heating suggestions

[bowslam]

I have a 45x85 pole barn, with a 20x45 section that we've insulated as a year-round shop. Looking for heating suggestions. I live nearby and don't always get over there every day. But I'd like to keep it 45-50F during the winter with the ability to kick it up fairly quickly when wanting to spend more time there. I do have electric, so that's an option although probably not the most economical. Thanks for any ideas....

[wjmst]

There are many options to choose from, most of them depend on price. You probably want something you can set with a thermostat, an oil or propane furnace would work, but you would have some money tied up in to it. There are also many different types of propane burners that will heat up an area quickly.

Wes

[GaryM]

Do you have propane available?

There are basically two types of heaters. Those that heat the air, then the air heats the surroundings, and these that heat objects directly. The second type are called radiant heaters. You've probably seen them in the box stores, often located above their loading dock doors.

As they heat objects directly they don't have much of a lag time. I believe they can be thermostat controlled.

Here's a link to the type I'm thinking of: Detroit Radiant

[Pat]

Radiant is definitely better than any kind of forced air in this application.

Radiant doesn't take as big of an efficiency kit due to infiltration. You can even make an outdoor region comfortable (like the loading dock example of Gary's.) I have a propane fired "mushroom" heater. No, not for heating mushrooms but shaped like a mushroom. If you are seated at a table or bench under the mushroom you can be toasty warm even where without the heater you would quickly develop hypothermia.

Radiant heat definitely can be controlled by thermostat. In outdoor installations or where there is abundant infiltration a thermostat can be installed to control the radiant flux rather than the air temp. I have 5 different zones in my new house that each has its own thermostat for controlling the radiant heat. One of them controlls the temp of a tile covered wall and the rest control the air temp in the room. I have a mix of radiant floors, ceilings, and even walls (shower, the tile covered example).

[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]

[CJDave]

[img]/forums/images/icons/tongue.gif[/img] The neighbor has a big shop about 40 X 60. When they poured the floor they installed loops for H.W. heating. He finally got wealthy enough last year to get the hot water heater so we installed it sometime in January. Once it got everything up to temp, it took very little heat input to hold the temp where it was real comfy. If your floor is already in place, you might think about using some moveable stand-up quartz heaters to warm YOU instead of trying to really get the whole place comfy. After trying various things from ram-jet heaters to propane radiants, portable quartz is what I ended up using in my uninsulated truck shop in far-off California. And yes, winters in CA can be cold and clammy. It's the coldest 34 degrees that you'll ever experience. It might be a dry heat out there, but it is a WET cold. We are going to be busting out the floor in our 14 X 32 shop here in Iowa and when we do it will get repoured with the hot water piping in there. We have forced air and air conditioning in there now, but the slab is terrible. [img]/forums/images/icons/tongue.gif[/img]

[Pat]

CJDave, since you are going to get a fresh start with the floor slab, this is your chance to insulate it. I recommend as a minimum that you put down one of those aluminized bubble wrap blanketsand also insulate the outside of the footer etc. to avoid thermal wicking out into the cold wintertime soil.

More costly but a good performer is a couple inches of rigid foam insulation under the slab and around the periphery. Some folks just insulate around the periphery and let the dirt under the slab contribute to the thermal mass. It sorta works but is not to my personal preference.

Be careful where you buy your PEX. A lot of it is not UV tolerant and should not be stored in sunlight for any appreciable time. Plenty of folks along the supply chain don't know or don't care and you can't tell by looking so be a bit cautious.

[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]

[CJDave]

[img]/forums/images/icons/tongue.gif[/img] I'm printing out your commentary, Pat, and adding it to my folder marked: Granary-To-Shop Conversion Project. Thanks for the good info!!! [img]/forums/images/icons/smile.gif[/img]

[Pat]

CJDave, Feel free to PM me regarding any topic if you think it would be too boring to carry on in public.

Let me remind you that in-slab hydronic heat is NOT an economical heating solution for a space that doesn't have a fairly high percentage of occupancy. It takes a LOOOOONG time to get the slab up to temp and it takes a long time for it to cool down. There is no "night time set back" strategy. You will be paying to heat the space 24-7 whether it is occupied or not.

I have some in-slab hydronics and JUST LOVE IT but it is my great room, master bath, and shower. The shower is actually "ON" for a few hours twice a day (preferred bathing times) but is comfortable enough the rest of the time. My shop is two story and zoned separately so I can, for example, heat the ground floor and not the upper floor (when unoccupied.) The shop has forced air heating via heatpump (provides A/C in summer.) If I had it to do over I would lean more toward radiant ceilings for heat. Although I am interested in radiant cooling, it is more of a theoretical exercise or mental gymnastics than an actual installation.

Oh by the way... Radiant ceilings (in drywall type construction) typically have much less thermal mass than in-floor radiant in slabs. I have three rooms with in-ceiling hydronic heat and they are much faster in response. They will heat up and cool down very much quicker than the slab and so are more practical for spaces with irregular usage patterns although mine are the master bedroom, utility room, and hall bath. This is not to imply that they aren't just fine for frequently occupied or continuously heated spaces. I just set the T-stat and let it go but you could use a setback stat with any lower thermal mass system.

I have never owned but have admired the rather long gas fired overhead radiant heaters with parabolic reflectors. I don't know their combustion efficiency but they sure make efficient use of the heat once produced. I have seen them used in outdoor spaces to make a glove free work area in rather cold weather. Even where exposed to wind they still work well since the radiant heat is delivered as IR and can't be lost in the wind.

When it comes to heat sources, you pays your $ and takes your chances. Electric resistance heat is probably the most expensive to operate and the cheapest to buy (not recommended.)

Heat pumps only cost about 1/4 to 1/3 as much as resistance heat to operate but equipment, distribution, and installation are more expensive. When I was buying for my mom's house the breakeven on a high SEER heatpump vs electric heat and A/C was less than 3 years after which the low operating costs have been $ in the bank.

If your temps go below about 40F very far, very often, or for very long then you need some other backup heat besides resistance heater strips in a heat pump. Gas fired backup is the simplest of the "GOOD" solutions.

You could just "SHUCK" all this engineering and get one of those kits with cast iron parts to convert a metal drum to a wood burning stove. I suggest the "improved" model that has a second drum atop the first as it extracts a lot more heat from the fuel. To calm your environmental concerns, get one of those catalytic thingies that go in, I think, the exit flue of the lower drum. (Perhaps a knowing person will correct me.) This seriously reduces the unburned components of the effluent stack gasses and boosts the efficiency.

[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]