California’s office tower (W)rapper is named after its wrapping steel exoskeleton, which provides support to the 16-story building. The building is not significant just for its appearance, but also for its sustainability features.
The structural concept of (W)rapper, built in a former industrial and manufacturing zone in Central Los Angeles and Culver City, originated in 1998 and was initially showcased by the project’s architect, Eric Owen Moss Architects (EOMA) in an exhibition at the Wexner Center in Columbus, Ohio. Unlike conventional high-rise buildings that rely on columns organized along modular grid lines, the tower utilizes a network of curvilinear bands emanating from multiple geometric center points to provide support. Each curving band wraps around the predominantly rectangular building envelope and folds around every vertical and horizontal corner until it reaches the ground.
To ensure seismic safety, the bands are supported by a base isolated foundation that separates the tower structure above from the isolator foundations below. This design allows the building to respond and move safely during seismic events. In terms of sustainability, the base-isolated structure significantly enhances the building’s resilience, making it five times more resistant to earthquakes compared to a typical American high-rise. In the event of a major earthquake, (W)rapper would remain standing and ready for occupancy the following day.
The structural lifecycle of (W)rapper is a key measure of its sustainability, greatly reducing its carbon footprint throughout its usable lifespan. Compared to more conventional structural concepts, (W)rapper provides both the city and its tenants with the highest possible seismic safety rating in the U.S., making it the only high-rise commercial office building in the country that utilizes such a base isolated structure.
The steel bands of (W)rapper are coated with cementitious fireproofing, and the building core is adorned with a two-coat cement plaster finish. Concrete is not used in the structural or fireproofing concept of (W)rapper. By positioning the bands on the building perimeter, an open and column-free floor plan is created, offering maximum flexibility for interior planning. The elevator and utility core of the building are offset to the south, freeing up the office interiors and providing further floor plan flexibility.
The seventeen office floors in (W)rapper offer three different options for floor-to-floor heights, which are approximately 4.27 m (14 ft), 5.18 m (17 ft), and 7.32 m (24 ft). In addition, a mezzanine is suspended from the ceiling above the 7.32-m (24-ft) floor, providing tenants with a wide range of use and spatial experience possibilities. The minimal impediments caused by the perimeter bands offer unobstructed vistas of the entire Los Angeles basin from every floor.
Situated along the Expo Line light rail, which connects West Los Angeles to downtown, the (W)rapper project aligns with the city’s long-term planning objective of increasing density along mass transit routes. The project strongly encourages the use of public transportation and a reduction in fossil fuel consumption by providing limited private and public auto parking options, while establishing a direct pedestrian link from the train to the building. In fact, the building’s lobby is located 228 m (750 ft) from Exposition Light Rail transit station via a landscaped pedestrian walk and direct stairs to the lobby. In this neighborhood, which previously limited building heights up to 13 m (45 ft), (W)rapper introduces a new scale, density, and multipurpose functions.
Some of the other sustainability features of the office tower are:
- Low carbon footprint. The project is designed for a lifecycle five times longer than a typical high-rise office building, resulting in a significant reduction in carbon usage over the building’s useable life.
- Leadership in Energy and Environmental Design (LEED) silver equivalency. The building exceeds all California’s stringent green building requirements and performs equivalent to a LEED silver rating.
- Reduced solar exposure. Self-shaded building configuration with south-facing offset core, exterior band structure, and inset glazing, all reduce heat from solar exposure.
- High-performance facade. Energy efficient facade with high-performance low-emissivity glass, insulative and light weight plaster clad walls, and light-colored reflective roof.
- Natural daylighting. Shallow floor plates bring natural light to the entirety of each floor.
- Flexible interiors. Column-free interiors allow maximum tenant flexibility, limiting cost and the carbon footprint of tenant improvements.
- High-performance mechanical systems. Energy efficient and scalable variable refrigerant flow (VRF) mechanical system with dedicated outside air filtration system and automated building management system (BMS) for optimization.
- Natural site cooling. Building orientation maximizes westerly breezes from the Pacific Ocean and the site’s water feature, The Puddle, provides evaporative cooling.
- Water conservation. Touchless plumbing fixtures with maximum water conservation.
- Water recycling. All storm water on the site is collected, filtered, and reused for irrigation through an on-site cistern.
- Acoustic performance. Glass facade adjacent to the Metropolitan Transit Authority (MTA) train is triple-glazed to provide quiet interiors.
- Mobility. The site is adjacent to major bike path arterials and the project contains extensive short- and long-term bicycle parking with on-site showers.
