Truss Repairs Made Simple: What Happens and How to Handle It

Repairs aren’t the most glamorous part of working with trusses, but the reality is, they do come up. And when they do, they’re usually straightforward to fix. In this post, I’ll walk you through what kinds of truss repairs you might run into, what causes them, and how to handle them without losing sleep or your warranty.

This is meant to give you a general understanding of common repairs, but it’s not a substitute for an engineer’s stamp. Always talk to your truss manufacturer and the engineer who designed your trusses before doing anything.

Manufacturing Defects: What Happens in the Plant

The most common manufacturing defects are missing plates and damaged or broken members.

A missing plate happens when the metal connector that holds parts of the truss together wasn’t installed properly. It's possible that it didn’t stick fully during manufacturing, got torn off during shipping, or it just got missed. Regardless of the reason, the fix is usually a gusset made of plywood or OSB. The gusset is cut to fit and nailed or bolted into place, following the engineer’s exact instructions. That restores the truss to its full strength and keeps the warranty intact.

You may also encounter a broken member. That could be caused by something like a knot in the wood or damage during loading. In this case, the engineer typically calls for a scab repair. You place a new piece of lumber on both sides of the break and fasten it as instructed. This brings the truss back to its original strength.

If a whole member is missing, meaning there's just a gap where a piece of wood should be, the engineer can still design a fix. It may involve cutting out damaged ends, connecting a new joint with a gusset, and installing a new member in place. These repairs are all common, simple, and well within reach when done the right way.

The best thing to do if you notice a defect is to call your truss manufacturer. They’ll get in touch with the engineer and make sure you get a fix that’s both safe and covered.

Design Defects: When Trusses Don’t Fit the Structure

Design defects happen when the trusses as built don’t match the structure on site. Maybe the ceiling came out flat when you expected a vault. Maybe a truss is too long, too short, or too tall. These issues show up in the field, but they’re solvable.

If you expected a vault and got a flat ceiling, that doesn’t mean you have to start over. The engineer can come up with a modification that allows you to create the vault with the trusses you already have. That could mean cutting a section of the truss and adding new members with gussets or scabs. It’s a clean fix that keeps your project moving forward.

If a truss is too long, that’s often because something changed on site, like a wall not being where the designer expected. The extra length can be trimmed, and gussets can be added to restore structure. Your truss manufacturer and engineer will walk you through the process.

When a truss is too tall, it might be that the pitch or heel height wasn’t calculated correctly. In that case, you can usually trim the top down and sister new members to the face to keep everything structurally sound.

A truss that’s too short is one of the easier fixes. Let’s say you’re tying into an existing roof and the pitch is just a bit off. The engineer might tell you to add a new piece of lumber to the top chord or even attach a new member alongside it. Another option is padding the top chord with a ripped piece of material to match the intended pitch. Both options restore the alignment and strength.

Many of these issues can be avoided with good communication. Our video on verifying site measurements shows exactly how to gather accurate data before trusses are even ordered. It also comes with a fillable sheet to help with consistency across projects.

Simple Fixes. Solid Outcomes.

Most of the time, trusses go up with no problem. But when something does need fixing, it doesn’t have to derail your build. With the help of your truss manufacturer and engineer, repairs are manageable, maintain full structural integrity, and keep your warranty intact. When repairs are done correctly, you can move forward knowing your building is just as sound as it would’ve been if the issue never happened.

If you’ve got questions or need help navigating a specific issue, reach out. That’s what we’re here for.