Today on the Total House Construction Series – Foundation to Finish I’d like to talk about preparing a house for truss delivery and erection. Preparing the house frame prior the truss delivery can make the erection process quicker and safer.
Typically pre-engineered trusses come with a set of engineering plans. The plans contain information about each type of truss, the truss plan layout and truss bracing details. The truss plan layout will identify the truss spacing and any special bearing plates or connectors.
For this new home there are about 20 different truss types. That may sound like a big number but there are common trusses, cathedral ceiling trusses, trayed ceiling trusses and gable trusses for each size. Most of the trusses bear directly on the wall top plate and get secured with truss hurricane clips (see the shiny galvanized connectors in the photo).
For special truss loads, such as required by a girder truss (multiple trusses fastened together for extra strength, typically to support other trusses similar to a beam) there may be a special connector or bearing plate required. For this house there is a very large bearing/connector plate required to support a girder truss. Quite often if a house uses attic trusses the the engineer may specify a stronger wall top plate (such as southern yellow pine, or Douglas fir).
So a day or two before we receive a truss shipment we will lay out all of the trusses on top of the wall and attach the hurricane clips. This is a huge time saver on the day the trusses are delivered and erected. This approach also improves the overall safety of truss erection by eliminated confusion and allowing the carpenters to focus on what they are doing. We like to use a pair of pliers to slightly “open” up the hurricane clip to make it easier to drop the truss into place with the crane.
Please be sure to come back and read about the truss erection next week. I’ll cover basic safety guidelines for truss erection. This is extremely important as hundred of workers are hurt each year when trusses collapse during erection due to poor bracing and careless practices. If you enjoy this site I encourage you to simply sign up for my feed via RSS or an email subscription, it’s easy to do with the following two links.