Tight Attic Access Panel

[johnharris]

To cool down the garage I'm adding 7/16 OSB to the truss bottom chords. Adding a ceiling the soffit and ridge vents can now do their job. Was way too hot the first summer of this garage I built this past winter. Having fink trusses that are 16" on center I only see the option of making an access panel. I've only seen pull down ladders made for 24" on center. As you well know I also cannot cut the bottom chords to box it out. I plan on making it close to the fink chords. I can pull myself up easily with those and the nearby bottom chords braces also give it strength.

Should I just make a 16 x 32 panel out of OSB to just push upward? I've given thought of making a hinged pull down 16 x 32 panel? Whichever I will box around it with 2x4s.



As mentioned earlier I'm making the ceiling using 7/16 OSB. In other threads I read tips on using 1 5/8" screws and Alex Plus caulking. I got 1 5/8" cement board screws. They are star headed and cost only $32 for 575. I'll last roll on 2 layers of Kiltz Sealant.

 

[Dig Doug]

Frame a small box below the bottom cord for a pull down ladder
let the box hang down Far enough for the fold out ladder, center the ladder on an open bay.

 

[johnharris]

Frame a small box below the bottom cord for a pull down ladder
let the box hang down Far enough for the fold out ladder, center the ladder on an open bay.

Where can I find a folding ladder only 14" wide to fit between those 16" on center bottom chords?

 

[johnharris]

Forgot to mention nothing will be stored up there. I'll rarely use the access panel. Just need to reach the wires and blown insulation in the near future.

 

[mikegt4]

When I built my house (1990's) the building code for attic access opening width was the distance between trusses set at 24" c/c and a minimum length that I don't remember, probably still the same today. Supposedly the minimum that a firefighter with an oxygen tank could fit through.

 

[Dig Doug]

You make a box like a small soffit ( to fit the ladder size ) that hangs down below the bottom cord of the truss.

 

[Dig Doug]

If your not going to use it often just do a push up panel, that’s quick and easy!

you might want to get a couple sheets of ply wood up there just in case you want to store something in the future or at least cat walk to access the gable ends maybe need a gable vent fan ….

 

[johnharris]

I'll probably just make a small push up panel. Instead of OSB I'll make the panel out of sandwich 3/4" plywood I have left over.

I will leave a few 12' long 2x10 walking planks on both sides to make walking on those bottom chords easier.

 

[Norcal]

As those sheets of OSB are hung those cockeyed sheets are going to bite you in the ****, it's very important to get the starter sheets straight, it will only get worse if not corrected, if working solo might be worthwhile to rent a drywall lift & even if help is available still might make the job easier. As to attic access frame out your opening and if you have a table saw rip some OSB in 1 1/2" strips to trim out the opening then cut a sheet of 7/16" OSB to fit the opening, in my part of CA it is normal to do that with drywall for the attic access.

 

[slimpickins]

Where can I find a folding ladder only 14" wide to fit between those 16" on center bottom chords?

How tall is your ceiling? In a previous house I owned, I made my own ladder to fit between the joists with some good 2x4's and hinged it to the bottom chord with 1/2" lag bolts. You could use 2 x6s as well if you have a tall ceiling. I made my ladder so when it swung down, a cable pulled the lid up and the ladder was 3 feet taller than the ceiling so when you climb up, the ladder extends above the ceiling, making it easier to get into the attic and onto a support platform. When the ladder folds up it fits between the bottom chords and is flush with the ceiling. If you really want to go all the way, add a cable and spring system to make the ladder easier to fold up against the ceiling, or else just a rope and pulley system to raise/lower it. Install a good latch so it won't fall on you head!

Where do you live? Do you need a vapor barrier above the 7/16 OSB or are you going to rely on the paint? That would never work here where we get -40C temps in the winter.

 

[Innovate1]

Where can I find a folding ladder only 14" wide to fit between those 16" on center bottom chords?

You don't need to fit it between the cords if it sits BELOW them. But you would need to frame a wider box below the existing cords and make that tall enough to hold the folded ladder. Seems like overkill for occasional access.

If you make a push up panel then whatever holds it up will have to be slightly narrower than the existing opening unless you support in only on the ends. 1/2" on each side means you only have 13.5" left. Single layer 3/4 plywood would be plenty stiff to support only on the ends but would leave some air leakage on the sides. You could also make it hinge down and keep the full 14.5" and put some foam tape around the edge if you wanted a good seal.

 

[NUTTSGT]

Sir, you need to have the end of your sheets break on a truss. If you don't they will sag over time and pop out any caulk/paint. I've hung 7/16 OSB on the ceiling by myself, had but not impossible. As mentioned above, use a drywall lift to make life easier.

Two coats of Kilz oil based will work great but still needs top coated or it will yellow over time.

Simply make a push up attic access panel. If your trusses are 16" OC, that's fine but I suggest making it 48" long. Easier to frame up and cut a strip from a full sheet. Just use some 1x4s to frame the opening and allow 3/4" hangover to hold the panel in place. Once done, you can insulate the panel with some layers rigid polyiso. Just through bolt it with some carriage bolts. Just make sure you have headroom above the panel to actually get up there.

 

[ddurrett896]

Are you dead set on OSB? Metal is cheaper, lighter and doesn't need to be painted.

 

[CraigStu]

Since you don't plan to use it for storage where you want it cut and install two 2x4s betweent the bottom cords of the trusses. Now you have a box. Cut a piece of whatever sheet you want so it is 2-3 inches longer each way than the box you just made. That gives you 1 to 1.5 inch of overlap where it will sit on top of your 2x4 box. Gravity will keep it there just fine. You could put a pair of hinges on it but then you need a way to keep it open when you crawl up there. I once did hinges, some rope and pulleys to a weight and made mine almost an automatic hold open but I don't think it is worth the effort for your use. You already have a ladder to do this work but do you have a step ladder that will get you to the ceiling? You want it to go as close as possible. The crawl from the ladder to attic is MUCH safer if the top is just a few inches below the ceiling.

 

[billconner]

For other reasons, I'm putting an esterior access panel in gable, fwiw. Unbroken vapor barrier, and appearance a high priority.

 

[Hank11]

There have been probably hundreds of thousands of houses where a bottom chord was cut and a 32" wide box was built for an attic access opening. You need good design and execution, but its just not that hard.

 

[swamplife]

I've hung 7/16 OSB on the ceiling by myself, had but not impossible. As mentioned above, use a drywall lift to make life easier.

I did some 1/2'' drywall sheets myself on a ceiling and messed up my neck for a few weeks. I'm using a lift next time I'm hanging stuff

 

[Norcal]

There have been probably hundreds of thousands of houses where a bottom chord was cut and a 32" wide box was built for an attic access opening. You need good design and execution, but its just not that hard.

If anyone is going to start cutting trusses better get whatever is planned blessed by a engineer.

 

[johnharris]

Since you don't plan to use it for storage where you want it cut and install two 2x4s betweent the bottom cords of the trusses. Now you have a box. Cut a piece of whatever sheet you want so it is 2-3 inches longer each way than the box you just made. That gives you 1 to 1.5 inch of overlap where it will sit on top of your 2x4 box. Gravity will keep it there just fine. You could put a pair of hinges on it but then you need a way to keep it open when you crawl up there. I once did hinges, some rope and pulleys to a weight and made mine almost an automatic hold open but I don't think it is worth the effort for your use. You already have a ladder to do this work but do you have a step ladder that will get you to the ceiling? You want it to go as close as possible. The crawl from the ladder to attic is MUCH safer if the top is just a few inches below the ceiling.

The access panel will be 14.5" x 48". To keep it from sagging I'll use sandwiched 3/4" plywood. It will be sturdy enough to make it longer on each end as you suggested. I'll add 2" foam pads on top of the panel and around the boxed 2x4s.

I got a panel lift over a decade ago at HF for under $100. I've only used a handful of times so it's still in good shape. My walls are 11' high and that's the max reach for the lift.

With a discount I got 32 sheets of OSB for just $13 each. Reason I'm not cutting the OSB to match the bottom chords is I don't feel safe on screwing the outer edges of OSB. Shanked nails would be fine but not screws. To support the OSBs I'm adding 14.5" spacers between bottom chords where the OSB mates. I'll screw into those. Same boards used to space the wall studs.

 

[Norcal]

The access panel will be 14.5" x 48". To keep it from sagging I'll use sandwiched 3/4" plywood. It will be sturdy enough to make it longer on each end as you suggested. I'll add 2" foam pads on top of the panel and around the boxed 2x4s.

I got a panel lift over a decade ago at HF for under $100. I've only used a handful of times so it's still in good shape. My walls are 11' high and that's the max reach for the lift.

With a discount I got 32 sheets of OSB for just $13 each. Reason I'm not cutting the OSB to match the bottom chords is I don't feel safe on screwing the outer edges of OSB. Shanked nails would be fine but not screws. To support the OSBs I'm adding 14.5" spacers between bottom chords where the OSB mates. I'll screw into those. Same boards used to space the wall studs.

Predrill the holes on the edge of the sheets but don't leave them unsupported, it will be a better job there are reasons why things are done they way they are done, attempts at reinventing the wheel don't end well.

 

[mike93lx]

The access panel will be 14.5" x 48". To keep it from sagging I'll use sandwiched 3/4" plywood. It will be sturdy enough to make it longer on each end as you suggested. I'll add 2" foam pads on top of the panel and around the boxed 2x4s.

I got a panel lift over a decade ago at HF for under $100. I've only used a handful of times so it's still in good shape. My walls are 11' high and that's the max reach for the lift.

With a discount I got 32 sheets of OSB for just $13 each. Reason I'm not cutting the OSB to match the bottom chords is I don't feel safe on screwing the outer edges of OSB. Shanked nails would be fine but not screws. To support the OSBs I'm adding 14.5" spacers between bottom chords where the OSB mates. I'll screw into those. Same boards used to space the wall studs.

There is no need to sandwich anything for that small. A single layer of 3/4 is plenty and overkill, at that

 

[TRWham]

Screw some deadwood to the sides of the trusses to catch the OSB.

 

[zc15]

Are you dead set on OSB? Metal is cheaper, lighter and doesn't need to be painted.

Where is metal cheaper? Metal around here is $1.25/sqft, and a sheet of osb is $13

 

[Innovate1]

Where is metal cheaper? Metal around here is $1.25/sqft, and a sheet of osb is $13

There is also the cost of mudding and taping and painting. Unless you do that yourself and consider your time free.

 

[zc15]

There is also the cost of mudding and taping and painting. Unless you do that yourself and consider your time free.

If you're mudding and taping OSB then you're pry going to have a bad time regardless

 

[ddurrett896]

Where is metal cheaper? Metal around here is $1.25/sqft, and a sheet of osb is $13

McElroy metal

 

[johnharris]

The access panel is quite tight but being thin I can easily make it thru that 13.5" opening.

I finished the ceiling 2 weeks ago. I decided to insulate and board up the walls before painting the ceiling. I threw 1 layer of Kilz original oil based primer followed with 2 layers of latex ceiling paint.

I hardwired six 5,000 lumen LED shops lights after painting the ceiling. Also threw in a string pull lamp in the attic so I won't always need to carry a flashlight up there.

I'll start painting the walls this weekend.