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Anderson Anderson Architecture
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The objective of this project is to produce a low-cost, high-quality, manufactured building system that is easily adaptable to specific sites and programs.

All material and structural systems are selected from relatively common, non-proprietary systems with multiple manufacturers so that built-in competition encourages low costs and long-term availability of components. Coordinating and combining existing manufactured systems distributes capital investment in system detailing, inventory and prototyping among a group of sophisticated manufacturers with already established, project-specific customization and component packaging and delivery systems. By creatively combining a small number of manufactured systems into one comprehensive system approach, there is no need to begin a costly design of an entirely new system, and there is the certainty of long-term applicability and wide-spread industry support.

Design process

The current system and prototypes are part of the architects' long-term series of prototype buildings that experiment with the creative coordination of existing, standardized systems into comprehensive approaches to low-cost, highly adaptable structures. In association with various manufacturers, the architects have designed and built a number of prototypes as a design/build/research cycle.

The design process involves drawing, model and mock-up building, design and engineering collaboration with contractors, and the full-scale realization of prototype structures built for individual clients or developers.


The building is designed to be highly adaptable to varying site conditions. The modular steel frame structure can span between supporting columns or foundation walls located below truss bay connections, and can cantilever up to 32' at the ends of the building. 

This flexibility is intended to allow the structure to adapt easily to a variety of complex site conditions, minimizing the requirement to disrupt the natural topography and vegetation, and reducing the amount of expensive on-site foundation work. Hillside sites and sites with unusual soils often require especially expensive excavations and foundation systems. The cantilever truss structure is particularly well suited to these sites as it requires a minimal number and area of foundation points, preserving the landscape and while greatly reducing site development and foundation costs.

Vierendeel truss structure

In addition to providing great flexibility for placement and configuration of the foundations, the two-way Vierendeel truss creates a complete, self-contained structural system independent of the building enclosure and interior walls. All gravity and sheer forces are resisted solely by the moment-frame truss structure, and no shear walls are required, providing great flexibility in the window placement and in the positioning and later modification of interior walls.

Foam and oriented strand board structural insulated sandwich panel system (sips)

The secondary structural system and primary insulated enclosure system utilizes manufactured sandwich panels composed of expanded polystyrene foam glued between skins of OSB (oriented-strand board). These panels have great structural rigidity in spanning between steel supports as roof, floor and wall systems, and can cantilever beyond the frame support points to allow different building widths without modifying the pre-engineered structural frame. The panels provide high levels of insulation, are relatively inexpensive, can utilize primarily recycled content, and are relatively free of unhealthy gas emissions. Each 4' wide panel is shipped to the site cut to the full width of the floor or roof, or to the full height of the walls, to reduce the handling of small parts and speed the on-site erection process. As a manufactured system, installation drawings, engineering, detailing, custom pre-fabrication and site delivery are all provided by the manufacturer, allowing for great flexibility in design, ease of construction and low cost compared to more conventional systems of structure and enclosure. Using the same system for roof, walls and floor provides for a great simplification of the materials ordering and construction process, giving economies of scale for even small buildings.

Window wall enclosure

The enclosure system is designed to allow a range of window or curtain wall systems by various manufacturers. The current prototypes use an insulated aluminum storefront door and window system by Traco Manufacturing.

Vegetated membrane roof

The waterproof roof membrane is a one-piece, prefabricated pan rolled out and clipped into place in less than one day. The building assembly process allows the roof membrane to be installed early in the construction process, before wall and floor assembly, greatly reducing labor costs and unpredictable weather-related costs and delays. In the case of the two current prototypes and in many other urban and natural hillside locations, the roofscape is an important visual element, both as seen from the building itself and as a part of the larger built or natural environment. The roof is designed to have a sod roof covering, or can accommodate roof top terrace living space surfaced with a variety of materials.


The modular system is designed to accommodate a range of plug-in accessory items such as exterior decks and stairs, window boxes, sunscreens, daylighting shelves, and solar water heating or electrical generation panels. The intention is to have a basic building structure that allows for extensive customization over time, attaching accessory elements from many manufacturers without the need for custom attachment systems or costly modifications to the primary structure.

Construction process

The major structural and enclosure elements are all panelized systems, pre-fabricated off-site. This approach minimizes unpredictable site labor costs, speeds construction, and minimizes disturbance to the existing site context. The minimal foundation requirements also speed construction, reduce labor costs and reduce site disturbance. The construction period of foundation through exterior enclosure is expected to be less than one month, with an additional 6-8 weeks required for installing building systems, fittings and finishes. No interior elements are essential to the structural integrity of the building, so the interior can be constructed by owners or less skilled labor without structurally dictated quality or scheduling requirements.

Mass customization

Because the system components are adapted from readily available, multiple-manufacturer products, the buildings can tap into the economies of large scale that result from the research and production capacities of large manufacturers. The small number of relatively simple raw materials used in the products mean that the manufacturers are in turn purchasing in large quantities from competitive sources. The customization for specific sites and programs is a result of the specific configuration of pre-designed modular components within a system of typical assemblies designed by the architects in collaboration with the manufacturers.

Quality of life

Although the materials and methods of construction are chosen for efficiency and affordability, the underlying design principles guiding the development of the system have the larger goals of producing affordable, high quality buildings that offer variety, adaptability, convertibility, strength, simplicity, spatial richness, and optimized access to views and light.


Types of steel used in building
Living area   220 m2
New-build home       ✓
Location of steel solutions
External wall    
Light steel sections    
Types of steel used in the building
Long carbon steel