In-floor Heat for 9600sq.ft.??

[jkidd_39]

I am building an 80x120ft shop w/ a 30x75ft loft upstairs. Walls will be 18-20ft tall to give me lots of loft height as well as eventually storage on the sides.

The building will have 45x80 open end where a 5ton crane will be.

I want to use infloor heat through out the whole building. I want to be able to turn off zones in the building incase we are working under equipment to stop the "hotbox" effect.

I'm very new with this project and I am trying to get as much info as possible.

1. Has anyone built this large of a system?

2. I would like to use logs/pellets wood fuel to heat the floor. Anyone point me towards some good units/systems?

Thanks alot guys and any other useful info please throw it in.

 

[stingry]

I want to use infloor heat through out the whole building. I want to be able to turn off zones in the building incase we are working under equipment to stop the "hotbox" effect.I'm very new with this project and I am trying to get as much info as possible.

Not sure what the "hot box effect" is but infloor radiant heat does not lend itself to turning itself on and off. If you turn off a loop, the floor is going to remain warm due to the thermal mass of the concrete. The beauty of infloor radiant is having warm floors to do work at floor level, not sure why you would want to "turn it off"!

 

[jkidd_39]

The hot box effect is being under a truck with the floor on. It traps the heat and makes it very uncomfortable.

I understand the floor doesn't cool off fast but it would be one of those things where we plan the spot and turn off one zone hours before.

Thanks for the reply


Sent from my iPhone using Tapatalk while pulling a 36ft gooseneck and not paying attention to the road.

 

[tdkkart]

The hot box effect is being under a truck with the floor on. It traps the heat and makes it very uncomfortable.

Very likely a myth that came about years ago when radiant floors were in their infancy. Unless you intend to run your room ambient temperature at 100*, the floor will never be hot enough to be "uncomfortable".

As you study some more you will learn a few things.
1st you'll find that depending on the heat loss of your building, your floor will likely only be 5-10* warmer than your room air, which means that even if you keep your room temp at 70* your floor will only be 75-80*, far from uncomfortable.

2nd thing you learn is that you won't have to run your room ambient air nearly as hot as you do with other heating systems. More than likely anyting above 60* or so and your employees will be overly warm unless they're working in shorts.

You'll be alot more successfu at this if you don't go into it with a bunch of pre-conceived notions caused by myths.

 

[sr71]

...Can't see why this would be a challenge for a pro. Just lots of zones. I have it throughout my home - 4 zones ......best heating you could ask for. if I build another home/garage they will both be radiant - as well as the driveway.

 

[jkidd_39]

The one shop I worked on trucks in w/ a heated floor had this problem.

Although I do not know the age of the system.

I figure it's only ball valves on each circuit.

Thank you for the input.

Any more info would be greatly appreciated.

Right now my old shop has absolutely no heat. So as of now we would be happy with a cold shop with floors that don't require cardboard to stand on in the winter.

I don't plan on heating the shop anywhere near those temps. I figure a thermal tee or a hoodie and stocking cap in the winter will be just fine for us. Maybe 5-6 years down the road we can consider getting a furnace for the shop. Only the loft and break room will have heat other than infloor.


Sent from my iPhone using Tapatalk while pulling a 36ft gooseneck and not paying attention to the road.

 

[CARS]

There are a bunch of farm shops around this area that are that big (or bigger) with infloor. Haven't had the jewels to ask what it costs them to heat it.

I am under cars most of the day and I have never noticed heat being trapped. In fact, one night after having too many after work I just layed a sleeping bag down on the floor and passed out. I was waken by the pumps turning off and the slab cooling down. Was a weird feeling.... hot, cold, hot, cold.

Now I have worked in shops with tube heat. Working under cars with that style heat really sucked in winter. The surface of the car would get warm but the cold metal under the car kept it cold under the hoist for along time.

 

[tdkkart]

There are a bunch of farm shops around this area that are that big (or bigger) with infloor. Haven't had the jewels to ask what it costs them to heat it.

Well, let's see, 9600sq/ft is my 1200sq/ft x 8. I heat mine with a 7KW electric on-demand heater. 8 x 7KW = 56KW. 1KW = 3415 btu, so 56KW = 191,240 btu's.

I know that I've killed nearly $200 worth of electricty in one month, 8x that is $1600.......
Propane would be close to the same money.

IF you could do it with natural gas you're still talking $500ish/month.

 

[theoldwizard1]

My biggest concern with heating that large of an area with wood/pellets is feeding the boiler. This will probably make wood (logs) impractical. You are going to need a very large hopper/feed system and will go through more than a ton of pellets in a season so be certain you have a good supply source nearby.

I would investigate a dual system. Pellets and gas/oil/electric as a backup.

Check with the experts about temperature sensing/regulation. They would also likely tell you NOT to completely turn off an area. Just turn down the thermostat for that area.

Besides in floor radiant, you may need some kind of forced air radiators, especially near large doors.

 

[nehog]

Well, let's see, 9600sq/ft is my 1200sq/ft x 8. I heat mine with a 7KW electric on-demand heater. 8 x 7KW = 56KW. 1KW = 3415 btu, so 56KW = 191,240 btu's.

I know that I've killed nearly $200 worth of electricty in one month, 8x that is $1600.......
Propane would be close to the same money.

IF you could do it with natural gas you're still talking $500ish/month.

I gotta agree. My buddy, with about 1800 sq ft, burns about 650 gallons of oil a year heating to 70 with slab heat. For one the size you envision, that could be almost 3500 gallons per season (at $3.60 a gallon, a cost of about $12.5K! Ouch...

BTW, his floor is not too hot to work on, it is perhaps a few degrees warmer than the air temp (keeps it at 70) but overall, very workable.

 

[Mr onetwo]

You are out of your mind if you don't get a very reputable and experienced infloor installer to help you with this project.Get references and visit other buildings.You will be very sorry if you don't.I have over 25 years in the trade and have been involved with some huge projects(airplane hangers,ect.) this is not a DIY type situation IMHO!You should also investigate using an "air rotation" system.

 

[Jackfre]

...Can't see why this would be a challenge for a pro. Just lots of zones. I have it throughout my home - 4 zones ......best heating you could ask for. if I build another home/garage they will both be radiant - as well as the driveway.

I did snow melt on my sidewalks. North facing and lots of elevation change, so a pain to clear. Once I put in the snow-melt, I loved looking out the window the morning after a storm and seeing 2' of fresh snow and dry sidewalks Doing a driveway is a whole different kettle of fish from an expense standpoint, but doing the apron in front of the garage is a good idea. This is probably one of the best uses for solar thermal.

 

[jkidd_39]

You are out of your mind if you don't get a very reputable and experienced infloor installer to help you with this project.Get references and visit other buildings.You will be very sorry if you don't.I have over 25 years in the trade and have been involved with some huge projects(airplane hangers,ect.) this is not a DIY type situation IMHO!You should also investigate using an "air rotation" system.

I will be using a professional. I am simply learning the in's n out's of the system.

I have found that the house building/ construction folks in my area have a very "my way or no way" approach.

Ask a guy selling wood log furnaces about his units. His reply is mine is the best. Everyone else (propane, Elec, wood pellets) *****. Same for everyone else.

I'm just learning. I have a basic game plan but I am using you guys to gauge how realistic my plans are.


Sent from my iPhone using Tapatalk while pulling a 36ft gooseneck and not paying attention to the road.

 

[Galaxie]

Ours is 6400sq/ft, every loop has a valve on it, haven't done any under vehicle work yet, only had the heat going 2 weeks. I was surprised how fast the room warmed up, was expecting several days and it took less than 2 to get in the mid 50's. Ours is propane so I couldn't comment on pellets, so far been very pleased with how little fuel it uses and how fast recovery is after a door is open.

 

[Bigrhamr]

Take a look at http://garn.com/ for a big wood fired boiler with built in storage. Big bucks but you can also add storage tanks to a different boiler.

And, check out http://www.hearth.com/econtent/index.php/forums/ and go to the Boiler Room for lots of wood fired boiler discussions and resources.