Proposed Two-Story Residence

Project Details

This project involves the comprehensive structural design and engineering for a new two-story residential structure and attached garage. The structural assembly utilizes a sophisticated hybrid framing system, incorporating standard Douglas Fir (DF) lumber for rafters and joists, engineered wood products such as Parallam PSL beams and TJI joists, and structural steel components includng W-shape floor beams (W12x53, W12x40,W16x36) and SHS steel columns. The design process included a rigorous analysis of gravity and lateral loads in accordance with the 2018 International Building Code (IBC), ASCE 7-16, and the 2019 California Building and Residential Codes (CBC/CRC). Given the project’s location, the structure was engineered to meet high seismic demands characterized by Seismic Design Category E, with mapped short-period spectral accelerations (Ss) of 2.380g and a site-specific design acceleration (SDS) of 1.904g. The lateral force-resisting system (SFRS) consists of strategically placed timber shear walls and pre-manufactured Hardy Frame (HFX) panels to ensure stability against calculated seismic base shears of over 40 kips. Environmental loading analysis also accounted for basic wind speeds of 91 MPH under Exposure B conditions. The foundation system features a network of independent reinforced concrete pad footings and continuous wall footings. These elements were designed to perform reliably under a specified allowable soil bearing capacity of 1,800 psf (1.8 ksf) based on a Site Class D soil profile.

Role

Structural Engineer/Designer

Services Provided

The scope of services included the preparation of structural analysis, design calculations, and structural plans for the proposed structure. Structural calculations considered loading analyses for wind, seismic, dead, and live loads, together with the structural analysis and design of all structural components, including foundations, columns, beams, shear walls, rafters/trusses, and other required structural elements to ensure adequate strength, stability, and code-compliant load transfer. The services also included the preparation of structural drawings consisting of foundation plans, floor framing plans, roof framing plans, shear wall layout plans, and structural details, notes, and specifications required to clearly communicate the structural design intent and construction requirements.