[jimmyfloyd]

Ok, I am looking to add a little bit of light storage space for my pool floats and plastic lawn chairs, and I would like to use the attic space in my garage. The problem is that my 24'x24' 2 car garage only has 3 joists in it, spaced about 5-7 feet apart. See the pictures. They are all solid pieces of lumber from one side to the other, and are 2x 8 or 10 I believe. There are some central braces going up to the ceiling, but not a lot. There are also 2 2x4 cross braces going perpendicular to these that are made up of a couple overlapped.

So what can I do to strengthen these up so I can put stuff up there?

http://s282.beta.photobucket.com/us...cts/100_2282_zpse7e53916.jpg.html?sort=3&o=31

http://s282.beta.photobucket.com/us...cts/100_2283_zpsfb31f2de.jpg.html?sort=3&o=30

 

[CanAmGuy]

Those 2x8's are collar ties, they are there to prevent your rafters from spreading (and your walls from bowing out) due to roof load. They aren't designed to have any load applied on top of them. It's not to say you couldn't do something different up there to give you storage area. The important part is that you don't add any load to the underside of your rafters. Last thing you want to do is compromise your roof.

 

[joecaption]

http://bct.eco.umass.edu/publications/by-title/understanding-loads-and-using-span-tables/

 

[GBrackins]

did you go to UMass-Amherst Joe? nice building construction program

actually they appear to be rafter ties (a ceiling joist is a type of rafter tie) as they are located within the lower 1/3 of the attic space (top plate to ridge) and as CamAm said they resist rafter thrust which can cause the tops of walls to be pushed out. Collar ties are typically located in the upper 1/3 of the attic space and keep rafters from pulling away from the ridge board.

you'd have to figure out what your loads would be and then use span tables for ceiling joists based upon those loads. Check out this link that will provide you with ceiling joist spans based upon loads and species of wood used. These tables are found in the 2009 International Residential Code which is the basis for many building codes.

Good luck!

 

[hammerlane]

Those 2x8's are collar ties, they are there to prevent your rafters from spreading (and your walls from bowing out) due to roof load.

Those are rafter ties. Collar ties are placed on the upper 1/3 of opposing rafters