Repair Roof Truss Uplift
Repairing Truss Uplift Problems
If you're building a new house, inspect your trusses. They should not be nailed to a wall using 16 penny nails. If you see nails, they must be pulled and the special truss clips installed in their place. The walls need to be attached to the trusses so that they do not fall over.
When you need to repair trusses in your home, be prepared to be in a very grumpy mood. I just wanted to warn you. You will want to kill the rough carpenters who framed your house. The job is miserable, especially if you try to tackle it in the summer.
Existing House Problems
There are hundreds of thousands of existing houses that suffer from truss uplift. I saw it firsthand, for the first time, six years ago. I did not realize at the time what exactly was happening. I did determine by questioning the homeowner that it was a seasonal problem with cracks being the worst in February.
To achieve the best results, the job must actually occur in two phases. You need to release the trusses from the walls and reattach them with clips in the dead of winter. Then the summer months will find you installing the drywall clips or wood blocks that will hold the ceiling drywall tight to the wall drywall.
In the dead of winter the trusses should be bowed upwards. There should be a small gap between the truss and the top wall plate. If you are lucky, the gap will be large enough to easily slide a hacksaw blade between the pieces of wood. Cut through the nails holding the truss to the wallplate. Be on the lookout on both sides of the truss for electrical wires! An easier method may be to pull out the nails using a special tool called a cat's paw.
Once separated, the trusses need to be reattached to the walls with the special L-brackets. When attaching the truss clips, be sure that you drive the nail through the center of the slot on the leg that points upwards. Don't nail too close to the bottom or top of the slot. In addition, the drywall that is attached to the trusses near the walls needs to be released from the corners where walls meet the ceilings. You can do this by installing the 2x6 blocks in the summer months when the ceiling has settled back into position.
You can now safely install the drywall clips and retention blocks between the trusses. If you try to do all this work in the winter, you may crack the drywall as you beat it down to the top of the walls.
The following winter, nail pops will appear at each interior wall where a truss passes overhead. The nails need to be countersunk into the trusses to complete the job. Use a large, flat nail set to drive the nails up through the drywall into the truss.
If you do not do this, the patching compound you use to deal with the fresh nail pops will be pushed from each nail pop the following summer. As always, the time required to solve a problem far exceeds the time to do the job right in the first place. Fortunately, in this case, the work required is not too difficult. It simply is spread out over a period of months. Be careful working in the attic. Don't fall through to a room below!
If you are a gambling person, you can try to do all of this in the winter months in two weekends. Test an area of the ceiling first to make sure you are not cracking the drywall. If you can do the entire job in one phase, consider yourself lucky.