house plans

How Roof Trusses work with Pre-Designed House Plans

Have you ever wondered how the various components of a new home are made? Roof trusses are particularly important because of the loads that they’re expected to bear. Let's walk through the truss design and manufacturing process to better understand the engineering that goes into a completed home.

How Trusses work with Pre-Designed House Plans

House plans that include a trussed roof generally involve too many location specific variables for designers to be able to provide the truss design that will be required. The geographical location of your proposed home plays a critical part in the truss design. Wind, seismic and snow loads all need to be taken into account and those loads carried through the supporting structure.

Work with your Truss Company

The truss manufacturer will gather information from you, such as site location, and your roof finish materials. They will use that information to decide what design criteria to us in the design of your roof truss system. Live loads include snow or movable things within the structure (attic storage), while dead load is the weight of the building materials that the home is made from (ceiling material, roof finish materials, framing, and insulation etc).

The Engineering Process

With the layout information provided from your house plans, along with the site specific design criteria mentioned earlier, the manufacturer engineers roof trusses that can support both live and dead loads involved. The truss manufacturer will use the plans and designed load bearing points as a guide, but ultimately the manufacturer’s design will determine where there will need to be supporting structure beneath the roof. This information should be compared to the house plan structural design prior to construction.

Finalizing your Construction Documents

Once the truss design is complete, the loads determined from truss analysis should be compared to the supporting structure in your house plans, and the structure should be adjusted as required. With Mascord house plans, structure is initially determined using truss loads from "best guess" wind and seismic values, to create a structural design that works in most cases. Many other house plan publishers do not include structural details at all, and leave you to have all the beams and posts calculated for the entire home.

It’s important to remember that the structural analysis of a home starts with loads at the roof, and each load needs to be carried through the home to the foundation, which then needs designing to support those loads. You can't ignore a changed truss design.

To help in this matter, we offer our clients a free truss review, where our designers will compare your specific truss design to the house plans structure, and recommend changes where warranted.

For more information, contact a reputable truss manufacturer in your area.