Page 1 of 2 12 LastLast
Results 1 to 13 of 18
  1. #1

    Suggestions? 1070sqft Detached Garage heat & A/C in VA Ducts or Ductless? (pic)

    Hello,

    I'm looking for some help with my garage project. I've built an 1100 sq ft detached garage and I want it to be heated and air conditioned.

    I live in Virginia so we get 100 degrees in summer with very high humidity as well as freezing winters usually mid-low 30s but very occasional 20s - teens.

    I had been looking at a conventional Trane or Carrier heatpump setup similar to what is installed on my house. I have been talking with a few local HVAC installers about the project.

    One HIGHLY recommended that I consider the Mitsubishi "mr.slim" MINI SPLIT DUCTLESS system. I'm wondering if this would be a good choice for my application. I'm a little skeptical about it's ability to adequately heat this space in the winter, especially considering the concrete slab floor.

    My garage has 10ft ceilings on the left side and 13ft ceilings on the right, but is all one open space with no walls dividing. It will be well insulated and has insulated garage doors R17 if I remember correctly.

    This is going to be my "dream garage" and I want it to be just a comfortable as my house is. Any thoughts or suggestions for heating and cooling this space are greatly appreciated.

    Will a ductless system provide adequate heating and cooling for this space in my climate zone or would a ducted system perform better?

    Thanks,
    Chris


  2. #2
    Join Date
    Dec 2007
    Location
    Cedar Grove, Wi-Sheboygan
    Posts
    1,582
    with a nice big concrete slab you should have maybe thought about radiant heat, especially if you have insulated well in your walls and ceiling and put a good radiant floor heat in with a rigid foam bd. insulation on top of that would have been nice and cozy in there, and with all the proper insulation you probably would not have needed much for AC as well. Nothing beats Radiant H/C. My Shop here in WI is heated with a Hotdawg heater with walls and ceiling insulated and the floor has 1" rigid foam bd. on the floor and it stays right at about 45* with no heat and right at about 55* in the summer as I do not have AC for my shop, mind you this is just about 440sq ft. about half of what you have but it works well for me. Also this works because I keep my door's and windows closed in my shop year round even though I am tempted to open a window on those nice warm dry days I still keep them all closed. But If I would have been you I would have put in the Radiant heating for sure, you still can but I think it would have been cheaper to so so when you poured the slab.

  3. #3
    it's a little late for that...

    I would have loved to do radiant heat in the floor, it simply wasn't in the budget for me. I'm already way over budget as it is.

    frankly, a/c and heat is a luxury that I hadn't even planned on at this time, but I think it might be smarter to do before I insulate and sheetrock.

  4. #4
    Join Date
    Jan 2004
    Location
    PA
    Posts
    68,803
    A ductless will work fine.
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

  5. #5
    Join Date
    Dec 2007
    Posts
    96
    I have installed ductless systems in a few garages and have not had any complaints. It should work fine if sized properly.

  6. #6
    any more input?

    a competing local HVAC company (company B) called me back today with a price quote.

    while I had him on the phone I asked him about "company 1's" suggestion to use a ductless system, he said he DID NOT recommend it.

    he called it a "fancy window unit".

    any more thoughts on the subject?

  7. #7
    Join Date
    Aug 2002
    Location
    Office and warehouse in both Crystal River & New Port Richey ,FL
    Posts
    18,836
    Ductless will work fine for cooling ,but usually they no auxillary heat for the heatpump,so it might not heat it as warm as your home,if that's an issue.

    If you plan to di woodwork,or other messy stuff ,I go with conventional,and a 4" pleated filter ,over the ductless with a thin filter.

  8. #8
    Join Date
    Dec 2007
    Location
    Cedar Grove, Wi-Sheboygan
    Posts
    1,582
    If it were me I would go with a HP and air handler and just insulate the hell out of the shop, use a tyvek house wrap on the outside with some good insulation and get a small HP. Especially if your doing any type of woodworking as I do the dust no matter what you so it is never contained 100%.

  9. #9
    Join Date
    Jan 2004
    Location
    PA
    Posts
    68,803
    Quote Originally Posted by DanW13 View Post
    If it were me I would go with a HP and air handler and just insulate the hell out of the shop, use a tyvek house wrap on the outside with some good insulation and get a small HP. Especially if your doing any type of woodworking as I do the dust no matter what you so it is never contained 100%.
    Its already built.
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

  10. #10
    First of all, thank you for all of the opinions and input so far...

    yes, the garage is already built, but we did use a housewrap (typar) and I do plan to insulate it as well as possible. the walls are 2x6 studs, so there should be plenty of room for insulation, the doors are r17 insulated, and I assume I can insulate the attic space as much as I want or can afford to.

    I am concerned about the small filter area on the mini split ductless unit, the local contractor says It won't be an issue and that worst case I can just wash it out more fequently.

    I'm also up for opinions on the best types or methods of insulating the garage. batts or rolls versus blown in cellulose or foam or newspaper? any thoughts?

    the contractor trying to sell me the mr. slim says this:

    1. more affordable initial cost
    2. more efficient
    3. equal performance to conventional ducted heat pump

    the other contractor says I should use a conventional setup.

    BTW, the mr. slim guy is also a trane installer and is going to quote me a price for a conventional hp/air handler ducted install as well, but he seems to be really excited about the mr. slim idea...

    I'd love to save some money if the performance is truely equal, but I'm still skeptical due to my lack of knowledge of this "new" style of product.

  11. #11
    Join Date
    Jan 2004
    Location
    PA
    Posts
    68,803
    What are you going to use the garage for.
    Foam will increase air tightness. Lowering heating and cooling load.
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

  12. #12
    beenthere,

    the garage is going to be multi use:

    1. I'm an auto mechanic by trade, so I'll probably pick up a few side work jobs each month to help pay for the garage.

    2. One day I'll hopefully be able to afford another toy (race car maybe or restoration project). although between just building the garage, multiple house and yard projects, and new baby, I don't know how I'll ever afford ANYTHING EVER AGAIN

    3. I'm learning to MIG and TIG weld, so probably some of that.

    4. Plus I'll probably have a tv and a fridge out there and it'll be my personal relaxation area.

    so what I'm saying is mostly car stuff and general workshop, but also my "getaway".

    Foam will increase air tightness. Lowering heating and cooling load.
    Does this mean that "foam" is the best choice? Can I assume then that it's also the most expensive?

    thanks,
    chris

  13. #13
    Join Date
    Jan 2004
    Location
    PA
    Posts
    68,803
    Best choice is an opinion. It is expensive though.

    A mini should do fine. But as pointed ouot earlier, check to see what the lowest temp is that it can still heat your garage. Your contractor can telll you that.
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event