Miller Hull

Petal Certified Miller Hull San Diego Studio

Source: International Living Future Institute

9-16-2020 | News

Place Petal

Since this project is a tenant improvement in an existing commercial building, neither I01 Ecology of Place, nor I02 Urban Agriculture were required. Consistent with the scope of an existing structure that added no parking, shower and bike storage facilities were provided to comply with I04 Human-Scaled Living. The team contributed to the Living Habitat Exchange to meet the requirements of I03 Habitat Exchange.


The Miller Hull San Diego Studio Tenant Improvement project exceeds the 30% reduction threshold required under the Core Imperative, Responsible Water Use. Prior to our build out, the existing space  was designed with 4 toilets, at 1.6 gallons per flush. Our design reduced fixtures by 50%, dropping down to 2 toilets with a maximum flush rate of 1.28 gallons per flush. This change alone reduced water use from 4800 gallons per day down to 640 gallons per day. Additionally, each of our lavatories on the project has an aerator that sets a maximum flow rate at 0.5 gallons per minute.

Energy Petal


The Miller Hull San Diego Studio approached embodied carbon reduction through several different methods: reuse, reduction and sequestration. These are in addition to the full-building carbon offset that was purchased.

Material Reuse
The project utilized approximately 9,700 square feet of existing materials within the existing building as part of the finished tenant improvement design. These items included interior partitions, composed of metal studs and gypsum board, ceiling finishes, wall finishes, and flooring. Select light fixtures were also reused. These in-situ materials constitute an embodied carbon savings by not needing to install new items.

Carbon Sequestration
Although selecting specific carbon sequestrating materials was not the intent of our design, it can be said to have occurred through the use of FSC wood on the project. Miller Hull has been part of original and industry-leading research to help quantify the carbon sequestration benefits of the enhanced forestry practices of FSC-harvested timber. Our research has shown that wood that has not been responsibly managed has the potential to emit more green house gasses than steel in some cases. However, when we compare the FSC practices associated with wood sourced from Washington state, for example, we can see as much as a 200% increase in the carbon sequestration benefits of FSC wood over steel. Our renovation work contained a variety of FSC timber including wood studs, plywood and MDF.

One of the most significant quantities of interior finish materials on this project was our carpet. We chose a Declare Labeled, low-carbon Mohawk EcoFlex product. This particular carpet tile has 32% less embodied carbon than the typical industry baseline as reported in the EC3 tool. For just the carpeting selection, on our project alone, that’s a savings of 135 kgCO2e.


The firm’s work on other projects and evaluating embodied carbon at the full building scale has helped us to better understand how to begin tackling this problem from the design stage. We have done some work on comparing the EPD’s on major products in the project like carpeting, but where true industry baselines don’t exist, it is hard to make significant reductions based on targets.

The primary effort to reduce embodied carbon for this project was to utilize an existing building. Primary structural members were kept intact and additional finishes were not added. The team also worked to reuse existing materials where possible. FSC wood also plays a significant role in providing wood that sequesters more carbon than wood with sub-FSC forestry practices.

The space was leased as a warm shell; no mechanical or lighting system was in place. It was originally designed for a restaurant tenant – the primary façade was an extensive area of glazed curtainwall to connect occupants with the adjacent bay and marina views, and large roof overhangs provide needed shading.

Since the systems would be essentially owned by the tenants, the design concept became one driven by simplicity. From an HVAC standpoint, the desire to occupy a passively cooled space determined the remainder of the design. The HVAC system is a simple heat recovery ventilation unit providing tempered fresh air but fitted with an electric heating coil to deliver space heat through the ventilation air during colder periods. There are some electric radiators at perimeter conference rooms to supplement the heating. The passive cooling meant introducing manually-operated vent windows in the curtainwall system, which was the only significant envelope modification. The only compressor used is in a small split system AC for the server room.

Lighting design consists of low-wattage LED linear fixtures with a Lighting Power Density of less than 0.6 W/SF (although typically it operated at about 0.15 W/SF with daylighting controls). Controlled receptacles and active management of plug energy (tenants turning off equipment at night) is the final piece of the energy system design. The 24 kW PV system occupies space on one roof area over the tenant space. Panels are placed among the existing skylights. The roof is actually north facing at a 5-degree slope. Many options were considered to improve panel performance by overcoming the reverse tilt but in the end, it was proven again that a coplanar array provides the best power density. A battery system provides backup power. Later in the project, the controls of the battery were changed to help in peak power shaving; excess PV power generated between 10am and 2pm is fed back into the building between 6 and 10pm when peak power rates are still active.

Regulatory Appeals 

The design-build mechanical engineer had to convince the energy code official that we could use electric resistance heat because we were going net zero with PV.


We chose to add electric resistance heating to offset the radiant cold from the extensive exterior glazing. While this approach increased the energy budget, it meant zero refrigerants. Additionally, it felt novel to us that a tenant improvement could have the opportunity to be net zero. A willing landlord and the right design made this all possible.

Health + Happiness Petal


In terms of daylighting and access to windows, our project was fortunate to inherit a good building shell, which happened to be designed by Miller Hull ten years ago. Our new space was light-filled by floor-to-ceiling windows on nearly all sides, as well as whimsical skylights throughout. Since the space was originally intended for retail, there were not as many operable windows as our office design called for.

Part of our renovation required upgrading the storefront to have operable portions so that each space had access to fresh, marine air. The variety of operable windows and doors around the office perimeter allow staff to control their climate throughout the day and adjust to changing weather and needs for ventilation. Even the model shop has a large operable door to completely vent to the exterior.


The precision of the indoor air quality (IAQ) tests continue to be a formidable challenge. We have conducted numerous IAQ tests on a variety of projects, and are often still surprised by the results. From unplanned outdoor contaminants, to a contractor mistake and scheduling issues, each LBC IAQ test is different, and there are many ways to fail. We have found that not only do all the requirements for specifying need to be closely followed, but also details around day of testing and ensuring the contractor and tester stick to the schedule. Over-communicating and planning for this Imperative is key throughout the entire process. It can also be helpful to try to clearly explain expectations for the testing process to team members as clearly as possible, since many have not encountered IAQ testing before.


The Miller Hull San Diego Studio Tenant Improvement project was an interiors only renovation. The project allows direct outdoor access for tenants to the San Diego Harbor and Marina just outside our doors and operable windows. The climate of San Diego allows for the direct connections of nature to be realized for the majority of the year.

Materials Petal


Having worked through the Red List Imperative on numerous other projects, the challenges it presents are not so numerous as they once were. For this project, one of the biggest hurdles was introducing the Red List to a region of the country that had yet to really explore it. Prior to this Living Building project, the Miller Hull San Diego office had been involved in several projects that excluded Red List chemicals as part of Miller Hull’s standards for all projects, but our office renovation represented the first real attempt at full Red List compliance.

As usual, hexavalent chromium, particularly in metal framing, remains a great challenge. This is largely due to the major manufacturers having seemingly created some sort of agreed-upon resistance to providing a RoHS-compliant passivation coating simply because they do not want to. Also, as expected, obtaining FSC lumber was a challenge, but we have developed several strategies to try to address this. Unfortunately, it usually involves transporting the FSC wood from a further distance than we would prefer. Smaller items like various adhesives and sealants can be challenging as well, because there are many products to vet and most products are not compliant. Paints and coatings can be added to this list as well. While we identified some general interior paint products from a couple of major manufacturers that are Red List compliant, most products in this category are not and certainly not forthcoming about their ingredients. This is even more of an issue with any specialty coating. At first, door hardware was challenging as it often is, but once we decided to focus on one manufacturer—Assa Abloy, it was much simpler. Of course, there is always the difficulty with any complex HVAC or electrical item. After vetting dozens of manufacturers for many projects throughout the country over years of this work, many of them do not provide the necessary information for Red List evaluation. This industry has maybe been the slowest to make any progress or even attempt it. Larger electrical components, such as panel boards or other complex electrical items above 50v, often have very little information on their products. Both these industries also seem immune to requests for transparency or collaboration to reform.

Equity Petal


The Miller Hull San Diego Studio Tenant Improvement project was an interiors only renovation. The project scope does not include any exterior work such as roads, parking, exterior furniture. As a tenant improvement in an existing building, the project does not block access nor diminish fresh air, sunlight or natural water ways.


The Just organizations on the project were Miller Hull and PAE.

Each year, Miller Hull donates a significant portion to charities. We support numerous organizations through annual contributions, sponsorships, board and volunteer involvement, and are active participants in a range of conservation and service projects. To meet the additional LBC 4.0 requirements, our contractor on this job, DPR also made two donations that went beyond the 0.1% of the project cost.

More information about Miller Hull’s charitable giving and volunteer activities can be found here:

Beauty Petal


Celebrating the view of San Diego Bay, the new Miller Hull San Diego studio creates a collaborative, open office setting that engages and inspires our studio and its visitors.

Located in The Wharf at Point Loma Marina and built in 2009, it is actually the firm’s first project in San Diego, and was designed by the firm’s late founding partner, Robert Hull. The tenant space had never been built out for a tenant, which allowed  the design team to see and walk through the entire space freely. As one enters the space, it is immediately apparent how the original design takes advantage of the proximity to San Diego Bay and surrounding outdoor spaces. The goals of the project were to create a flexible open workplace that fostered collaboration and innovation, reflected the highest environmental design standards, highlighted the site’s unique attributes, was timeless, and provided a place where Miller Hull’s diverse clientele could be inspired to collaboratively create unique solutions specific to their needs and reflective of their identities.

The design is simple without the pretense of being on the cutting edge. The existing space is composed of two areas with different heights. The east side is one story, with the south portion wrapped by storefront windows. There are separate tenants located on the second level and to the north. The west side of the space is a two-story volume surrounded by curtain walls along three sides, including circular skylights that allow even more natural light to come into the spacious area. Aside from the obvious benefits of 24/7 views of the bay and marine life, the studio has the advantage of having a multi-sensory experience being so close to the water. Rippling tides constantly reflect interesting patterns of light into the space. The open windows also allow the ocean water smells to permeate into the space.

Daylight and fresh, outside air can be accessed from almost anywhere in the space through manually operated windows, as well as doors. As part of the Materials Petal, the design team put extensive effort toward eliminating harmful chemicals included on the Living Building Challenge Red List, using regional materials, and sourcing wood certified by the Forest Stewardship Council. Naturally, the result was timeless elegant finishes throughout.

Each workstation, meeting, gathering, and collaborating space is naturally lit and ventilated, enhancing well being and productivity. The workstation area, where most of the staff spend the majority of their day, is located in the single-story area, which feels protected and secure while offering the best views and access to natural ventilation. The taller space is used for gathering places such as the conference rooms and the kitchen, which also fronts the bay.

In order to encourage healthy movement throughout the workday, storage, supplies, printers, copiers, and materials libraries are in a centralized location in the northeast hall. Counter-height collaboration tables located in the work studio allow people to reposition how they work and provide additional meeting areas. Artwork and architectural scale models are displayed throughout the space and notably in the combined ‘Design Panel’ gathering space and reception area. This area highlights the culture of craft in model-making, as well as works of art by local regional artists. The current works on display are pieces made or printed with found objects in both San Diego, California and Tijuana, Mexico.


Read the full story at International Living Future Institute