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New workshop- Help with options

RichK Member Posts: 2

I'm building a new 28'x44' workshop in NJ, about 90' back from the driveway and house.

Since it's new, I figure running radiant in the 4" slab is the way to go (with 2" foam underneath and around the slab sides) and also underneath the second floor between joists. Building will be well insulated, but only plan on keep around 60 degrees in winter at most.

My struggle is in deciding how to heat the water and the fuel for the boiler/water heater. I'm looking for simple. Something that direct vents (or horizontally vents to outside wall?) would be best so I can be spared from installing a chimney.

I have natural gas at the house, but fear the gas company will require major upgrades, new meters, plus the expense and disruption of running a line from the house all the way to the new building. So I was looking at alternatives like pellet boiler or oil instant hot water heater (Toyotomi OM-148) as alternatives. Each have thier own advantages and disadvantages. I have a small room underneath the stairs going to second floor where I could potentialy place the oil tank.

Any thoughts from the fine folks here?


  • JeffBrown
    JeffBrown Member Posts: 67
    how about

    electric boiler or hot water heater?  pretty darn simple and NO venting requirements!

  • JStar
    JStar Member Posts: 2,752

    Air to water heat pump? Could also run a chiller for radiant cooling!
  • RichK
    RichK Member Posts: 2
    Would electric be ridiculously expensive?

    I'm ok that it's "more" expensive, but if 2 or 3 times more than pellets/oil, maybe not worth it? I dunno....
  • JeffBrown
    JeffBrown Member Posts: 67
    you'd have to

    run your own calcs based off of your current elec/oil prices to see how they compare.

    How about propane?
  • heatpro02920
    heatpro02920 Member Posts: 991
    I would

    run natural gas from the house, you can get a sprinkler company to trench for you cheap, lay in the pipe, tracer, warning flags, get a couple risers, and if the meter needds to be upszed so be it...

    For a boiler you can use a Rinnai rl80 to heat the water, I have a bunch of rinnai tankless powered radiant systems out there, they tend to work great...

    Buy once cry once....
  • Snowmelt
    Snowmelt Member Posts: 1,414
    edited April 2014
    What you want

    You want to run gas to the garage. I am from nj I did more then my shares of these type of jobs.

    after you get gas to the garage you will want a very small in btu's a peerless boil,

    Or a htp product versa- hydro

    Or navien or takagi or Rinnai tankless

    Don't worry about the gas that much the gas company will up grade your gas meter for free, they want you to spend more money in gas.

    Or a.o. Smith cyclone btx 80

    Most of these can be vented with 2 inch pvc

    Or pvc type product
  • JStar
    JStar Member Posts: 2,752

    They will upgrade the meter for free but the 100ft of gas line might be tens of thousands of dollars.
  • Rich_49
    Rich_49 Member Posts: 2,766
    edited May 2014

    is your supplier , NJNG , PSEG ,etc ?  

        Gas line only has to be sized for the appliance installed in the garage , thi sis supported in 402.5 of the IFGC , allowable pressure drop .  The line you actually require need not be huge as most contractors will tell you . Of course this all depends on which utility supplies your fuel . NJNG for the most part utilizes an 8" w.c regulator allowing smaller pipe to be used as opposed to PSEG's standard 6-7" regulator that is not as forgiving . 

      As far as rates ,  go here is the real math between electric and gas  

    Gas  = 1 therm = 100,000 BTU = app 1.00 per therm .

    Electric ( using an H heat pump with COP of 4)

    Kw = average of .14 = 3414 BTU (29.29 Kw = 1 therm)  .14 x 29.29 = 4.10 .

    Gas and electric , taking into consideration you can make a COP of 4 based on system design are about equal . 

     Odds are pretty good that the installed meter is sufficient to support the added load for the garage . If you are insulating well you can probably use low water temps . If the intend on having a bathroom there also my suggestion would be to use a good quality tank type water hater that is rated to also supply space heat ( HTP versa flame , AO Smith vertex ) . HTP will be easiest to plumb and less expensive all taken into account .  This type of appliance will if programmed properly give you outdoor reset for your space heat , all the DHW you will need for one bathroom , and plenty of mass to eliminate the short cycling you are likely to suffer from a small load profile .   J star also has a good point , for a garage you will probably only need a good whole house de humidifier to accompany the radiant cooling , check out the Ultra Aire SD12 , it will remove up to 180 pints of moisture per day , has 4300 BTU of sensible cooling capability and will introduce fresh air also .  That would be real nice , imagine wanting to be in your garage more than in your house .

    Where are you located in Jersey ?
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • Dave H_2
    Dave H_2 Member Posts: 553
    Existing heat source

    What do have for a heat source in the house?

    If you already have a boiler, it may have enough horsepower to heat both the house and the workshop.

    You might want to look into preinsulated/jacketed pex systems like Ecoflex to run underground. Eliminate the venting at the workshop, running gas lines, new meters......

    and since you were going radiant, the water temp can be lower in the pipe and lower any losses you could experience

    Dave H.
    Dave H