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While I love the Mandala Homes designs (and their proximity to me in BC), the Solar Farmhouse from Deltec Homes runs a close second and would likely be my top choice for an eco-friendly prefabricated family home if I lived anywhere near North Carolina.
Deltec Homes are arguably one of the greenest prefabricated building companies around. Their manufacturing process produces no hazardous wastes, they build incredibly energy efficient eco-friendly homes, and their factory has been powered by 100% renewable site electricity since 2007!
What makes them green?
Deltec Homes produce an annual Sustainability Report packed with interesting information about their practices and goals for being even more eco-friendly.
In addition to having a prefab factory powered by photovoltaics and renewable wind energy, Deltec Homes have established a comprehensive re-use, donation, and recycling system that enables them to divert more than 80% of manufacturing waste by volume from landfill. To achieve this, they do things like use small pieces of leftover foam board to insulate the structural header of the Energy Wall system, increasing the energy efficiency of your home without extra costs and while reducing construction waste.
Deltec also partner with Appalachian Offsets, a non-profit organization based, like Deltec, in North Carolina, to offset carbon emissions from domestic shipping. These offsets are helping to fund a solar array project at a local elementary school. In 2018, Deltec offset 84,000 domestic shipping miles through this partnership.
Further demonstrating their eco-friendly credentials, Deltec are careful to source building materials from suppliers with a track record of sustainable practice. For instance, their exclusive supplier of truss lumber, Beadles Lumber (now owned by Canfor Southern Pine), has achieved the Sustainable Forestry Initiative® (SFI) Certified Sourcing certification. Deltec also source SFI Certified plywood from Georgia Pacific, which is used in wall, roof and floor sheathing, and Huber Advantech, for floor sheathing used in their Ridgeline and Solar Farmhouse models.
The metal shingle roofing offered as an upgrade on Deltec’s round home designs is an Energy Star Certified cool roof product, containing 90% recycled content. The shingle shape allows for reduced waste compared to sheet metal. Windows are also mostly Energy Star Certified and entirely sourced from Marvin Integrity, a 100% U.S.-made and woman-owned company, with high efficiency Tripane available for cold climate and high energy performance projects.
The Deltec Solar Farmhouse features a sustainable siding choice: Boral TrueExterior™ polyash siding, which is Cradle to Cradle Certified™ Bronze and contains a minimum of 70% recycled content. Cradle to Cradle Certified™ products are evaluated for material health, material re-utilization, renewable energy use and carbon management, water stewardship, and social fairness.
Unsurprisingly, then, Deltec have built Energy Star Certified homes, a Green Built North Carolina home, and even a DOE Zero Energy Ready Home, which requires using advanced green building practices in energy efficiency, air quality, durability, water efficiency, and solar-ready design.
Zero Energy Ready Homes must also meet EPA Indoor Air Plus Certification, requiring mechanical fresh air ventilation, passive radon mitigation, higher levels of filtration, ultra-low emitting paints, stains, carpet and wood products, and safe and clean burning combustion appliances. It also requires that steps be taken to reduce pollutants during construction such as covering all registers and flushing out the home prior to occupancy. The Zero Energy Ready Certified home built by Deltec in 2018 included a 6.8 kilowatt grid-tied solar array, sized to meet the home’s electricity needs with a net energy bill of 0 and a HERS score of 0.
Deltec actively encourage their clients to pursue a green building certification and help guide you through this process. In 2018, 58 % of Deltec homes shipped exceeded the 2009 international energy conservation code by 20% or more; 24% exceeded 2015 IECC by 20%.
What else is great about Deltec Homes?
Deltec Homes has a building scientist and HERS Rater on staff who offers free consultation on green building strategies for clients. That means you can nerd out to your heart’s content about insulation strategies, HVAC systems, indoor air quality best practices, passive solar design, projected energy use modeling for a proposed home design, green building certification planning, material sustainability and more.
Deltec also offer green home building seminars, which are well attended and a great place to meet likeminded folks looking to build an eco-friendly prefabricated home.
Deltec offer a range of services through their green building department, including:
- Evaluation of insulation types and specify above-code R-values
- Evaluation of HVAC system types and options, ensure proper HVAC design
- Development of a durability plan with you and your builder
- Assisting with building certification programs such as ENERGY STAR, LEED and the NAHB National Green Building Standard
- Passive solar design review including overhang sizing and shading analysis, window location and thermal mass
- Planning and integrating renewable energy systems
- Researching sustainable products and finishings such as insulation, flooring and low-flow plumbing fixtures
- Working with your builder on air-tightness details during construction
Deltec’s in-house construction expert is available 24 hours a day to answer questions and they offer an on-site technical assistant, should you need one to make sure your build goes smoothly.
What kind of eco-friendly prefab homes do they build?
Deltec provides the structural shell of your new home, which includes:
• 2″ x 6″ x 8′ wall panels with pre-installed 5/8″ plywood sheathing and TYPAR Drainable Wrap
• Double 2″ x 10″ headers in all wall panels
• Pre-cut 5/8″ plywood roof sheathing with UDL Titanium Underlayment
• Complete half-scissor truss roof system with steel ring and collar
• 1′-9″ overhang
• WebTec floor system, if building on a basement, crawlspace, or pilings
• Connection hardware
• Custom floor plan
You can add in pre-installed, pre-painted siding, pre-installed windows, deck systems, skylights, wing and connect additions, covered porch kits, garages and a whole host of other options, plus renewable energy systems, ERV, and more.
Deltec Homes’ Classic round home model has a self-supporting roof system that allows you to create any floorplan you like and to take advantage of panoramic views from your lot. This round shape is hurricane resistant and offers 10 shapes and sizes, with wing options. Depending on your design, you home could be impressively energy efficient or super energy efficient, reaching net-zero level and beyond.
The Classic 2-bedroom, 2-bathroom, 2,075 sq. ft. model starts at $129,000 for the shell package, on top of which you’d need to factor in costs for permits, site preparation, labor, finishes, fixtures, appliances, inspections, and so forth. The company offers a 7% Military discount in the U.S.
The turnkey price for a Deltec home is around $200-$275 per sq. ft. Compared to a conventionally built house that just meets standard building codes, a Deltec home offers cost savings over the lifetime of the home, thanks to energy efficiencies and low-maintenance, durable construction. These homes are also superior in terms of indoor air quality and healthy living.
Deltec Homes Classic round home series includes small prefab homes providing 300-1,000 sq. ft. of space, homes with 1,100-2,400 sq. ft. of space (their most popular size), and larger homes with 2,500 sq. ft. of space and beyond. Their wing and connect options mean you can easily build a grand home with over 10,000 sq. ft. of space, which is great if you’re, say, running an eco-retreat.
The Renew Collection is Deltec’s line of more conventionally shaped homes that are high-performance and net-zero. Most models have two floorplan options and these homes are designed to use two-thirds less energy than a typical home, with the other third drawn from renewable sources.
The Deltec Balsam model is a great option for a modern version of a mountain cabin. It has a passive solar design, air-tight structure, and an open floor plan. The Ridgeline model also has a passive solar layout and offers six designs ranging from small to larger footprints. The Ridgeline model was used to design the DOE Zero Energy Ready home built by Deltec in 2018. This design boasts vaulted ceilings, clerestory windows, side entry porches, and can accommodate solar hot water and PV-energy. A Ridgeline model in turnkey condition will likely cost you between $215,000 and $335,000 for a 3-bedroom, 2-bathroom home.
Personally, I’m a bit smitten with the Solar Farmhouse model, which offers a classic farmhouse without the classic farmhouse drafts, spiders, and gargantuan energy bills. Thanks to Deltec’s design experience, this prefab home has all the modern functionality and energy efficiency you’d expect from a passive solar design and air-tight building envelope.
Who are Deltec Homes and why should you trust them?
Deltec are a certified B Corporation, which is rare in this industry, and are also Living Wage Certified, through the Living Wage program of Just Economics in Western North Carolina, the largest program of its kind in the United States.
Deltec Homes are one of the best options if you live in an area prone to high winds and seismic events. Several Deltec homes were in the path of Hurricanes Michael and Florence in 2018 and they all survived entirely unscathed! That’s because Deltec build durable, prefabricated, eco-friendly homes made of high quality, long-lasting materials. The side benefits of this process include lower energy costs and reduced time and money spent on home maintenance. Various components of Deltec structures have generous warranties, including a 50 year warranty on the material in their fiber cement siding and for their classic metal shingle roof, and a 25 year warranty on paint if it is pre-painted in their facility. You can also work with Deltec to get your home certified by the Fortified Homes program, which could vastly reduce your home insurance costs if you live in a high wind area prone to increasingly strong climate storms.
All products included in the Deltec shell package comply with LEED 2008 VOC emissions standards, CARB II and contain no urea formaldehyde. To further support indoor air quality, Deltec offer ERV or HRV fresh air ventilation systems designed to provide ASHRAE62.2 recommended ventilation levels.
The standard Deltec home designs make it easy to incorporate their optional photovoltaic-based solar hot water system, and the company will help you find a local installer for solar electric systems if you take that route. Their Sun Bandit solar hot water system uses two to four solar electric panels, and a special electric water heater, to provide interrupted water heating from solar with lower ongoing maintenance than the older, solar thermal style systems. This is a complete hot water kit available with the Deltec Homes shell package.
The only downside I can see with Deltec Homes is that they are based so far away from me! Seriously, though, if you are closer to North Carolina and looking for an eco-friendly home with superior energy efficiency, from a company that clearly knows their stuff and cares about the environment and their clients, you should check out Deltec. Your home construction loan may have to be a little higher than anticipated, but you’ll get to live in a beautiful, durable, high-performance home and see serious cost savings the longer you live there.