Wading Through Green Standards...

You’ve probably heard of LEED, (Leadership in Energy and Environmental Design), and maybe if you’re in California you have heard of GreenPoint Rated or the eminent CALGreen Code, but wrapping your head around how these standards compare and what they mean to your building project can be a big task.  In this article, I’ll try to break it down a bit.  For more detailed information, please visit the web sites of each compliance organization: LEED, GreenPoint or CALGreen

LEED, developed by a non-profit organization called the U.S. Green Building Council, was really the forerunner in developing an industry standard for sustainable building practices in the United States.  GreenPoint Rated (GPR) is a system used for houses and developed by Build It Green, another non-profit based in California, with the goal of creating a standard that would be less expensive and therefore more accessible to homeowners.  CALGreen is a building code that will become effective in California for both residential and commercial buildings on January 1st, 2011.  Some municipalities in the Bay Area are even requiring permit applicants to get certification from GPR and/or LEED as a way of ensuring that CALGreen standards have been met.

Both GPR and CALGreen systems of measurement are based loosely on the LEED standards, but there are some differences and modifications made to clarify or make easier the systems of measurement that are in place.  For simplicity, I’ll compare the residential measures as a common base for all three systems.   All systems break green building components down into areas of sustainability that they are addressing with varying names and sub- categories.  However, the general concept is shared: sustainable building practices fall into these categories:

  1. Planning/Site/Community
  2. Water Efficiency
  3. Energy Efficiency
  4. Material Resources
  5. Environmental /Air Quality

GPR arranges their checklist in a way that relates more closely with building systems themselves such as structural frame and finishes, but are then cross-referenced with one of the above categories.   All of the systems have mandatory or prerequisite measures that must be met, and the two voluntary systems (LEED and GPR) have additional strategies that go above and beyond to earn points.  A minimum number of points is required for certification, and the more points earned the higher the level of certification.

Since LEED and other green building certification systems have begun gaining popularity, there have been a number of articles and independent studies published on the value added by achieving certification, such as “An Inconvenient Value” by www.AwarenessIntoAction.com  and “The cost & benefit of achieving Green buildings” by Davis Langdon.  We hope the trend continues to catch on and the up-front cost continues to come down as demand for sustainable building materials and methods continue to rise.

Now let’s dig a little deeper into the subcategories and the particular goals of each.  The charts below are not meant to be comprehensive, but instead give an overview, hitting the highlights of each system.   Note that The CALGreen system has two “Tiers” that can be sought, which require additional prerequisites.  I’ve included these prerequisites under ‘additional points/measures’ in order to maintain clarity of the basic requirements in the charts below.

Bridgett Shank works at Feldman Architecture and is a frequent contributor to Green Architecture Notes.

Sustainable Sidebar: Add a Little ‘Green’ to Your Home, Inside and Out...

Advances in green technology and a fondness for reused or reclaimed materials have led to more innovative and creative sustainable products for the home. As a new addition to Green Architecture Notes, we will be posting a new section on products that we find to be perfect examples of how green IS beautiful, practical, and inspiring.  In this post, the adaptive reuse of reclaimed materials yield stunning furnishings and fixtures which divert materials from landfill and reduce energy used in the production of new materials.

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Products in Top Row:

left – The Scrap Light collection from Graypants demonstrates how simple pieces of salvaged corrugated cardboard become mesmerizing. These lanterns create stunning patterns with light and shadow in any space.

center – The Studio Sectional from Environment Furniture has a relaxed, informal quality. Upholstered with recycled army tent canvas fabric, the distressed and weathered characteristics will continue to develop and patina over time.

rightUrban Hardwood is best known for breathing new life back into trees that would typically be heading straight to the landfill. The Sycamore Slab coffee table positions a pair of slabs side-by-side and fastens them together with steel infill. This simple design lets the wood’s beauty speak for itself.

Products in Bottom Row:

left -The Asturia Armchair from Espasso, designed by Carlos Motta, is strong, durable, and elegant. Built from reclaimed and demolition woods collected in urban centers like Sao Paulo, this chair is suitable for both indoor and outdoor use.

centerGraypants is redefining the “recliner” with their latest design, the slice chair. Constructed from scraps of flat sheets of plywood, the slices allow the ottoman to slide out, creating a lounge chair.

right – Ending with a PUNCH! of color.… We introduce an area rug from the Color Reform Collection by ABC Carpet. This rug is hand-woven from recycled Indian Sari silk, then over-dyed to create a powerful statement packed with mono-chromatic vibrancy.

Cork: What makes this material so special?...

Cork is a fantastic, 100% natural, material that has been used as an insulting material for years, although is not well known by most of the people working on sustainable and zero carbon projects.

So what makes this material special?

Cork is the bark of Cork Oak (Quercus Suber), collected every 9 years and later transformed and adapted to different uses. During its life, cork retains an elevated portion of CO2 and requires very low energy to be transformed.

Cork insulation

The most common use in construction – as a thermal insulation material – is Insulation Cork Board (ICB). This material is produced using raw cork (which can be a sub product of the cork stopper industry) in granulated form that is placed in autoclave where it stays for 20 minutes under vapor at 360º C (680º F). As the cork starts to expand and forms into blocks, it starts to agglutinate by means of its natural resin and also gains its characteristic brown color. The process is free of any artificial chemicals keeping the material 100% natural.

Cork is particularly resistant to insects and maintains its characteristics over time. In 2000, in the north of Portugal, a very large cold store built in 1969 was dismantled. Cork was used as thermal insulation and it was fully recovered to produce new cork based materials. What is remarkable is that the cork was analyzed in laboratory and had exactly the same characteristics as new cork meaning that its use hasn’t diminished any of its qualities.

In a recently completed K-12 school renovation project where we used cork extensively as a thermal insulation material on roofs (metal and concrete slab), we came to the following conclusions:

• The material behaves very well during construction, in good or bad weather;

• No special skill is necessary to apply this material;

• Any cuts or changes needed during work are easily achieved on site.

In an ongoing project we’re using the same material as a roof and facade insulation as part of a render system and expect to achieve a very high performance for the building.

In recent years, Portuguese architects have been exploring this material as a cladding. The Portuguese pavilion in the Hanover Expo 2000 used cork blocks as a facade. Recently, the Portuguese Pavilion in the Expo Shanghai which was entirely covered in cork panels won a design award and also in Architectos Anonimos ‘s Cork House which is shown below.

Coimbra, Portugal - Pavilhão de Portugal Expo 2000, Álvaro Siza & Eduardo Souto de Moura.

As a conclusion, we can say that cork is a natural, recyclable and environmental friendly product, highly adequate for green or zero carbon projects, as insulation and cladding material, with a guaranty of total reuse in the end of the building life-cycle making it a very good cradle-to-cradle material.

Cork House by Arquitectos Anonimos, Portugal.

For more information from a cork supplier, see Amorim Cork Composites.

Fernando Ribeiro studied in Portugal and England where he obtained a Master Degree in Architectural Design after which he worked in Macau on several high profile projects. He is the co-founder of Arqwork Arquitectura, a practice engaged in a broad range of projects from K-12 schools to retail spaces.  His practice is driven by passion in designing buildings and enhancing people’s lives. Fernando’s interest in sustainable design led him to engage in developing a more practical approach to architecture through the use of simple technical solutions and natural materials.

Tools of the Trade...

One of the joys of working in architecture and design is experimenting with material and color on both big and small scales.  While the computer is the primary tool for cranking out plans and sections, pens, pencils, and watercolors are found at every designer’s desk at Feldman Architecture.  While working on preliminary designs for a project, we find that pencils and pen are the quickest way to depict several options and convey them to the client.  When running to a job site, picking up a pen and sketchbook is required.  And in an office of 10, there are nearly 10 different boxes of pens and pencils to accommodate the designers’ preferences!  Here are a few of the staples found in Feldman’s office.  – Hannah

Tools-11. The Pentel Sign Pen and Prismacolor pencils used to sketch an option for one of Feldman’s kitchen remodels.
2. The Uni-Ball Vision Elite is available at any office supply store and was used to sketch the Cliff House from Sutro Baths.
3. Chartpak Ad Markers and Letrasets Tria markers are ubiquitous at any architecture or design firm and are typically used for rendering plans and elevations such as Feldman’s proposal for this renovation.

Tools-24. A Papermate Flair felt tip pen and a traveling set of MiniStaff pencils by the Eye Ball Pencil Co. are perfect for sketching on site.  This pencil set includes eraser and sharpener so you won’t forget as you run out the door.
5. When traveling, size and weight are always a concern.  Many designers travel with a small sketchbook (this one is just 4”x3”) and a Faber-Castell Pitt Artist Pen for capturing great monuments such as Angkor Wat.
6. Another great travel item is the Van Gogh watercolor set which fits into your back pocket and includes a fantastic array of color.

Tools-37. Uni-Ball Deluxe Rollerball pens are also widely available and allow for quick massing studies like this one for a new home in Carmel.
8. If you can’t decide whether to carry watercolors or color pencils, there is no need to compromise with Cretacolor’s Aquarell watercolor pencils.  Just add the color pencil to your drawings and brush with water.
9. The ideal sketchbook stays closed in your bag to protect the ideas inside.  Three of our favorites are a traditional Venetian leather bound book with leather wrap, a Holbein sketchbook (available with many different paper types – here in grey), and the current trendy favorite Moleskine (available in many sizes, shapes and colors – here in red).

Green Focus: Green is Beautiful by Claudio Santini...

Green is BeautifulAs a new segment of Green Architecture Notes, we plan to periodically share images from talented photographers and authors who are focusing on Sustainability and Design.  Our inaugural post is drawn from the aptly named Green is Beautiful book by photographer Claudio Santini and Dafna Zilafro.  Green is Beautiful offers 30 stunning residences each exemplifying sustainable design.  Below we offer images from a few favorites.  For more information, see Claudio Santini’s website, www.claudiosantini.com, or Amazon.com.




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Description of Images Top Row

leftCarver + Schicketanz Architects creates a warm modern space that ties expansive views in with tactile, rustic salvaged materials in the Treadwell Residence.

center left – At Sintesi Design’s Kuperberg Residence, large pivot doors and a shade trellis blur the boundaries of indoor-outdoor living.

center right – Working within a tight urban lot, Zack DeVito Architects masterfully directs daylight from overhead to bring natural light deep into the Chattanooga Townhouses in San Francisco.

right – Pugh+Scarpa incorporates clean energy generation into the Scarpa Residence by wrapping a photovoltaic array across the roof and down one façade of the building.

Description of Images Bottom Row

left – O plus L’s Nordine Residence features clean lines and celebrates the use of thermal mass in a board-formed concrete fireplace and concrete floors.

center left – Stone walls and concrete floors make up a simple and elegant material palette for the Piperno Residence by Luigi Villano.

center right – Through careful siting and the use of a green roof, Feldman Architecture allows House Ocho to sit quietly in the landscape, while views of the lush terrain dominate the visitor’s experience.

left – Recycled timbers from an old barn span the dining room and frame the sweeping view of the Petaluma River at the Sutton Residence by Sutton Suzuki Architects.

Hannah Brown is a current contributor to Green Architecture Notes, works with Feldman Architecture and teaches at California College of the Arts in the Architecture Department.

Green Business Spotlight: Energy...

From time to time, the Editors of Green Architecture Notes turn the spotlight on businesses where sustainable products or technologies have been implemented in a move toward a more environmentally-conscious practice. Mueller Nicholls, a General Contractor and Cabinet Shop in Oakland, California, is one such business which is leading by example through a pioneering effort to reduce their reliance on fossil fuels.

Solar panels atop the Mueller Nicholls Builders' cabinet shop

A general contractor and cabinet shop will typically use a significant amount of energy for several functions, most notably for running portable and stationary tools, powering computers, illuminating facilities, and shuttling workers and materials to and from jobsites.  At Mueller Nicholls, we’ve long focused on making our operations more sustainable, and recently, we’ve concentrated on greening up two conspicuous sources of energy demands in our business.  In the spirit of inspiring other companies to do the same, we wish to share some key points from our experiences investing in alternate and green sources of energy to run the shop and office as well as some of our company vehicles.

 The cabinet side of the Mueller Nicholls’ business uses roughly 10,000 KW of electricity every month.  We’ve been eying the sun for quite some time as a potential power source, and in the summer of 2008, we took the plunge and installed a complete photovoltaic solar system.  The system generates 90% of yearly energy needs; we’re thrilled to have cut our dependency on less renewable sources of energy by such a large margin.

 

Although we focused on the sustainable concerns when installing the systems, financial considerations also came into play.  At that time, the federal tax credits were substantial and just about to expire.  We determined that the payback period would be a brief eight years (we’re 25% there!), and the idea of the monthly payments going to a local bank as opposed to a large utility was attractive.  For the PV system, the monthly cost of financing roughly equals the monthly power bill prior to installation of the system. Mueller Nicholls’ location in West Oakland made the logistical considerations very easy.  We have 250 panels that fit easily on the 16,000 square foot flat roof of the cabinet shop and also plenty of space for the inverters at the electrical panels.  The entire crew is aware that we’re getting our energy from the sun, which is a source of pride for green-minded employees.

With regards to our transportation, in 2006 we began replacing our standard SUVs and sedans in order to upgrade to hybrid vehicles.  Having company cars at the office allows a large number of employees to bike to work – sometimes up to seven employees out of twenty-two – and then to share the cars as necessary.  At this point in time, there are four hybrid company vehicles and our fleet gas consumption has decreased by roughly 1,300 gallons per year.  At $3.00/gallon, this saves $3,900 per year in fuel costs.

 
 

 

One of the four hybrid vehicles in the Mueller Nicholls fleet

When we purchased these cars, electric cars were less than practical from many standpoints.  Hopefully by the time we need to retire this fleet, we’ll be able to switch to electric cars.  We also have two diesel delivery trucks, which we plan to convert to bio-diesel as this option becomes financially feasible.  We look forward to the day when we can expand our PV system in order to charge electric vehicles and have portable PV solar panels as a way to provide power to a job site.

While our journey towards using more renewable energy sources for our power consumption is far from over, we’re pleased to have taken these first steps.  In a marketplace flooded with companies that tout their sustainable practices, we believe it’s crucial to put our money where our mouth is and to reduce the impact that our cabinet and construction practices have on the planet.

Jill Moran is a construction professional with 20 years of varied experience in high-end residential remodeling. Her recent entry into motherhood, timed precisely with the downturn in the local construction industry, has resulted in a slight re-engineering of her career.  She currently works closely with the management team at Mueller Nicholls, with an emphasis on communicating to the world at large about residential remodeling.

Fly Ash in Concrete...

Slag pile in front of concrete batch plant

There has been a lot of discussion recently about fly ash in concrete as there are concerns about heavy metals in this by-product of coal fired power production. 

“Replacing Portland cement is a high priority for all of us…” Russell Perry, Smith Group.

 “The Environmental Building News” (Alex Wilson) continues to support the use of coal fly ash in building materials as long as:

a)      the use of fly ash reduces greenhouse gas emissions elsewhere in the materials stream; and

b)      the fly ash is chemically or physically locked up so that the risk of leaching is kept acceptably low.

Slag is a byproduct of steel smelting

A 2008 study by researchers at The Ohio State University found that fly ash concrete exposed to heat through steam curing retained 99% of its mercury content and showed final emissions similar to those of common soil.

A follow up study at Ohio State in 2009 that looked at both gas emissions and liquid leaching showed that the amount of mercury emitted from fly ash concrete was independent of the amount of mercury in the cement.

In California and much of the Western United States, the primary cement substitute in concrete is slag.  Bode concrete, for example, advertises a “green” mix that is 30% slag and 15% flay ash, in place of 45% of Portland Cement. 

Molecular structure and relative scale of concrete additives

Slag is byproduct of the metal smelting process.  Common components of slag include the oxides of silicon, aluminum, and magnesium, as well as sulfur, which is always present. Slag also contains phosphorous, calcium, ash, remnants of flux materials such as limestone, and remainders of chemical reactions between the metal and the furnace lining.  Slag cement has actually been used in concrete projects in the United States for over a century. The earliest use of slag cement was documented in 1774, when it was combined with slaked lime and used as a mortar. Slag cement was first used commercially in Germany in the 1860s, and it was such a success that engineers in 1889 decided to build the Paris underground metro using slag-lime cement.

Ross Levy, principal of LSarc in San Francisco, is dedicated to progressive, sustainable design and is a Contributor to Green Architecture Notes.  For more information, please see Ross’s bio on the Contributors page.

Designing Living Roofs – Part 2...

Entry Walk towards House Ocho. Photo by Paul Dyer.

I’ve had several reasons for designing living roofs and have faced many challenges in implementation. Luckily living roofs can come in many forms and serve many purposes. In this post, I will try to briefly walk you through the second of my forays into this exciting and challenging subject.

For our House Ocho project in Carmel Valley, there were many reasons that we decided to design a living roof. Among those reasons, thermal properties, habitat conservation and fire protection were all important. But the driving reasons were visual. Placing meadow grasses and wildflowers on top of the buildings allowed us to insert our program into the stunning natural site that straddled a grove of costal live oaks and a steep meadow with far less visual impact. Because the house is sunk into the steep hillside and is approached from above, its roofs rather than any facade create one’s initial impressions of the house.

View of Roof and Skylights. Photo by JD Peterson.

Most of the downhill sides of the house are glazed windows and doors, and because of the seismic activity in the area, we needed to minimize the extra roof loads that deep soil would create. However, we wanted to create a roof garden that had the feel of a native meadow so that the house would blend in with the adjacent landscape.

We worked closely with Paul Kephart of Rana Creek to design the whole roof system. Paul has decades of experience designing living roofs and is responsible for, among many other projects, Post Ranch Inn, The Gap Building in Daily City, and Renzo Piano’s new Academy of Sciences in San Francisco’s Golden Gate Park. For House Ocho, we settled on using six inches of a lightweight soil mix that contained pumas to reduce its weight. We also used a water retention layer that holds a portion of the water in small cups and keeps the soil moist. This basically allows a shallow depth of medium to support plants in a way that is comparable to deeper soil. For plants, Rana Creek worked closely with our landscape designer, Loretta Gargan, and we ended up with a mix of native grasses and wildflowers, as well as strawberry and yarrow. See below for specific planting mix as well as roofing specs.

House Ocho in the Landscape. Photo by JD Peterson.

House Ocho:

Intentions: mostly visual, but also habitat and fire protection

Challenges: structural, waterproofing

Solution: American Hydrotech, 6″ of soil, complex mix of native grasses, wild-flowers, and strawberries

OCHO TECHNICAL INFO

The waterproofing membrane is American Hydrotech MM6125 followed by a Hydroflex30 Protection Course and Root Stop WSF40.

The Drainage system is Floradrain FD40 underneath the growing medium layer and ¾” to ½” gravel with perforated pipe and surface drains at the roof’s edges.

Detail of Roof. Photo by Feldman Architecture.

The perennial plant species selected for the roof like Sand Sedge, Pt. Joe Fescue, Yarrow and Wild Strawberry are typical of the Oak Woodland understory and representative of the Monterey Peninsula region flora.

A host of annual wildflowers were over seeded in the fall and by springtime tidy tips, lupine, poppies, and goldfields surprised the owners with a colorful spring bloom. These annuals continue to sprout and flower each spring.

Jonathan Feldman is Editorial Director of Green Architecture Notes and Principal of Feldman Architecture.

View of the house and roof from the entry path. Photo by Feldman Architecture.

View of roofs from top of entry stair. Photo by JD Peterson.

View across the roofs. Photo by Paul Dyer.

View of roof from meadow. Photo by Feldman Architecture.

Front path and house at dawn. Photo by Paul Dyer.

end

Designing Living Roofs – Part 1...

Rooftop Garden over Garage

I’ve been exploring various aspects of living or green roofs since I first started my own architectural practice about ten years ago. In fact my very first project was to fix up a shingled Victorian in San Francisco. It had a tiny garage in front of the house dating back to 1912 and a nice garden that wrapped around the garage. Wanting to expand the garage to fit two cars and occupy the entire footprint where the garden stood, I decided to make the roof of the new garage a giant planter. 

House before renovation

There have been many reasons which led to planting rooftop gardens over the years. In this first project, I valued having a nice green space in the tiny urban lot. I also felt strongly pushed to design in a way that begins to counter the urban heat island effect resulting from the over-paving of our denser developed areas. San Francisco also suffers from a rare policy that requires all roof water to be diverted into our sewers and then treated in sewage treatment plants – an extremely energy-intensive process. When we plant gardens on roofs, much of the rainwater is taken into the garden where it feeds the plants, evaporates into the air or, if designed properly, recharges the city’s ground water. 

Concrete planting structure before waterproofing

Placing what is essentially a large planter on top of a building is inherently challenging. Water is heavy and we must design a structure that can support the weight of a fully saturated planting medium and which will protect from any lateral wind or seismic loads that might occur during a deluge. Protecting against plant roots as they try to work a way through waterproofing is also a concern as is guarding against the sharp tools gardeners use which are not friendly to most roofing materials.

Plantings just after completion of construction

The first fix up project was a good first living roof project because I was only working over a garage and a little moisture seeping in above cars is much less problematic than similar leaks above living spaces. I essentially ended up building a concrete bunker in the side of a steep hill. This allowed me to have generous soil depth to accommodate large plants and their correspondingly large root structures. Typically, we are pushing to minimize soil depth in order to reduce the structural requirements. Since the garage was holding up the existing hillside and the house above, we ended up with a sloped garden whose depth went from 18 inches in the front to about twelve feet deep at the rear. Subsequently, we could plant shrubs and even substantial trees. For waterproofing, we used a torch-down membrane and covered it up with a drainage mat and a root barrier. We filled the planter with a conventional planting soil that was sprayed on top of the garage with a gunite hose. The plants consisted of trees, bushes and a fast-growing iceplant that served to stabilize the sloping soil.

View of Plantings Above

In subsequent projects, I have had different reasons for designing and implementing living roofs, and have faced different challenges. I will follow-up with accounts of other green roof projects shortly. Stay tuned!

The garden after the 1st year and years later

Jonathan Feldman is Editorial Director of Green Architecture Notes and Principal of Feldman Architecture.

Cottage On The Green...

cottage entranceMy wife, Cathy, and I really liked our one-story cottage near downtown Palo Alto, but the floor plan didn’t work for us at all. The most direct path to the backyard was through the master bedroom, and loving to backyard-entertain as we do, running through our bedroom with plates of meat headed to the grill quickly lost its appeal. Also, our house cost us a fortune to “heat,” and we still froze our keisters off every winter.

When we hired Drew Maran Construction (DMC) to execute the remodel, all we wanted was a beautiful, warm-modern house. We didn’t set out to be supremely green. But Drew’s level of knowledge, and his willingness to teach us about the ultimate outcomes of our choices, had a huge impact on the greenness of our project. As the remodel progressed, we began to consider “green” in every choice we made, and we’re glad we did. The house is warm, comfortable, and more beautiful that we could have imagined. We refused to compromise on design or aesthetics for the sake of being green, and in nearly every case we ended up with both!

The decision we agonized over most was finding a heating system that would work the best and be energy efficient. We went with hydronic heat, embedded in thin gypcrete poured on top of the subfloor, powered by a condensing boiler. This system was definitely more expensive up front, but it was hands-down the best decision we made. Our new house is wonderfully warm and comfortable. We’re heating a 65% larger house and our utility bills are about the same as they were. We’re planning to install solar photo voltaics, too, to reduce our energy usage and utility bills even more. We totally nailed that one in terms of both function and green.

Another big decision was to deconstruct the old house instead of demolishing it. Drew advised us that we could offset much of the additional cost of deconstruction by donating the saved materials, and taking a tax credit. He was right. Not only did the tax credit offset the deconstruction cost—but we kept a lot of material out of the landfill. In the final analysis, this green choice also saved us money.

We do have a few “woulda-shoulda-coulda’s.” We love our Blomberg windows, but we might have been able to go even more green there. Also, since our house is so well insulated, we probably should have installed a “heat recovery ventilation” system; condensation can be a problem in certain low-traffic spots during the winter.

That said, we’re absolutely thrilled with our home. The new layout works even better than we’d hoped. When the house won the Sustainable San Mateo 2010 Green Building Award, it was (organic) icing on the cake!

Bruce Schena is an inventor, entrepreneur, and engineer with multidisciplinary interests and experience spanning robotics, medicine, business, consumer product design, haptics, wood- and metal-working, modern sculpture, and architecture. Bruce has Bachelor and Masters degrees from MIT, and was the first to receive the Degree of Engineer in Product Design given by Stanford University. He holds 71 issued US patents with over 50 additional applications pending. Bruce has worked as a freelance design & engineering consultant in the San Francisco Bay Area and is currently one of two Engineering Fellows at Intuitive Surgical in Sunnyvale, California. His responsibilities include defining and inventing next-generation daVinci® surgical robot architectures and technologies.

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