Suspended ceiling in garage?

[Burbman]

So the new 24x30 detached garage is complete. Plans called for 2x10 ceiling joists 32" OC so I have clear floor space with no lolly columns. The builder used 24' 2x10's, impressive lumber for sure.

Ventilated soffits combined with a continuous ridge vent will keep the place cool in the summer, but for right now it's very hard to heat. I need to insulate and drywall the ceiling and the walls.

I looked at strapping the ceiling, but that's a ton of strapping and would still be hard to staple in insulation. Another idea was to go in between the existing joists with maybe 12' 2x6's supported in the middle by the existing 2x10's, but not sure if a 2x6 would sag under sheetrock load over 12'.

There is only 3' or so from the top of the joist to the ridge, so not planning to use the attic portion for storage or anything else, the framing just needs to support the sheetrock.

Anybody install a suspended grid ceiling ("drop" ceiling)? Would have the added benefit of providing future access for wiring, etc.

 

[matt_i]

Sadly, the savings of about $150 to buy about 5 more timbers to have 24" o.c. is going to cost way more now.

The plan to hang 2x6s mid span and header the load to the 2x10s either side sounds like a good plan to me, other than getting a kreg jig and putting in hundreds (a lot) of 30-1/2" cross-span 2x4s as cross-wise supports. But you'd have to have a plan for the drywall so they could be found in meaningful areas.

The drop ceiling is OK but I don't think it really has much insulation value, like a single digit R value. I suppose theoretically fiberglass could be placed on top of the drop panels in short lengths as they are put in, but that's an itchy painful job if you ask me, and once setup like that would not be very flexible as far as running additional wiring.

 

[Franz1.0©]

You have sufficient structure to support a grid system, and you can use light weight fiberglass tile.
Most commercial buildings have no ceiling insulation beyond trapped still air between ceiling and roof. Few commercial roofs have any insulation.

Fire rated tiles should be available to provide the same fire rating as drywall.

 

[GMCGarage]

I would be careful of using the drop ceiling, the lightweight panels would be blown around when your garage door is open on a windy day.

You can check with your designer about using drywall, but i suspect the 24' 2x10 @ 32" oc would be in trouble for deflection at that span. Adding intermediate joists should be the way to go, get that trib area down to 16". Then you can get about 20psf out of the 2x10, which is plenty for drywall and insulation. Deflection will be around 3/4" to 1", which is borderline for drywall.

 

[EnduroRdr]

If you are planning to hang Sheetrock/drywall boards on ceiling, I think I'd just fill in the spaces with more 2x10 so you end up with 16" on center.
That Sheetrock is heavy, also if you store anything up top later (think Christmas Trees etc) you will appreciate all the joists being same height.


Sent from my iPhone using Tapatalk

 

[tcianci]

Add an intermediate 2x10, get the ceiling joist spacing back to where it should have been to begin with. This will give you a good frame for hanging drywall and Conventional spacing for insulation. Besides, drywall is lots cheaper than drop ceiling.

 

[FJ 432]

I have a friend who received a demo'd grid ceiling and used it for his garage. 16 foot height with a 3 foot plenum. I think it looks good for free and it does provide access.

 

[Burbman]

So the existing 2x10s are meant to serve as collar ties per the design, not joists, and so there is one every other rafter. I never spec'd a ceiling when the plans were being drawn because i figured "no big deal" to add sheetrock later. Doing some research and it looks like I would need to add 2x10's just to carry the weight of the rock. Since I can't get a full 24' in there now that the roof is on, can I get 2 16's and overlap them in the middle? If I nail them generously that should enable the scabbed joist to carry the load of the drywall.

The problem with this plan is that I have 11 bays to fill, so that's 22 16' 2x10s.....plus a lot of grunt work getting them hoisted up there and nailed in.

I did get the heaters installed last weekend, a pair of 5kw King electric ceiling heaters. I was able to get the garage comfortable with no insulation/drywall at all, so I don't need a super insulated ceiling, just something to block the convection of the heat up and out the ridge vent.

I need something light yet stiff enough to carry a 32" span without sagging....corrugated tin?

 

[ard]

You sure you can't get a 2x10 in, ends properly trimmed, but flat- slide it into the eave, then up onto the opposing top plate and stand up?

Do it once, do it right. Put in the joists, hang rock, blow in bales of insulation from Home Depot (or staple batts from below)

 

[Dr Stan]

What would be the price of sprayed on insulation?

 

[James-W]

Am I to understand your rafters/trusses are 32" on center? I never heard of a garage/workshop with that spacing before. In a way it doesn't make any sense because of the dimensions of sheathing material.

 

[EnduroRdr]

You sure you can't get a 2x10 in, ends properly trimmed, but flat- slide it into the eave, then up onto the opposing top plate and stand up?

Do it once, do it right. Put in the joists, hang rock, blow in bales of insulation from Home Depot (or staple batts from below)

Agreed: ard is right!

if you trim the ends (cut corner down to fit pitch of roof where it sits on walls) you should be able to slide in from below (living space) laying flat one end first a little deeper so other end will clear. Then once it is centered stand it up. I did this myself to increase load for attic storage. My joists were 2x10 on 24" center, I added another from below in each space so then I had 2x10 on 12" center. To increase load and support decking in attic for storage as well as Sheetrock on ceiling below.

As suggested previously, don't cobble it, do it right and add the 2x10s to match existing joists. You will end up with 16" OC which is needed to support the weight of the rock.


Sent from my iPhone using Tapatalk

 

[Burbman]

Am I to understand your rafters/trusses are 32" on center? I never heard of a garage/workshop with that spacing before. In a way it doesn't make any sense because of the dimensions of sheathing material.

Nooo....Rafters are 16" OC. Collar ties are on every other rafter.

 

[ishiboo]

You have sufficient structure to support a grid system, and you can use light weight fiberglass tile.
Most commercial buildings have no ceiling insulation beyond trapped still air between ceiling and roof. Few commercial roofs have any insulation.

Fire rated tiles should be available to provide the same fire rating as drywall.

That sounds highly dependent on your area. Here commercial roofs use foam insulation under it, and the foam is also how they pitch the roof to the drains. Below the roof, there's rolled fiberglass.

Given the climate in OP's area, I think expecting to heat it without insulation would be a huge mistake.

 

[ishiboo]

I think over time, 2x10 collar ties at that span is going to sag in the middle with 5/8 drywall. You would need to basically turn these into trusses by some vertical members even if you added the "missing" ones.

What about liner steel? Like metal roofing/siding but it's thinner for ceiling use so it's less expensive.

Or PVC with the same profile: https://www.menards.com/main/buildi...-interior-pvc-liner-panel/p-1444448497530.htm

Or flat PVC: https://www.menards.com/main/paint/...0-pvc-interior-wall-panel/p-1444437134111.htm

(NOT 100% sure ISpan will span the 32" without sagging. You'd need to check that!)

 

[Franz1.0©]

That sounds highly dependent on your area. Here commercial roofs use foam insulation under it, and the foam is also how they pitch the roof to the drains. Below the roof, there's rolled fiberglass.

Given the climate in OP's area, I think expecting to heat it without insulation would be a huge mistake.

I'm sitting on the South shore of Lake Ontario, and you're sitting on the frozen tundra, the OP is on Tropical Longgggggg Island.

Roof insulation on commercial structures here was and still is hot tar and gravel other than new & rebuilt roofs in the last 10 years. Most insulated roofs are more a function of using the above ceiling space as an air handling plenum. Dead air space in and of itself is a wonderful insulator.