Attic steps, 30" wide. How to install

[Coach529]

Still in the design stage of my garage, but I would like to add 30" wide attic steps to my garage.

How do your install 30" wide attic steps on rafters placed 24" OC?

 

[KEH]

If you are in the design stage, why not just design one rafter to have 30 inch wide spacing? If that leave the ceiling or attic floor insufficiently supported, run another rafter in the remaining space and frame around the opening to support the rest of the rafter, using steel supports if necessary. Remember you need head space where the stairs come out in the attic.

KEH

 

[Coach529]

If you are in the design stage, why not just design one rafter to have 30 inch wide spacing? If that leave the ceiling or attic floor insufficiently supported, run another rafter in the remaining space and frame around the opening to support the rest of the rafter, using steel supports if necessary. Remember you need head space where the stairs come out in the attic.

KEH

I am in the planning stages. I was just curious what the right way is. Two options the way I see it, either space rafter further apart or cut the bottom cord and frame around.

Which option is better?

I am using 8/12 pitch bonus room rafters so head room will not be a problem.

 

[tomroblee]

My 36' x 64' footprint country home was built with attic trusses spaced 24" on center. Where I had the stairway, they just left out one truss to create a 48" wide opening and doubled the trusses on both sides of the opening.

 

[Coach529]

My 36' x 64' footprint country home was built with attic trusses spaced 24" on center. Where I had the stairway, they just left out one truss to create a 48" wide opening and doubled the trusses on both sides of the opening.

I assume they spanned the 48" between trusses on the top cord with 2" x 4" or 2 " x 6" to support the roofing?

 

[pattenp]

You don't cut trusses. You space as needed for the stairs and double the truss on each side as tomrolee said. At the roof you inslall purlins between the truss to fill in the wider space for the roof decking.

 

[tomroblee]

I don't really recall how they blocked the space between the trusses. The house was being built about 100 miles away from my primary residence, and I don't have any pictures that shows the blocking.

I believe that they may have put blocking between the two trusses at the top, then installed a regular rafter between the two trusses?

I Googled "attic truss stairway" and found an image of one approach.



I also have one picture of my own house showing the attic trusses. They were 12/12 pitch spanning 36' ,so had to be made in two pieces.