This house was built in 77 by a quality builder. I have questions about the garage which is part of the house. The ceiling joist are only toe-nailed to the top plate and there are 2 2x6 nailed across the top of them.They are not nailed to the knee walls or the rafters. There are 3 joist that have twisted and 1 brace for ridge beam has bowed also. There is another section of the home where the joist are only nailed to the top plate as well. The home does have brick walls up to the joists then plywood. The home also has plywood collar ties. Is this proper?
Phil,
There’s a support wall below this bearing area…right?
You can always recommend a 2x be secured atop of those toe-nailed joists to prevent further twisting.
Agree.
The ceiling joists don’t appear to be structural, and only serve to attach the ceiling drywall to. Had the joists not twisted, you probably wouldn’t have given them a second glance.
Easy fix.
Even back then, solid blocking would have been appropriate to keep them from twisting, but now the only thing that can happen is the twisting might pull the drywall screws through the drywall underneath. 2x4 on top as mentioned, will help any future rotation of the members.
I am just surprised, built in 77 that the attic is as clean and void of storage as it is.
The temporary king post installed must have had some compression when installed and over the years is relaxing it’s wood fibers by bending the way it is. Nothing to be concerned about.
I would have recommended a little more insulation to meet todays energy codes. :)
Thanks for the help!
Regardless of their purpose, all ceiling joists are “structural”.
Rule #1 of HI: Don’t design the repair. Just describe the condition (i.e., twisted ceiling joists) and refer it to a licensed contractor.
Joe F, ceiling joists are part of the structure but aren’t structural. You can’t, (shouldn’t) brace off of them. You can brace the roof off of exterior walls, interior walls and beams, not Ceiling joists. As Jeff J said these joists aren’t structural. They are only doing their job of holding up the sheetrock ceiling, nothing else. There is alot that could have been done with this ceiling joist system to make it better, but it is not structural as most ceiling joist systems are not. IMHO
Joe K., please define the word “structural” explicitly. Saying ceiling joists are “part of the structure but aren’t structural” sounds a little funny, don’t you think?
Here’s one I found: "affecting or involved in structure or construction; “the structural details of a house such as beams and joists and rafters; not ornamental elements.”
Hey Joe, shouldn’t you be sleeping?? 
I almost was.
Good point- “the structural details of a house such as beams and joists and rafters; not ornamental elements.” But your qoute says Joists, not ceiling joists. Of course Floor joists (not ceiling joists) are a major structural component of a home or any structure. My point is that ceiling joists, just as interior non load bearing walls are part of the structure but not load bearing(non structural). 
The brick veneer on your home is part of the structure, but the brick is non structural, it’s not supporting anything.
Phil, what do you have 1/2 " ply on them? The collar ties are required to be at least one inch thick. 4’’ wide. Also the purlin in the picture is required to be the same size as the rafter. So 2x6 purlin to match 2x6 rafter (the braces can be 2x4), looks like 2x4 purlin in the pic. What also stands out is that there is a purlin and the bracing only on the left side of ridge. the span on the right side looks the same. Also the purlin does not extend over the garage area. Maybe they figured out after putting up one section that the rafters weren’t overspanned ?? Also as Marcel mentioned the insulation appears inadaquate for todays standards. Looks like about an R-19 batt insulation. You don’t say what area you are in. In my parts we don’t do anything less than a R-30 blown. But having been built in ‘77 the purlin size, collar tie thickness and insulation thickness on this home may have been acceptable. Marcel, my guess would have been that ridge brace was bowed from the start by being forced into position. What do you think? Either way, not an issue. Since the joists over the garage are running the opposite direction of the rafters , rafter ties should have been installed over them a minimum of every 4’ extending to and fastened to the rafters. These could have been fastened to the top of the joists to help prevent the twisting. These joists should have also been connected better at the ends. On one side they could have butted and fastened into that last joist over the wall coming from the living area and on the other end should have tied into the 2x4 wall. Phil, with the twisting shown in your pics was there not evidence in the sheetrock of the fasteners popping loose?
Covered it pretty well Joe.
If I go back to framing practices of 1977 in Northern Maine, the ceiling joist of the garage would have been nailed to the last ceiling joist of the dwelling unit as you said. That would have prevented the rotation and at the exterior wall, they would have been nailed to a box header which in turn could have been used to nail the studs of the gable end.
In the picture, it looks like the struts are located where the splice joint of the ceiling joist are, but where the purlin is close to the ridge like so, don’t amount to a hell of beans. The other side, can’t tell where the splice is or if it is full span.
We used to just chase the bearing walls with knee walls instead to distribute some of the load on the the walls from the rafters. That was only done when the rafter span was 16’ or more.
Stick built framing as such, we used 5/8" plywood gusset plates on the ridge if they were hand built trusses, other than that when a ridge board was used, 2x4’s were used for collar ties. Most people wanted a walk-through attic for storage so the collar ties if used were always held high.
Finally, that 2x4 under the ridge, it is possible it was bowed like that when they slapped it in.
Cheers. :)
I bielieve that’s 3/4" thick, since it’s OK to use 1x6.
That’s modern code, but there have been many thousands of homes built with 2x6 purlin strongbacks with no sign of failure. At the time this home was built, same-size strongback was not a requirement.
It looks to me like they had no wall to brace down to on the right side and that’s why there’s no purlin. There is a catwalk and a partial strongback so I’m guessing the ceiling joists on that side are overspanned.
Agreed.