Material ideas for finishing between joist bays?

[cmandp]

Hey all. We have been working on removing the homasote and nasty fiberglass insulation that was put up on the ceiling of the back section of our garage. This is so we can remove old dangerous electrical and eventually rewire outlets and new LED fixtures I got.

The back section is roughly 7ft from floor to bottom of joists, so pretty short. Call us crazy, but my wife and I are thinking if we leave the joist bays open and add something white to the underside of the upstairs subfloor between each joist, it will feel more 'open' with such a low ceiling height. It will also keep the dust from upstairs from raining down on my shop area down there. Planning to run new circuits in conduit so it can be changed as time goes on. Lights will be mounted to bottom of joists.

I wanted something that isn't going to require tons of time, it is just a shop area. Ideally there would be some cheap white material on a roll that I could cut to length and just stick up there for now (wishful thinking). Other thoughts (with better construction technique) were doing metal siding panels or some kind of pre-painted hardboard/MDF even drywall ripped to width and perhaps just tacked up there on some ripped down 1x or 2x nailers.

Here's a poor picture of the (saggy built up 2x6 I probably need to fix) which shows the area. Its roughly 20X25 with that beam running the 25ft length down the middle.



Thoughts, suggestions?

 

[fourjeepin]

I’d either put up metal roofing or just paint it

 

[Leaflessshadetree]

Drywall or metal.

 

[billconner]

I would want something prefinished and installation that didn't show irregularities nor fasteners. Was imaging some little angles that attached to joists, leg up for fasteners, and a slightly to flexible panel that slides in. Maybe just mill - table saw - small strips of wood. I found some drywall products for 40¢ foot but that's still high. I am thinking a neat, clean, uniform look and low labor. Something smaller than a 1x1 that you could install with a laser line and brad gun.

 

[Raisedonadeere]

I'm thinking, if you want to keep the joists exposed, then staple strips of the 3/16 plywood used for underlayment on linoleum floors, then paint it and the joists.

 

[WisJim]

I had a similar ceiling in a building on our farm some years ago, and we broomed it clean and sprayed cheap white paint with an airless sprayer. We got a clean white ceiling that really brightened up the area and encouraged me to pay more attention to cobwebs and dust. But in your situation, it wouldn't stop dust from the upper floor.

 

[dave*99]

Perhaps buy some 4x8x1/2" Styrofoam sheets, rip into bay width strips and push them up into the bays? I like the paint idea better but as mentioned, dust will come through that.

 

[driftpin]

I used masonite on the bottom of mezzanine floor joist bays, cut so the bays make open-ended boxes for storage of things. I use it for electrical supplies, Simpson Strong Tie brackets, and misc. things I want to hang-onto, until I need them. I bought translucent plastic bins at Harbor Freight, they're just the right size to fit into the bays. I use masking tape to write-on to I.D. what's in the bins.

I agree that the easiest thing to do would be to spray paint it white. You could put masonite inside each bay, to stop the rain of dust. Maybe Liquid Nails, and some grommets with short screws maybe 1-1/2' apart down the sides? Fastening the masonite to the underside of the above floor's sheathing.

 

[mike93lx]

I'd probably do the painted underlayment ply, attached with a few spots of construction adhesive and some 16 gauge brad nails. Then paint the joists

 

[rancherbill]

... Call us crazy, but my wife and I are thinking if we leave the joist bays open and add something white to the underside of the upstairs subfloor between each joist, it will feel more 'open' with such a low ceiling height. ...

You're crazy. You'll be paying for heating or cooling forever. The space above will be more comfortable with an insulated floor.

Honestly, with the world changing with climate change you need to cut down on energy use.

 

[4x4Pete]

I'd put a nice coat of white paint on that ceiling joists, subfloor, everything. For upstairs, a roll of vinyl flooring upstairs or more paint. Paint seals up dusty stuff pretty good.

 

[Shiftless]

Do you heat that garage? What is upstairs that generates so much dust?

As far as lighting goes, In my garage, I too have a low ceiling and open ceiling joists. I installed 4 foot long twin tube LED fixtures up in between the joists. It‘s better to not have anything hanging down below the joists.

 

[cmandp]

The upstairs is currently not finished, just the subfloor except for the ceiling which does have insulation. That will all need to come down and is slowly dropping dust.

This back section is concrete block. I'd eventually like to insulate all of the walls and redo the insulation in the ceiling on the 2nd floor. The plan is to heat and cool the entire garage with mini-splits. I can imagine how insulating these joists would probably help with heating and cooling cost. You could maintain just the space you're using.

Thank you for the suggestions so far. I will certainly take just painting it into consideration. I wasn't sure how far fetched it would be to glue and tack a thin material to the underside of the subfloor either. Bit some of you seem to have the same line of thinking. I doubt we'll be doing any kind of nail down flooring up there.

 

[NUTTSGT]

Fiberglass between the joists and 3/4" foil faced poly-iso foam board on the bottom of the joists.

 

[billconner]

Correct me but plan is to condition both basement and floor above, correct? If so, I don't see the case for thermal insulation between them. Now, if basement is shop and floor above living space, what you're planning will have no acoustical isolation. Every shop noise will be clearly heard above.

 

[Stuart in MN]

If this is a garage underneath living space, it really should have a fire barrier on the ceiling like the appropriate thickness of drywall.

 

[Fixr]

Fiberglass between the joists and 3/4" foil faced poly-iso foam board on the bottom of the joists.

I've seen foam board with a white facing(with printing). Might be a decent quick and easy compromise stapled right up against the subfloor to retain usable space between the joists.

 

[Tbender78]

How about the cheap fiberglas drop ceiling panels? They are cheap, easy to cut, and provide some insulation. They are 24”x48”x1”. You could cut them a little wider than your joist and wedge them in place. One side is already white.

 

[cmandp]

The back part in question is two levels, with a structural wall splitting it in half. First floor is ground level.

Front is wood framed single story with 10' ceiling, slightly smaller footprint than the original back.

No living space in there in the plan right now. In the future we would like to do it but only once ADUs are allowed.