Editor’s note: In 2024, sustainability is no longer an option, but an integral feature of any custom-designed home. Caulen Finch, AIA, an award-winning architect within Maugel DeStefano Architects’ renowned Portsmouth, NH-based custom residential team, talks with us about sustainability.
Question: Sustainability was just an idea about 20 years ago. Now, it has become a way of life. People are seriously thinking about it because of rising energy costs and climate change. What are you noticing in the custom-design residential market?
Caulen Finch: I think it’s good to start with the essentials of sustainability and what kind of marketplace we’re coming from. In the ’90s, energy was very cheap. At the turn of the century, the effects of climate change became more evident, both in terms of energy costs and public awareness. The renewed interest in sustainability is built upon the environmental movement of the 1960’s and ‘70’s, driven by rising energy costs and a growing sense of social responsibility. Many of Maugel DeStefano’s clients recognize the importance of sustainability, and we help them turn their values into real-world design decisions for their projects.
While our custom residential clients today have a sustainability mindset, 15 or 20 years ago people were less focused on sustainability in their homebuilding approach. Back then, a beautiful beach house was the primary focus, with sustainability a minimal concern. Today, our clients increasingly seek designs that prioritize both aesthetics and minimize the environmental footprint of their project.
Q: What is motivating people to ask for sustainable homes? Is it cost? Is it climate change? Is it their conscience?
CF: Our discussions with clients about sustainable home architecture start from a place of conscience and social responsibility. We’re seeing that the general education of our clients on climate change has increased—and they’re looking to Maugel DeStefano to provide the expertise on the design and the environmental footprint of their projects.
Q: As an architect, what type of sustainability challenges you are facing?
CF: One of the biggest challenges in sustainability for architects is showing the value of investing in building components that the client may not see but will improve the performance of the home. For example, investing in a wall assembly with a higher insulation value not only reduces your environmental impact, but it also creates a more comfortable home, improves air quality, lessens noise, saves costs on utility bills, and provides a more consistent temperature throughout the year. These benefits translate into a more enjoyable home. So, our recommendation to spend additional money on a more advanced building envelope is well supported by the benefits that the client will experience. Thinking about the
lifecycle cost savings can also help make the initial investment worthwhile, and it can often be the tipping point towards a more sustainable home.
We’re also constantly educating ourselves about newer technologies. New England’s vernacular architecture was designed with an understanding that air and moisture would seep through. This was a reality addressed through passive (solar orientation) or active (fireplaces) methods for managing temperature and ventilation. Throughout history, when resources are limited, architects have favored passive design strategies. This focus on passive design aligns with today’s emphasis on sustainability.
Building codes and materials have significantly evolved in recent decades. Our understanding of wall systems allows us to create a tighter building envelope, almost completely isolating the interior from the exterior. While this offers many benefits, it also presents new considerations.
For instance, in these tighter buildings, proper vapor barrier placement becomes crucial to manage moisture. Additionally, careful selection and compatibility of materials within the wall system are essential for long-term durability.
The key to sustainable architecture lies in embracing innovation and the knowledge of the past. Architects must leverage both advanced materials and time-tested passive design strategies that have been honed for centuries.
Q: What are some of the key elements of a sustainable custom residential home?
CF: I would say that one of, if not the key element of a sustainable custom residential home is the building envelope. Ensuring you have proper insulation, proper moisture management, and proper air sealing. You don’t want any air that you spend money on conditioning just leaking out through the envelope—whether it’s the windows, the doors, the roof, or the wall assembly. Consistency is important, too. You don’t want to design a robust wall assembly, and then have a lesser window; it defeats the purpose and ends up wasting material. So, we need to match the window to the wall assembly.
In “The House on The Point”, for example, we utilized a double-wall assembly. We essentially built a structural wall and then put another wall inside so that the insulation thickness increases significantly. We selected a robust triple-paned window with a very low U-factor. You don’t always need to do a robust window like this on a home, but on walls with a high R-value, such as the double wall, sometimes they can really be a smart choice. It is important to tailor each building component to the specific needs of the project. After all, every project is unique.
Q: Can you talk a little bit about passive houses? Is it applicable to custom residences?
CF: Yes, definitely—even when it’s not requested by the client or required by code. As architects, we try to use a lot of the elements of a passive house in our home design—a high-performance envelope and windows, proper mechanical systems with heat recovery, an air-tight envelope, and limiting thermal bridges. Environmental consciousness is ingrained in us during our education as architects and at Maugel DeStefano we implement that sensibility into our homes.
Q: What’s the difference between net zero and sustainability?
CF: Net zero and sustainability are different but have similar overarching goals. “Net zero” produces as much energy as you consume. It’s also possible to be “net positive,” but that’s something more challenging to achieve. “Sustainability” is having a goal to minimize your environmental impact.
Net zero and sustainability go hand in hand. Anyone aiming for a net zero home prioritizes minimizing their environmental impact, which is the core value of sustainability.
Q: How do solar panels fit into high-end custom residences?
CF: For its passive benefits, we take solar orientation into account when we are placing a building on its site as much as possible. Sometimes there are site restrictions that mean we can’t get the optimal orientation, or there are roof lines that don’t allow for maximum solar panel productivity, but we make it work as optimally as possible. Solar panels have come a long way from what they once were, and they continue to improve in efficiency. And even during dark New England winters, they can help offset power pulled from the grid.
Q: What about the look-and-feel of solar panels from an aesthetic point of view?
CF: The look of solar panels can be an issue at times in this market. Solar technology, however, is changing, and new products are constantly hitting the market. There are a few manufacturers coming out with a solar tile that looks like a traditional asphalt or slate shingle. Maybe in the future we’ll see some solar panels more closely aligned with the traditional-style home aesthetic. For now, it takes the right client, the right aesthetic, and the right site with good solar orientation for solar panels to align with the design of the home.
Q: Can you talk about sustainability and the size of sustainable homes?
CF: I know people say size matters, but it’s not always necessarily the truth when it comes to sustainability in custom homes. It’s about how you design the building—how it’s insulated, how it’s ventilated, how it’s powered, and how it’s built that’s important. Bigger isn’t necessarily bad for energy efficiency, but it is something to consider. If the goal is to be Net Zero, then the size of the home and the size of the system offsetting the energy consumption must align. The key factor is the building envelope. A well-designed large home with a tight envelope can use less energy than a poorly designed smaller home. Building shape also matters. A compact design minimizes the envelope surface area, but even an elongated plan can be energy-efficient with the right envelope and design strategy.
Q: What are some of the myths about sustainable custom residential homes?
CF: There are a few common myths: It doesn’t work as advertised, it’s too expensive, it’s complicated, and it’s unattractive. These beliefs are not true. Sustainable design in architecture can work. Sustainable design prioritizes smart use of space and natural elements, often leading to more functional and beautiful homes. Another misconception is that sustainable design is inherently expensive. While some materials or strategies may have a higher upfront cost, they often come with lower energy bills, saving money in the long run. Ultimately, sustainable design isn’t just about the environment; it’s about creating healthier, more efficient, and cost-effective homes for people to live and thrive in.
Our challenge is educating our clients and illustrating the value of spending money on insulation in their walls or a geothermal system. Investing in things that they’re never going to see can be a tough sell, but the benefits provide them with a better, more comfortable home in the end.
Q: Are you designing any geothermal homes currently?
CF: Yes, we are designing geothermal homes, and a great example is the Net-Zero ready home we named “The House on the Point” in Portsmouth, New Hampshire. The house is special. I absolutely love it. If one of my clients asked me what my dream home would look like, I would say the 4,000 square-foot “House on the Point” would be pretty darn close. It features a double wall system and geothermal heating and cooling.
In New England, geothermal is beneficial. It takes the edge off your air conditioning in summer and your heating in winter because you use the ground as a heat sink. This system acts like a natural thermostat for your home, leveraging the constant ground temperature of around 55°F.In the summer, you’re extracting hot water out, cooling it down to 55° in the soil, and bringing it back into your house. During the winter, the system reverses the process, pulling heat from the earth to help warm your home comfortably. This reduces your reliance on conventional heating and cooling systems, leading to lower utility bills year-round.
Q: What are some of the sustainable features of The House on the Point?
CF: I would say the number one sustainable element at “The House on the Point” is the building envelope. As we talked about earlier in the passive house discussion, the building envelope is usually at the top of the list as the most important sustainable feature. The house features a double wall system for increased insulation and two smart air barriers for vapor management and to prevent air leakage. The site allows for great solar orientation for solar panels and passive heat gain. We designed larger windows on the south side, bringing in solar heat gain in the winter, and smaller openings on the north side to reduce heat loss—the site really worked well for that. For mechanical systems, we’re using a geothermal system to take the edge off in extreme heating or cooling days, with radiant heat and efficient VRFs with energy recovery. It really checks all the boxes for a sustainable home in New England.
Q: What about sustainable materials at The House on the Point?
CF: The exterior siding we’re using is a fly-ash byproduct. It is a byproduct of coal combustion, which is bound together into boards. It features 70% recycled content, which is phenomenal. We’re also using Shou Sugi Ban, which is a Japanese traditional charred siding. The wood that is used is called Kebony, a pine board treated with a biobased alcohol that, under pressure and heat, binds the cells together. This transformative process allows the fast-growing softwood to take on the qualities of a tropical hardwood.
The Kebony is then charred in a traditional Japanese technique used historically in shipbuilding and homebuilding. The result is sliding that is insect-resistant and rot-resistant.
The modification of fast-growing plants and commercial by-products into sustainable and durable building materials is an interesting trend we’re seeing in architecture now. And, in the case of The House on the Point, it adds texture and a sustainable element to the siding of the home.
