Design Development for the Shimla House

During the concept phase, we establish the high-level gestures and themes of the project. As we progress to the Design Development phase, we add more specificity to the design. We determine floor to floor heights, window openings, and material palettes. We study cladding options, stair designs, and the usability of each space.

For the Shimla House, we broke the project down into three parts: Exterior Envelope (Architecture), Interiors, and Landscape. This allows us to have more focused design meetings and to avoid overwhelming our clients. However, it also means that we, as architects, have a critical role in ensuring the design remains cohesive across these different disciplines throughout the duration of the entire process. As we work with other designers and engineers, it’s our responsibility to be present and participate at all design meetings to make sure the overarching design vision stays intact and that the entire project is developed at the same pace.

Exterior Envelope

For the exterior design, we began with a 3D white model and studied its massing and solid/void relationships.

Our natural inclination was to differentiate the siding material by level since there was a clean delineation between floors. We chose two cladding materials: one for the upper volume and one for the lower volume.

It’s very important to develop a strategy or a set of logical rules when to help us determine where materials should go. We don’t want it to be random.

Massing Diagram

We knew we wanted the house to have a strong connection to the surrounding context, so we chose wood siding. For the lower volume, we chose a dark cementitious panel, which is a budget-friendly, durable material. We also wanted to be mindful of the changing seasons as we selected materials since the landscape is dynamic.

Exterior Material Palette

We oriented the wood siding vertically to mimic the lines of tree trunks in a forest. To add visual interest, we overlaid wood slats on the siding and spaced them at regular intervals – like a stand of trees – that gives the façade a playful effect. The slats create a rhythmic play of light and shadow as light hits them and replicates the trees in the distance. As your eyes move along the long wall, the way you perceive the slats change depending on if you see the edge or the face of the slat.

As you approach the house from the driveway, there is a nice dynamic and dramatic effect.

[Middle Image: Curtain Residence by Johnsen Schmaling Architects.
Right Image: NB Residence by Jacobsen Arquitetura. Photo by Fernando Guerra.]

While we’re determining the cladding materials, we’re working through the overall wall, roof, and floor assemblies to make sure there’s enough insulation, to ensure a water-tight enclosure, and to create a durable and low maintenance envelope.

But let’s not forget about the abundance of glass everywhere. We studied window sizes and locations as they related to both the exterior design and interior layout. With so much glazing, we needed to be mindful of the budget and thermal performance so we selected a high performing and economical Marvin window for most of the windows. This allowed us to splurged on the large pieces of glass in the Great Room which was of utmost priority.

One of the most important decisions about the exterior design was whether to use lift & slide doors or bifold accordion style doors. Our clients chose lift & slide doors because having more glass and less frames blocking the view was more important than a larger clear opening width. Lift and slide doors also offered better weather protection at the thresholds. Even with large overhangs, we get driving rain in Ohio so water intrusion was a concern.

Zoning Approval

To get approval for our modern house design with a flat roof, we needed a variance from the township’s zoning restrictions which require a 6:12 pitch on single-family residences. Local codes sometimes dictate that new homes match the surrounding neighborhood aesthetic, but we felt that our secluded lot and the diverse local architecture justified an exception.

To us, the roof pitch would not negatively affect the neighbors and would allow us to create a great, timeless home in this idyllic setting. If anything, this custom home could increase the property values of neighboring homes, making it a win-win scenario for us, the neighbors, and the township who could see higher property taxes.

Though some committee members disagreed with the design, they granted the variance, recognizing that the code’s intent.

Structural Design

Our custom home designs push structural limits, so we work with engineers to ensure they can be built. We use wood framing with steel where needed, prioritizing floor/roof depth and spans.

(Side bar: As architects, we are only specify structural designs with 2x framing members and conventional framing systems since those are covered prescriptively in the building codes. Anything more than that, we rely on engineers to help us.)

First, we established the main structural strategy for the house. For this project, we chose to frame the house with stick framed (wood) construction and intermittent steel framing as needed. Steel framing can span farther than wood in a smaller profile, but it can be pricey so we need to be intentional as we balance the design intent with the budget.

Next, we sized and designed the main structural members, prioritizing the depth of the floor and roof framing. With our T-shaped plan, the floor and roof framing were straightforward to establish a common truss depth, which determined the floor to floor heights, and ultimately set ceiling heights and number of risers.

The great room required steel moment frames due to its mostly glass walls. (Typically, wall sheathing transfers lateral loads to the wall framing and foundation. With mostly glass walls, we have less sheathing, so we rely on either posts and beams or cross bracing for support.) This becomes an important consideration when we coordinate routes for mechanical, plumbing, roof drain piping, and electrical conduit.

Interior Design

On many of our projects, we do our own interior design. For a larger, comprehensive project, we rely on outside help to aid in our designs so that we can dedicate more of our attention to the architecture and let an interior designer provide expertise in their respective creative field.

We enlisted the help of Dustin Gerken Design to help with the interior design. They are a small boutique firm that specializes in modern design and creates well-crafted interiors. They are detail-oriented and are elevating modern design in central Ohio and beyond.

Together with DGD, we established an overarching vision for the interior spaces and chose a material palette that is warm, moody, industrial, and refined.

Interior Material Palette

As we designed key spaces in the home, a distinct design language emerged. Repeating specific details or design language subtly throughout the house is a good way of visually unify it. For example, we use exposed steel plates as a nod to the industrial theme in the fireplace, stairs, and light fixtures.

While DGD focused on each room, we ensured that the material choices and aesthetics maintained the overarching design vision. We also took the lead in designing the stair and railing, which were subject to building codes regulations.

We went through several design iterations for the stair, aiming for a light, industrial feel. Initially, we designed a closed riser stair (easier for timid dogs to use), but ultimately decided on an open riser stair with wood treads and steel stringers. This design choice continued the exposed steel theme throughout the house.

Landscape Design

For the landscape design, we enlisted the services of Implement Studio to unify the vast five-acre site into a cohesive vision. We decided that much of the site should remain natural with a more structured landscape design closer to the house.

Implement Studio created areas of varying degrees of intervention ranging from simple pruning and removal of invasive species to planting beds and terraces.

Landscape Plan courtesy of Implement Studio

Because the site is quite flat, we created a large hardscaped plinth that would step down and draw attention to the change in topography where it met the softer ground.

Working with Dustin Gerken Design and Implement, we established a four foot module that repeats throughout the entire first floor (inside and out). Structural elements, windows, floor tile, terrace edges, and pool limits all relate to this grid pattern.