I beam ceiling joist

[Charley L. Bottger]

This is the ceiling above an oversized garage with the I-beams as ceiling joist. There are 4 braces from the roof rafters that are being supported on the decking above the garage what say you framing carpenters

[Bruce A. King]

The braces may be too long for 2x4's
They need to be nailed into the top of an I-joist not just the OSB.
A strongback or hog needs to be horizontal across the rafters where the 2x4's are supporting.
Collar ties are likely needed also for this size area.

[Charley L. Bottger]

Originally Posted by bking

The braces may be too long for 2x4's
They need to be nailed into the top of an I-joist not just the OSB.
A strongback or hog needs to be horizontal across the rafters where the 2x4's are supporting.
Collar ties are likely needed also for this size area.

I would say poorly constructed my main concern about these braces were will the I beams across this garage ceiling support the weight of the roof rafters normally I see these kinds of braces only on a load bearing wall not back to an non-supported ceiling. These types of I-beams are just now becoming popular in this area. I need to get up-to-date on their load capacity.

[Bruce A. King]

There are different strength I-joists.

If the top and bottom flange look like LVL lumber they are for higher loads.
Most have the regular sawn lumber flanges.

It also depends on how much roof area is being supported.
Its a judgement call for me, if it looks bad I write it up.

I would think that the roof over most garages can be supported just fine on those I-joists.

[Charley L. Bottger]

Originally Posted by bking

There are different strength I-joists.

If the top and bottom flange look like LVL lumber they are for higher loads.
Most have the regular sawn lumber flanges.

It also depends on how much roof area is being supported.
Its a judgement call for me, if it looks bad I write it up.

I would think that the roof over most garages can be supported just fine on those I-joists.

Bruce;
I did not write it up as a repair but did mention in the narrative that the braces in this manner would not be exceptable in conventional framing stick built Thanks

[Bruce A. King]

Many times around here, they will use one size larger ceiling joist and brace the roof off the ceiling joists. They use a right angle horizontal brace across the ceiling joists also. It really all comes down to spans and lumber sizes.

[Charley L. Bottger]

Originally Posted by bking

Many times around here, they will use one size larger ceiling joist and brace the roof off the ceiling joists. They use a right angle horizontal brace across the ceiling joists also. It really all comes down to spans and lumber sizes.

Ouch that type of framing is not used here.

I most usely see roof rafters on the smaller homes 1500 to 2000 square ft. that have just a basic purlin running along the roof rafters that are supported back to a load bearing wall on approximately 45 degrees not the ceiling joist and if there is no load bearing wall within reach they leave the brace off and this is always visible from the street when I first drive up to the property as there will be dips visible in the ridge line. not good. A lot of these homes have a foot print in the form of a T-bone with valleys on each leg of the T These T's have roof supports back to a load bearing wall roughly on a 22 degree. What I find in a large sections of homes the builder will skimp on his lumber demision. Say the valley's and the roof rafters are constructed of 2X6's and the support braces will be 2X4's. IRC states that all lumber shall be supported by the same demision lumber or larger. Or did I read this wrong.