Category: Residential
Location: Emeryville, CA
Size: 2469 sq. ft.
Masonry Used: Approximately 1232 blocks (or 973 sf or 93 linear ft) of Omniblock concrete masonry units (8x8x16).
Submitted by: Swatt | Miers Architects

Project Description

In developing a new approach to prefabricated housing, the design team embraced a hybrid design that blends substantial site-built masonry elements with factory-built modular components. The goal of using block as a key component of this system was not only to save time and money, but also to create a signature design element for the housing brand. To accomplish these goals, concrete masonry units (CMUs) were utilized for the garage walls, first floor hallway, and living room walls. The block is left completely exposed on the interior and exterior-with only the necessary sealants-to acknowledge the “honesty” of the materials and structure.

With today's structural and energy codes (especially in California, where the bar for both is set quite high), designing a home with exposed CMU presented some challenges. Fortunately, we were able to work with an innovative product called OmniBlock. The Omniblocks have the same exterior dimensions and aesthetic as traditional block (8”x8”x16”); however the internal structure is designed with two channels that accept custom foam inserts. These blocks were able to increase the insulating R-Value over that of a traditional CMU, while also providing internal grouting/rebar for structural reinforcement.

There were tremendous time and cost benefits with these masonry elements. In the context of our prefab system, the block walls are erected on-site concurrently with the fabrication of the modular elements at the factory. The exposed blocks, not requiring additional finish materials, provided a significant cost benefit over other more involved interior and exterior finishes.

The masonry elements contributed to the overall design concepts. The exposed CMU adds an “anchoring” design element to the architecture, making a stronger visual connection to the site than just prefab alone. The design of the straight-stacked block reinforces the crisp, modern lines of home. The CMU walls are prominently showcased at the entry; beginning at the exterior entry bridge the CMU passes through the doorway into the entry hall, blurring the line between inside and outside.

The sustainability and durability benefits of masonry units are also significant. This home is designed to be net-zero energy with many other sustainable features- including hydronic radiant floor heating, rain-water catchment, living green roofs, and photovoltaic panels. Not only is CMU block a low-embodied energy material, but also adds to the thermal comfort of the building. As incorporated into the passive-solar design of the home, the block provides thermal mass to store heat energy that is drawn into the home through the large walls of glazing on the south façade. The benefit of this design is lower demand on the mechanical heating systems.

By utilizing concrete masonry units as a signature element in our architecture we are not only meeting our design and sustainability goals, but also improving our bottom line.

Project Participants

Architect / Designer's Name: Robert Swatt
Company: Swatt | Miers Architects
Phone: (510) 985-9779

Structural Engineer' s Name: Shane Lothhrop
Company: Innovative Structural Engineering
Phone: (951) 600-0032

General Contractor's Name: Kathleen Liston
Company: Eco Offsite
Phone: (888) 491-0333

Masonry Contractor
Company: Terra-Con, Inc
Phone: (925) 218-4720

Masonry Supplier's Name: Denny Miller
Company: Omniblock
Phone: (877) 711-6664

Landscape Architect's Name: Joseph Huettl
Company: Huettl Landscape Architecture
Phone: (925) 937-6400

Company: Monterey Energy Group (T24 Consultant)
Phone: (831) 372-8328