Ceiling insulation and heating/cooling question

Reddinr

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My shop is about 1000 Sq. Ft with 10 feet from floor to the 2x10 ceiling joists. The 2x6 walls are fiberglass insulated and drywalled. The ceiling is a drop ceiling on the metal grids and includes a number of the 2 foot x 4 foot troffer lights. Above the ceiling is a 12/12 pitch roof and a storage space that is too big for my own good. I am finally going to insulate the ceiling and install better heating and cooling. If money were no object, (which it is but bear with me) what are some good choices for good, consistent heating and cooling in this situation (pacific northwest, west side of the mountains). Right now I have two vented propane fired blowers at ceiling height. They result in parts of my shop feeling like 95 degrees and parts feeling pretty cold. They really suck down the propane and are loud.

So, I want to add ceiling insulation. What type would you recommend? Faced or unfaced? I don't plan to heat or cool the attic space. I will have to install it by removing ceiling tiles, installing and putting tiles back in place. Should I also insulate the roof?

For the HVAC, is a mini-split with multiple indoor units a good idea or would a ducted system work better? I would need to run ducts in the ceiling. I plan to use electric power and get rid of the propane.

I do wood working and metal working. How do I deal with dust at the intake or at the indoor units?

Thanks for your thoughts on this.
 
I can't help on many of your questions but on the filters, plan to clean the intake filters often or remove the sawdust directly and probably still clean the filters often. I just installed a Mini-Split with two head units. One in a 17 x 45 garage with 20' ceilings. I have closed cell insulation on walls and ceiling. The second area is a 12 x 20 shop with batt insulation and sheet rock. So far the new system is working perfect. However it has not been much of a test yet because this is the beautiful time of year in Austin. Ask again in August.
 
Infrared tube heater


They heat up the contents of the shop, not the air.

For cooling it just depends on if you want the whole shop cooled or just a work area, I've gotten by with a regular window mount AC unit above my workbench. Mini-splits are great but only have experience with one in our bedroom.

Yes, insulate the hecck out of it. Will save money in the long run.

Also, if you're in an area where wood burning is an option wood stoves are great dry heat for cold damp days....

John
 
If possible I would look at spray foam on the underside of the roof. This may entail more work but better pay off long term. It seals as well as insulates. Any unfazed fiberglass product is just a air filter unless you can slow down or stop air movement through the batts. We learned that by using batts in the ceiling and then cover over top with house wrap, the house wrap can nearly stop the thermal siphon action that batts have. The house wrap does not have to be taped, just a good 18” to 2 foot overlap assuming it lays flat. It also then straddling the joints in the batts and reduces air leakage that way as well.

We have installed a 18K MRCOOL heat pump in our 1000 foot house, open concept, mostly for cooling but is used to heat along with a small gas fireplace. This replaces 2 window units and it is near whisper quiet. It is a DIY product and is not difficult at all.
The infrared tube heaters work great but will not control humidity outside of the heating season.
Pierre
 
Great information so far, thank you. I do want both heating and cooling although heating is more of the issue.
 
I agree that spray foam is the best. I find the best $ in ceiling insulation short of that spray foam is blown fiberglass. Your lumberyard should lend you the blower if you buy the bags from them. Use bats where you need access to the attic. I can't afford spray foam and have done a lot of that for other people that couldn't part with spray foam money. Also if you are considering mini splits remember my hvac guy said theyre disposable, not fixable. Something to think on anyway.
 
We've been through two mini-splits (both warranty repairs thankfully) for our bedroom, froze up and stopped heating. Might not be a problem if not using for heat in northern Michigan ;)

John
 
John - what brad were the mini-splits?
 
John - what brad were the mini-splits?

I think it was a Samsung but don't quote me on that. What happened was water got into the bottom and froze, wrecking the coils and leaving our room cold. The fix (which was done under warranty by our very competent local HVAC company) was to drill drainage holes in the bottom sheet metal and add a heating element. I really don't think I could fault the engineering or installation, just being on the windward side of the house and keeping our room at 68° F when it was 10° F outside was pretty impressive.

John
 
Since you have good ceiling support above the drop, you'd be best off to tear down the drop and put up plastic vapor barrier under drywall. Then blow in insulation (either kind) 12-16" of it. Then put up LED tubes for great light. I think this work would be worth more than any heating choices and far easier than trying to fit bats between all the wire hangers and other stuff which would leave all kinds of voids in the insulation.
Aaron Retired building contractor
edit: DO NOT INSULATE THE ROOF but make sure there is good ventilation in the attic. There needs to be air inlet and outlet. Usually the inlet is vented soffits and the outlet is (in order of desirability: on a roof that steep, ridge vent or gable vents but not both)
 
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