Floor Insulation for Shed Workshop

I just obtained a shed that will be my new workshop. It is 16x20 with 2x10 joists underneath and 1/2" plywood floor. It came pre-assembled (it was a display unit and the dealer was moving so I got it for a great price) so I was unable to insulate before it was fastened to the foundation. I'm wondering what would be the best way to insulate the floor? I see two options. The easiest would be to lay down 1" ISO sheets on the existing plywood floor and cover with 1/2" plywood or OSB. The drawbacks are that it only has 1" of insulation and I'll lose about 1 1/2" of interior height. The second option is to crawl underneath the shed and install 2-3" of ISO between the joists. This would offer me more insulation but will be a real pain in the butt to crawl underneath to install the insulation. I live in Northern Virginia and it can be very humid here, so that's a concern as well. Is there anything else that I should be considering? Last piece of information, I'm hoping to run electricity to it in 6 months to a year and then install a room-type air conditioner and dehumidifier.

Thanks, Bob

If you want to do it right start crawling. HD sells the insulation like Holmes uses and its water resistant. Stick that under it and staple on Tyvex and tape the seams. Its a pain but in the long run will work best.

You don't mention how much interior headroom you have.

Plenty of folks (myself among them) have a workshop in a basement with less than 8ft of headroom. I have about 7'7" and it feels fine and I'm 6'3". If I had 8ft of headroom in that shed I would have no trouble at all slapping down 2" of styrofoam on the floor and covering it with plywood. Quick, Easy, and lots of insulation.


(But I might still crawl under and run one or two outlets to the middle, depending on my shop layout! Hmm, you don't mention just how much crawlspace you have either.)

I might shoot it full of expanding foam insulation. Especially since its somewhat exposed, I like the moisture barrier.

I have seen some DIY kits online for this - not sure the economics but I do like getting it sealed to the outside elements.

Get a couple middle school kids to crawl under.
For pay, of course.

I live in Upstate NY and have a stick built 12'x16' shed that I converted into my shop. It was constructed (before I bought the house) on top of 4x4's on grade. It has a low ceiling - Its 8' on the outside and has a 1-on-12 pitch. I ran power out to it, put R-13 in the walls, R-19 in the ceiling, and wrapped it with vinyl siding. One thing I think is key is that the ground covers the gap on the ends of the 4x4's. creating an air space under the shop.

The floor was 3/4" PT plywood as a shed. I recycled laminate flooring from a room in my house (bad idea for a shop) and put it down with the standard thin foam under it. Laminate gets too slippery - but that's another discussion.

All I use to heat the shop all winter is an electric oil filled space heat set to low. Unless it is really cold for an extended period of time, the heater will keep the shop in the mid 50's. This warm winter it has been in the low 60's. If I feel it is cold when I go into the shop I will turn it up for a while. I do put a window A/C unit in during the summer, mainly to get some of the humidity out of the shop.

So, with that said, if you create an airspace underneath, and add a little flooring on top of (I assume) plywood, it may work. Oh, one note about a dehumidifier, it kicks out quite a bit of heat. I tried that, and it works great on cold, humid, days, but not so well in the summer.

Floor shading can be done with the help of insulation material, it will be great to look for such kind of implementation, as we have to put the money on such kind of service that will be ideal to carry the expenses in our limit.

Quote:

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Originally Posted by Chris Stolicky

I live in Upstate NY and have a stick built 12'x16' shed that I converted into my shop. It was constructed (before I bought the house) on top of 4x4's on grade. It has a low ceiling - Its 8' on the outside and has a 1-on-12 pitch. I ran power out to it, put R-13 in the walls, R-19 in the ceiling, and wrapped it with vinyl siding. One thing I think is key is that the ground covers the gap on the ends of the 4x4's. creating an air space under the shop.

The floor was 3/4" PT plywood as a shed. I recycled laminate flooring from a room in my house (bad idea for a shop) and put it down with the standard thin foam under it. Laminate gets too slippery - but that's another discussion.

All I use to heat the shop all winter is an electric oil filled space heat set to low. Unless it is really cold for an extended period of time, the heater will keep the shop in the mid 50's. This warm winter it has been in the low 60's. If I feel it is cold when I go into the shop I will turn it up for a while. I do put a window A/C unit in during the summer, mainly to get some of the humidity out of the shop.

So, with that said, if you create an airspace underneath, and add a little flooring on top of (I assume) plywood, it may work. Oh, one note about a dehumidifier, it kicks out quite a bit of heat. I tried that, and it works great on cold, humid, days, but not so well in the summer.

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I have the same setup...Built on site 12x16 made into workshop. I've not insulated it yet, but have two oil filled radiator type heaters, and dehumidifier.
Think next Spring I'll insulate it, but so far no issues.