Live residential design: Taos, NM custom home (Pt. 1)

What this webinar covers

This session focuses on taking information directly from structural drawings of a custom home in Taos, New Mexico and entering it into Calcs.com to design real members. Connor Conzelman, Director of Customer Success, walks through two examples: a deck joist and deck beam system using the Wood Beam (ASD) preset with load linking, and a steel floor girder using the Steel Beam (LRFD) calculator. A brief look at the Wood Connectors calculator for Simpson strong-tie hanger selection is also included.

The session does not cover lateral loads. Connor explicitly noted that wind and seismic examples were outside the scope of this session, and committed to creating separate help content covering those topics.

Reading bearing lengths from drawings

Determining bearing length requires tracing from the framing plan to the relevant detail sheet. For the deck joist in the example, Connor went to detail sheet S3.3, detail 7 to see how the joist connects to the deck beam. The detail showed a rim joist occupying width at the support, so the actual bearing was the nominal beam width minus the rim joist thickness.

The deck beam in the example was a 10x18 (actual width 9.25 inches). With one rim joist at 1.5 inches, the bearing length at the top support worked out to 7.75 inches. At the bottom support, rather than bearing directly on another member, the joist was assumed to sit in a Simpson strong-tie hanger. Connor looked up the hanger seat width inside Calcs.com's Wood Connectors calculator by selecting the connector type for a 2x10 joist, which displayed a width of 1.75 inches.

Connor acknowledged that in practice many engineers use a conservative estimate for bearing when they know it will not govern, rather than tracing through the detail. The walkthrough was included for completeness.

Setting up load linking from joist to beam

One of the main features demonstrated is load linking. After designing the deck joist (J2) as a 2x10 Doug Fir-Larch, the calculation is linked as a line load onto the deck beam. In Calcs.com, a dropdown shows all linkable joist calculations in the project. Connor selected the deck joist, set the start location to 0, and specified that the load runs the full length of the beam (0 to L) because the joists ran the entire span.

The practical consequence Connor highlighted is that any change to the joist calculation - for example adjusting the center-to-center spacing from 16 to 18 inches - automatically recalculates the deck beam, because the pounds-per-linear-foot delivered to the beam updates. This avoids the need to manually transfer loads between separate spreadsheets or documents.

Connor also showed a second type of load linking: connecting the deck joist calculation to the Wood Connectors calculator to design the Simpson strong-tie hanger. The connector calculator takes the reaction from the linked joist and shows pass/fail status for hanger options.

Steel girder example: inputs from drawings

The steel girder in the example spans 28 feet and is simply supported. Connor used LRFD for the steel design, noting that while ASD is also available and the interface is the same, most users he sees choose LRFD for steel.

For lateral bracing, Calcs.com defaults to no continuous bracing to be conservative. Connor changed this to top bracing because a floor girder in this configuration would have the floor sheathing providing lateral restraint at the top flange.

Tributary width was determined from the drawings by measuring to the next support or wall on each side. The girder had 20 feet to one side and 8 feet to the other, giving half-distances of 10 and 4 feet for a total tributary width of 14 feet. Connor flagged that Calcs.com does not model the torsional effect of asymmetric tributary loading, consistent with how similar software handles this for residential and light commercial applications. The full 14-foot tributary width is entered as a single value.

Applied loads for the steel girder were floor dead load of 20 psf and floor live load of 40 psf at full beam length. The specified section from the drawings was a W12x45, which checked out at 82% on the critical deflection check. Connor showed how the member selector can be filtered by maximum width and depth to find passing sections if the specified member had not already been known.

Code versions and support settings

Connor covered several practical settings that come up when starting a project. In Project Defaults, the Design Code for Load Combinations dropdown allows selection from IBC 2021 back to IBC 2009, IRC, California Building Code 2022, and Florida Building Code 2020. He noted that IBC 2021 support was recently completed, that all concrete calculators were updated to ACI 318-19 (which also brought CBC 2022 up to date), and that the Florida Building Code 2020 had been added within the prior few days.

For support types, Calcs.com defaults all supports to Pinned. Connor confirmed that Fixed, Roller, Hinge, and Brace options are available from the support type dropdown when a different condition applies.

On the question of whether LRFD and ASD calculations can be linked, Connor tested this live: an LRFD wood beam calculation cannot be linked into the ASD Wood Connections calculator. He recommended keeping the design method consistent across all linked calculations in a project.