% of the on peak rates. I heat the place off peak and the radiant factor keeps it consistent.
I cannot quickly warm the place though. I sometimes use small "Amish Style" space heater (and ceiling fan) which ***** juice, but makes a difference.
Chaz
Well-known member
A BTU is a BTU. The radiant floor heat is expensive to install. takes a long time to react to temperature changes and does not filter the air.
A warm floor is nice, but in-floor radiant is way overrated in my opinion. I know of 3 folks that have it and wish they'd have gone forced air.
A warm floor is nice, but in-floor radiant is way overrated in my opinion. I know of 3 folks that have it and wish they'd have gone forced air.
dirttracker18
Well-known member
FWIW
I don't know anyone that has regretted the decision to go in-floor except a few that thought they could do it themselves and messed it up (no insulation under, bad layout, not enough pex, etc.)
Almost everyone that has worked in my shop has regretted not doing it in their's. Eventually they always say "it is so comfortable in your shop." To which I reply, in-floor heat. Their response, "I wish I went that route."
Highbeam
Well-known member
30x46' is what you're building so 1400SF, use 1500 LF of 1/2" pex. Should cost you 500$ from pexsupply or another online store.
1400SF/32 is 44 sheets of foam. I paid just under 20$ per sheet of 2" thick 25 psi foam from the factory which would cost you another 900$. You should insulate your slab nomatter the heat source so this cost is not extra for in floor heat.
Some zip ties, some 6 mil VB, you're done for 1500$. Let them pour the slab. Later on you can hook up the tubes to a water heater or boiler plus assorted devices and fittings for another 1000$.
I know the canadian dollar used to be worth less than the US dollar but isn't that flopped now?
Attachments
Shop Specialties
Well-known member
Who has a furnace in a shop that filters the air ?
Radiant floor heat has gotten a bad rap in Montana mainly due to the fact of poor installs. I know of a couple of outfits in Missoula that claim they know what they are doing and screw up more things than make right. You need to check out Montana Radiant in Missoula. Glen is one of the best in the nation and has fixed many screws up across the state.
wedge40
Well-known member
I've experienced just about every type of heating system possible for the home – forced air, air source heat pump, ground source heat pump, boiler feeding radiators, etc. My current home is hot water in-floor radiant – it offers so many benefits it is hard not to enjoy or recommend:
- as mentioned earlier it just feels good – once setup properly you hardly ever feel cold or warm – just right. (hard to explain)
- warm floors = comfortable feet in the mornings.
- Floors joists do not squeak because the structure to contain the heating loops is extreme..... in my case (2x12” floor joists + 3/4” plywood + 1.5”-2.0” concrete + flooring material
- boots/shoes are warm when you put them on
- just throw wet gloves, etc. on the floor and they'll be dry in an hour or so. Contrary to telling the kids to hang their stuff up but really effective when you've been in the snow or rain
- quiet operation
- dust is not “blown” around (perhaps better air quality?) ….there is always dust - just not being blown around
- zone controls allow variable temperature throughout the house - perhaps by area (zone) or by time of day.
Our system consists of several zones – each with its own thermostat and also outside thermostats so that a temperature balance can be maintained - even when the sun is radiating on a wall of windows . Also since I am talking about a home another positive is that your central A/C vents can be placed in the ideal location for cooling (near ceiling).
Negatives (for homes):
- $$ you are paying for almost two complete heating systems (since most would also want A/C in their home (forced air) and the A/C needs duct work the only thing missing is a heating element.)
- flooring limited to products that hold up well to radiant heat and allow decent heat transfer (engineered hardwood, ceramic) ...you can also use carpet but heat is somewhat trapped by the material
- what happens if leak occurs in the tubing (for whatever reason) …..has not happened to me but I can imagine a real nasty fix. Sooo.. you have to be conscious regarding nailing or drilling into floors (from top or bottom) perhaps to snake new cabling, etc. You really need a blueprint that shows exactly where the tubing was laid
Garages / shops: For a new shop I'd go radiant but make sure you blueprint the location of the lines.
Installations: While our radiant system is near flawless in performance, I give much of the credit to the installer. While I don't know exactly what goes into sizing a system, determining how many zones,best layout of the loops, loops length etc. , one theme I can say for certain is that the 2-3 systems I know of locally (all very happy homeowners like myself) have a near perfect looking “zone control center”.... the copper pipes are parallel, the soldering is clean – almost polished (no solder drips), the valves are all in line, the entire system is organized. That said... I have seen other systems (installed by other companies) that are a mess to look at and as you might expect – the owners are not so happy with performance. Sooo... my advice is simple – don't just talk to other past clients – at the least get pictures of the finished installations and if possible go see for yourself.
Sorry for the long response... thought it might be helpful
- as mentioned earlier it just feels good – once setup properly you hardly ever feel cold or warm – just right. (hard to explain)
- warm floors = comfortable feet in the mornings.
- Floors joists do not squeak because the structure to contain the heating loops is extreme..... in my case (2x12” floor joists + 3/4” plywood + 1.5”-2.0” concrete + flooring material
- boots/shoes are warm when you put them on
- just throw wet gloves, etc. on the floor and they'll be dry in an hour or so. Contrary to telling the kids to hang their stuff up but really effective when you've been in the snow or rain
- quiet operation
- dust is not “blown” around (perhaps better air quality?) ….there is always dust - just not being blown around
- zone controls allow variable temperature throughout the house - perhaps by area (zone) or by time of day.
Our system consists of several zones – each with its own thermostat and also outside thermostats so that a temperature balance can be maintained - even when the sun is radiating on a wall of windows . Also since I am talking about a home another positive is that your central A/C vents can be placed in the ideal location for cooling (near ceiling).
Negatives (for homes):
- $$ you are paying for almost two complete heating systems (since most would also want A/C in their home (forced air) and the A/C needs duct work the only thing missing is a heating element.)
- flooring limited to products that hold up well to radiant heat and allow decent heat transfer (engineered hardwood, ceramic) ...you can also use carpet but heat is somewhat trapped by the material
- what happens if leak occurs in the tubing (for whatever reason) …..has not happened to me but I can imagine a real nasty fix. Sooo.. you have to be conscious regarding nailing or drilling into floors (from top or bottom) perhaps to snake new cabling, etc. You really need a blueprint that shows exactly where the tubing was laid
Garages / shops: For a new shop I'd go radiant but make sure you blueprint the location of the lines.
Installations: While our radiant system is near flawless in performance, I give much of the credit to the installer. While I don't know exactly what goes into sizing a system, determining how many zones,best layout of the loops, loops length etc. , one theme I can say for certain is that the 2-3 systems I know of locally (all very happy homeowners like myself) have a near perfect looking “zone control center”.... the copper pipes are parallel, the soldering is clean – almost polished (no solder drips), the valves are all in line, the entire system is organized. That said... I have seen other systems (installed by other companies) that are a mess to look at and as you might expect – the owners are not so happy with performance. Sooo... my advice is simple – don't just talk to other past clients – at the least get pictures of the finished installations and if possible go see for yourself.
Sorry for the long response... thought it might be helpful
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KPSquared
Well-known member
Great theory but there are some issues. . .oh, and it's only 30x36. . .
The canadian dollar might be on par or higher but "free trade" only benefits the US. . .by the time we pay duties, shipping, and taxes, our pricing its completely out to lunch. I priced 2" foam. . .$28/2x8 sheet. That's only 16 sq. feet. I need 60 sheets. . .that's $1765 with tax.
I had never budgeted for this option. I'm wishing I had. I don't understand why no one insulates slabs here considering the huge temperature swings. . .+35°Cto -40° C is a big span. . . I'm going to do a little more research.
Shop Specialties
Well-known member
You are under 500 miles from Kalispell so come on down. The exchange rate might pay for your fuel. I cannot think of the name of the business right now in Kalispell but they will design everything for free if you buy from them. They even solder the pump panel together for you so all you have to do is mount it on the wall and plug everything into it. After looking at the work you have already done you could easily handle doing it yourself. If you poured concrete between your house and a apron in front of the garage with tubing imagine how much less snow you would have to shovel and no ice to slip on.
hidollartoys
Well-known member
Another FWIW: I am just starting the construction of a 40x80x12 all steel building and decided to go with in floor radient. I have done "some" research and talked to "some" that have experience with the systems. I live in Kansas City metro which is not the great white north, so I expect design and installation are not as super critical as they would be in MT, MN or Canada.
I am putting 1" 25psi foam under the slab and 2" foam around the parameter. Floor is 6" thick on 12" wide x 36" deep frost footing. 3/4" pex on 18" centers in middle of slab with 2 loops on 12" centers along the parameter. I have 8 loops, all just under 300' in length. I will have 4 "zones", each heating 800sqft. I will have a 40,000 btu water heater at each zone. That is 50btu/sqft.
So far, $1200 for pex, $1900 for foam and extra $3600 for footer instead of piers. I hope my extra cost is well spent. I do expect to have some sort of aux air to air heat source. I believe this the "cost of admission". We spend a lot of money just to build these buildings and I think the investment to be able to use them year round is just good sense.
I am putting 1" 25psi foam under the slab and 2" foam around the parameter. Floor is 6" thick on 12" wide x 36" deep frost footing. 3/4" pex on 18" centers in middle of slab with 2 loops on 12" centers along the parameter. I have 8 loops, all just under 300' in length. I will have 4 "zones", each heating 800sqft. I will have a 40,000 btu water heater at each zone. That is 50btu/sqft.
So far, $1200 for pex, $1900 for foam and extra $3600 for footer instead of piers. I hope my extra cost is well spent. I do expect to have some sort of aux air to air heat source. I believe this the "cost of admission". We spend a lot of money just to build these buildings and I think the investment to be able to use them year round is just good sense.
Shop Specialties
Well-known member
How well are you going to insulate the building ? You should be able to do much better than 50 BTU per sq. ft.
OP
Dave Maxwell
Well-known member
Under slab. Will I notice much difference between the one inch r5. The 1.5 inch r7.5 or the two inch r10
hidollartoys
Well-known member
The building will get r-13 blanket , roof and walls sandwiched between steel siding and purlins. The building is built with purlins on 24" ctrs running horizontally so I will also install r-13 batts between these purlins and finish the walls and ceiling/roof with either steel or wood product. There will also be additional air infiltration prevention measures incorporated. No windows, (3) insulated o.h. doors and (1) 3'0" insulated man door.
Red Goat
Well-known member
I just got my permits for a new garage in Denver and the building dept is requiring:
R15 against the foundation walls to the footings
R10 below the slab
R21 in the walls
R38 in the ceiling
This garage will be far better insulated than my house!!!
R15 against the foundation walls to the footings
R10 below the slab
R21 in the walls
R38 in the ceiling
This garage will be far better insulated than my house!!!
dirttracker18
Well-known member
Foam board is half the price in the US as it is in Canada.
This makes it well worth the trip to go pick it up. However, Menards delivers into Canada (at least around here) and the delivery can be reasonable, especially if you order more of your garage there.
Here, many guys order the entire garage package out of Menards and have it delivered here. The sad part is that often the wood you get was harvested and sawn here (by here I mean literally in and around my city) but is cheaper to buy out of the US
Dick in Wisconsin
Well-known member
How close to Thunder Bay is there a Menards store? Grand Marais, MN?
dirttracker18
Well-known member
Duluth, MN is the nearest Menards.
BadgerBoilerMN
Well-known member
We design all sorts of garage heating systems. If naturally follows that the least expensive product also does has the worst performance.
We first consider human comfort. This eliminates over-sized gas-fired unit heaters. We are then left with infra-red tube heaters and radiant floor, wall or ceiling panels. We install many infrared tube heaters in residential two-stage sizes. We call this the "never too late" system as it will give you reasonable comfort and efficiency if properly applied according to heat load, ceiling height, etc.
Infrared can give you the "hot head" syndrome, makes more noise and should be have ducted intake and exhaust. Large vehicles and other flat surface can block the radiant effect. Still fast and relatively cheap to install. The tube reflector and tube itself must be maintained or efficiency and comfort will diminish over time.
Radiant floor stands alone for comfort. The slab is a natural and already paid for radiator, which protects the PEX from nearly any threat. Radiant floors and ceilings can be driven by any heat source, be it wood, NG, propane, or even electricity. You may also change your mind and your boiler if one fuel becomes too expensive.
Radiant floors are also exclusive in their control features. The water temperature, and consequently the comfort and fuel economy can be (should be) controlled. Outdoor reset is an essential part of our radiant floor designs.
A properly designed radiant floor heating system lowers the heat load of any building by lowering the difference in temperature between outdoor and indoor surfaces. Typical surface and design water temperatures are well below human body temperatures. All warm air heating system stratify super-heated air at the ceiling and drive energy out and fuel bills up.
By contrast the surface temperature of an infrared will always be in the hundreds of degrees Fahrenheit (typically 350-100°F). Though the majority of energy will be transferred to walls and floors a significant percentage ends up at the ceiling.
Only radiant floors and to a lesser degree, radiant ceiling will usually have matching ceiling and floor temperatures with ambient air temperature (thermostat setting) a couple of degrees below.
It reminds me that some pretty good mechanics can get by with the most God forsaken tools and still do adequate work. I am a licensed plumbing and mechanical contractor and have but one Snap-On ratchet, but if I lost it, I would by another tomorrow. That is the difference between radiant floor heating and just good enough. Tools are a weakness, but you could have worse habits.
We first consider human comfort. This eliminates over-sized gas-fired unit heaters. We are then left with infra-red tube heaters and radiant floor, wall or ceiling panels. We install many infrared tube heaters in residential two-stage sizes. We call this the "never too late" system as it will give you reasonable comfort and efficiency if properly applied according to heat load, ceiling height, etc.
Infrared can give you the "hot head" syndrome, makes more noise and should be have ducted intake and exhaust. Large vehicles and other flat surface can block the radiant effect. Still fast and relatively cheap to install. The tube reflector and tube itself must be maintained or efficiency and comfort will diminish over time.
Radiant floor stands alone for comfort. The slab is a natural and already paid for radiator, which protects the PEX from nearly any threat. Radiant floors and ceilings can be driven by any heat source, be it wood, NG, propane, or even electricity. You may also change your mind and your boiler if one fuel becomes too expensive.
Radiant floors are also exclusive in their control features. The water temperature, and consequently the comfort and fuel economy can be (should be) controlled. Outdoor reset is an essential part of our radiant floor designs.
A properly designed radiant floor heating system lowers the heat load of any building by lowering the difference in temperature between outdoor and indoor surfaces. Typical surface and design water temperatures are well below human body temperatures. All warm air heating system stratify super-heated air at the ceiling and drive energy out and fuel bills up.
By contrast the surface temperature of an infrared will always be in the hundreds of degrees Fahrenheit (typically 350-100°F). Though the majority of energy will be transferred to walls and floors a significant percentage ends up at the ceiling.
Only radiant floors and to a lesser degree, radiant ceiling will usually have matching ceiling and floor temperatures with ambient air temperature (thermostat setting) a couple of degrees below.
It reminds me that some pretty good mechanics can get by with the most God forsaken tools and still do adequate work. I am a licensed plumbing and mechanical contractor and have but one Snap-On ratchet, but if I lost it, I would by another tomorrow. That is the difference between radiant floor heating and just good enough. Tools are a weakness, but you could have worse habits.
BadgerBoilerMN
Well-known member
Insulation R-value is dictated by indoor vs. outdoor design temperature. For the money and labor involved R-10 (2 inch XPS) board insulation is a good by and will stand up to foot traffic while installing PEX tubing and concrete men.
In colder climates we will bump up perimeter insulation to match design conditions.
In colder climates we will bump up perimeter insulation to match design conditions.
OP
Dave Maxwell
Well-known member
Is the two inch good for the sides as well.
Highbeam
Well-known member
Good post badger, that long one.
OP
Dave Maxwell
Well-known member
Do I need two inch on walls or one inch. Doing it this week or next
Highbeam
Well-known member
At least two inch. The sides are exposed to even a larger temp differential than the floor so the R-value is even more important.
I used 2" XPS on the sides and a sawzall to bevel the top at a 45 degree angle which allowed the concrete to extend to the wall. You can't even see the foam this way.
I used 2" XPS on the sides and a sawzall to bevel the top at a 45 degree angle which allowed the concrete to extend to the wall. You can't even see the foam this way.
OP
Dave Maxwell
Well-known member
My interior walls will cover any expose foamboard I hope
Highbeam
Well-known member
I did not bother cutting the top bevel on the foam in those areas that would be under walls though it wouldn't hurt anything. I only cut the bevels where the man door and garage doors would be.
The trouble is that I set the non-beveled foam so that the top of foam would be level with the finished floor. This made screeding the concrete a little tough because aggregate kept getting trapped under the screed board but above the foam. Not a big deal but a little attention was required.
OP
Dave Maxwell
Well-known member
Had thought about setting the foam board at one inch above floor height. Going two foot down. Is that enough? Forgot all about door ways and atuff
i was quoted $12,500 for a complete system 44x48. im looking at radiantec for the materials at $2,500 amd gonna do it myself. How much time to lay foam board down and install Pex?? I will be against the clock because of concrete pour shortly after construction starts.
Highbeam
Well-known member
One day for sure to go from a VB on top of the prepared subgrade to all foamed and pexed ready for pour. Really much less than a day.
KyleQ
Well-known member
I'm in MN and it gets decently cold here, I'm goign to setup for in floor heat and suppliment it with forced air and a/c. I've got 8-9' ceilings that will allow the HVAC to react quickly, allowing me to keep the floor temps lower.