Which way do you run the streets to maximize solar exposure for dense Net Zero development?
Common wisdom states that the optimal streets run east west, which makes sense if you’re the house on the north side of the street, because there’s nothing shading your house, garden or solar panels. However, living on the south side of the street, you suffer from north facing gardens and probably some shading unless the lots are 5000sf or greater.
Critically, 10 dwelling units (du) per acre is the density with enough inhabitants to support a bus service (*1), a key part of the sustainable urbanist vision for transit, pedestrian & bike use, rather than private cars. An acre is 43500sf.
My conclusion is that the common wisdom is wrong for dense, Net Zero development, that the streets should run north-south.
A Net-Zero house has most of the windows on the south side of the house because south facing windows can be effectively shaded from summertime overheating, and can harvest wintertime solar energy.
Because all the windows are on the south walls, we can’t have another 2-story house immediately to the south as shown in ‘East-West 3700’ below, or the valuable direct wintertime sunlight will be prevented from entering & you’ll have a house that is gloomy all winter.
Sure, if the lots are big, we can keep the southern house away, as shown in ‘East-West 4500’ below, but then we end up with less than 10 du/ acre (du/a) and there’s no bus & everyone’s driving cars.
The ‘North-South 3800’ drawing below shows a 1-story neighbor garage to the south, avoiding shade. Bingo! That’s a 3800sf lot, and offers 11.34 du/a. Additionally the frontage length is reduced which lowers roadway & utility development costs.
(*1) Transit modes related to residential density (Boris Pushkarev & Jeffry M Zupan)
Plans-for-Sale Powerhouse Designs Website is Now LIVE
Written by: Senna Scott
You asked and we listened!
We are so excited to announce that our Plans for Sale website in now officially LIVE!
Our Design team, Powerhouse Designs, have been working tirelessly at rendering our old & new plans, and working out the bugs back end to make a smooth purchasing experience!
Know of anyone looking to build a net-zero energy home? They can now skip the design phase by purchasing one of our plan-sets and get to building! Saving them thousands on design and getting to shovel-ready even quicker! If local to Bellingham, TC Legend Homes has availability for 2024 – 2025 home builds!
Powerhouse Designs now offers consultation and design services on purchased plans, helping you to customize the plans for your needs! Consultation slots are purchasable on the website.
In addition, Powerhouse Designs now offers NEW SERVICES!
Embodied Carbon Calculations
Built Green Certification Consultation
Net-Zero Design Consultation
Are you looking to calculate your carbon footprint or apply for a certification? Are you a contractor that needs to outsource this work for your clients or need support on making your plans more green? Our staff at Powerhouse Designs now offers Embodied Carbon Calculation Consultations, Built Green Certification and Net-Zero Design Consultation services!
Obtaining Built Green certifications and implementing Embodied Carbon calculations have become a rapidly changing part of the industry. Our team has been up-to-speed and pioneering this process! They will walk you step by step through the process for a stress-free experience!
This just in and hot off the press – the House in the Hollow Case Study! TC Legend built this net-zero house through the winter of 2020/ 2021.
The house-in-a-hollow isn’t really in a hollow, it’s on a knoll, above protected wetlands, northeast of Bellingham. The hollow is formed by the trees, which were preserved to shield the house from overheating, and to conserve the flora of the native wetlands.
Measuring 1950 square feet, this Department-of-Energy certified Net Zero clerestory design has a central kitchen and a 1st floor aging-in-place floorplan. Designed for an Alaskan couple whose love of the outdoors demanded a house that fully engaged with the landscape, plenty of daylight is admitted & access to outdoor living is easy.
“Builder TC Legend Homes of Bellingham, Washington, aims for quality and sustainability in every home it constructs and company founder Ted Clifton Jr. has found the U.S. Department of Energy’s Zero Energy Ready Home program is an ideal way to achieve that goal.”
“The DOE Zero Energy Ready Home program is a great benchmark not only for ourselves, but for all those looking to build or purchase a home that is eco-friendly. Since the program incorporates ENERGY STAR and Indoor airPLUS, holds high standards for energy efficiency, and is nationwide, it is an easy way to compare homes across the board and that reduces confusion for purchasers,” said Clifton.
“It’s also great that the DOE program has a very low cost barrier. There are many other certification programs that charge large fees, making it difficult for small builders to participate. Or, the cost of the fees gets passed along in higher home prices, increasing the barrier to purchase for many people,” Clifton added.
Since 2015, TC Legend Homes has built all of its homes to the DOE program criteria. The builder typically constructs one spec home and five or six custom homes for buyers each year and currently has nine homes under construction. In 2022, the builder was recognized by DOE for its efforts with a Housing Innovation Grand Award in the category “Custom for Buyer under 2,500 ft2.”
Modeled Performance Data of House in the Hollow:
• HERS INDEX: without PV: 33 with PV: -23
• Annual Energy Costs: without PV: $600; with PV: $-280
• Annual Energy Cost Savings: without PV: $1,200; with PV: $2,150
• Annual Energy Savings: without PV: 8,400 kWh; with PV: 20,350 kWh
• Savings in the First 30 Years: without PV: $48,930; with PV: $86,550
Thanks to all who came out to the Zero-Energy Home tours!
And a BIG thank you to Sustainable Connections for co-hosting! We had a great turn out both nights educating the community about what a Zero-Energy home is all about, and how it differentiates from conventional home building.
Learn more about the embodied carbon and the utilities (calculated by Talia & Nicole) saved by this Zero-Energy House in this case study!