Core Green Design Part 1: the “Pretty Good Home”

March 18th, 2012

Recently over at Green Building Advisor, a great resource for green building knowledge, there’s been a hot discussion around the concept of building a “Pretty Good House.”

Now at first glance, that sounds like a bad deal. Don’t we want to live in a house that’s more than just “pretty good?” Yet the idea behind a “Pretty Good House” is to provide a new type of roadmap for building a green home, one that focuses on cost-effective and common sense energy and durability performance, rather than trying to build to the exact requirements of a green building certification.

Don’t get me wrong, I think that green building certification programs like LEED or Passive House are wonderful, well-thought out ways to create a building with reduced environmental footprint and lasting value for the homeowner, but they aren’t for everyone. Certification means that a widely-recognized green label gets placed on your home—but it also means extra cost in certification fees, and building to a checklist of requirements that may not have the flexibility to match everyone’s budget or design constraints. By contrast, a “Pretty Good Home” is a home that doesn’t certify but that incorporates those green building and energy efficient features that made sense to the project and were cost-effective, enabling homeowners who don’t have the flexibility or funds to go all the way to a Passive House the opportunity to live in a house that functions well and has a reduced impact on the environment.

Since it isn’t a certification, but rather an idea, green building professionals across the country have been given the opportunity to weigh in on what green strategies define a “Pretty Good Home” in their particular climate. Recently, some of my suggestions for a “Pretty Good Home” in a North Carolina climate–what building scientists often refer to as a “mixed-humid” climate–were featured in a follow-up post at Green Building Advisor. Whether you’re building a home that aims to go all the way to Passive House standards or one that merely aims to have some Pretty Darn Green features, these are the most important green strategies that I recommend to customers building in a climate that is cold in winter, warm in summer, and humid for a good portion of the year.

1. Passive Solar design
2.Insulation values exceeding minimum code requirements
3. A “right-sized” home that incorporates outdoor living space
4. Solid heating and cooling system design
5. Smart water management

In follow-up posts on this blog, I’ll go into each of these design principles in more detail.

Deltec Builds Another Energy Star Home

January 6th, 2012

The Stilwell home in Fairview, North Carolina is a green home–literally, as the exterior features forest green siding and a green metal shingle roof. But the Stilwells have built their beautiful home to be environmentally friendly as well:  featuring passive solar layout, solar-assisted radiant floor heating, earth-based paints and natural interior products sourced from a local dealer, fresh air ventilation, and Energy Star certification.

Energy Star is a certification available to new homes constructed under certain guidelines that intend to make them at least 15% more efficient than a standard new home. The EPA recently released their “Designed to Earn the Energy Star” program for pre-designed homes, and Deltec, which provides floorplans and an energy efficient building shell, has been able to assist customers in certifying their home under this label.

The requirements for an Energy Star certified home are many, but well-installed insulation and air-tight construction are two of the most important. One of the tests a home must pass is a blower door test, which measures how air-tight the entire home is. The more air-tight a house is, the less energy it uses, because it isn’t constantly having to heat or cool air leaking in from the outside. Deltec’s green department videotaped the Stilwell’s blower door test, which was performed by VandeMusser Design.

To achieve the required blower door test score, the Stilwells used spray foam insulation in the ceiling, a material that blocks air movement in addition to providing insulation. Their builder was also very dilligent at applying caulk where the components of the home fit together. We’re pleased to report that the home passed with flying colors!

The Stilwells have a blog of their own where they’ve shared their experiences in constructing a very green Deltec home. Bloomberg Television’s host, Lee Patrick Sullivan, recently visited the Stilwell’s and interviewed them for the program EnergyNow, for an episode covering energy-efficient home building methods. On the same day, Sullivan toured the Deltec Homes plant in Asheville, North Carolina, and visited two other owners of  Deltec homes. The program is scheduled to air Saturday, January 7 at 5:30pm, and Sunday, January 8 at 9am and 1:30pm.

Deltec Employees Tackle Home Energy Efficiency: Part 2

December 12th, 2011

Building a new home to be extremely energy efficient undoubtedly saves money on the ongoing operation of the house. Wouldn’t it be nice if all homes had been built to the same energy efficiency standards as new homes are today? Even if you live in an older house, however, there are steps you can take to make it more energy efficient.

Deltec recently began offering its employees a ‘weatherization program’, whereby participating employees spend less than $100 on materials and a few hours of elbow grease at each others houses to tackle common energy efficiency shortfalls in existing homes.

A few months ago we worked on the engineering director’s house, sealing up leaky spots in his semi-finished basement and tightening up his home’s duct-work. This time around, it was the sales director whose home we put in the spotlight.

Our work began with inspecting underneath the registers, those vents in the floor that allow the heated/cooled air to circulate in your home. Often the ends of air ducts don’t fit perfectly within the hole cut for the register, allowing some of the air meant to heat or cool your home to escape back down into the basement or crawlspace.  Sealing the perimeter of each register boot in your home to the floor can help make sure more of the air you’ve already heated actually makes it into your living space.

Joe using caulk to seal the duct-work in the register to the floor.

Materials needed: one or two tubes of caulk and a caulk gun

Time required: one hour or less to do the work, plus an hour or two to let caulk dry before replacing register covers

Our next stop was to tackle a particular problem in the attic:  In Joe’s house, as is common in two-story homes with a basement, a long shaft called a chase serves to enclose the duct-work that runs from the furnace in the basement up into the attic and over the second story of the house. This chase is about 4×4 feet in size, large enough to fit several large ducts.  However, as is often the case, in Joe’s house the top of this chase was not capped off, leaving a hole in the floor of the attic. Covering this hole keeps warm air inside the house from escaping into the attic, and creates a surface for attic insulation to rest on so that it doesn’t fall down the hole.

Steve in the attic, using rigid foam insulation to seal off the top of a chase.

Materials needed: rigid foam insulation, measuring tape to measure the hole, something to cut the foam to size, mastic and a brush to seal it in place.

Time required: one hour or less.

We still had some more work to do in the attic. When holes are cut in a ceiling for water pipes, bath fans, or electrical wires, those holes are generally a little bigger than they need to be, thus allowing some air from the home to escape into the attic.  In addition, where the tops of interior walls intersect with the ceiling sheet-rock there is often a small crack where the two materials are not installed completely flush to each other. We dug through the insulation to find as many of these holes and cracks as we could, and sealed them with mastic.

Leigha raking insulation back into place after sealing various small holes in the attic floor.

Materials needed: mastic and a brush, mask, gloves, and a rake

Time required: Two to three hours to dig through insulation, find things to seal, let the material dry and then rake the insulation back into place

When working in an attic with insulation, it’s a good idea to wear a mask and gloves to avoid irritation by fiberglass insulation.  Be sure to watch your step and to stand only on rafters, as a sheet-rock or plaster ceiling cannot support a person’s weight.

This program was a great way for employees to have a little fun while working hard, learn a thing or two about their houses they might not have known, and spend only a little time and money to tackle some “low-hanging fruit” items that can make a big difference in their energy bills this winter.

Appalachian State Wins People’s Choice Award

November 3rd, 2011

Appalachian State University won the U.S. Department of Energy Solar Decathlon 2011 People’s Choice Award for its Solar Homestead, sponsored by Deltec Homes. The award gives the public the opportunity to vote for its favorite net-zero energy home out of a total arena of nineteen homes. Over 92,000 votes were cast, with the ASU team coming out on top.

“The team’s passion and enthusiasm were contagious,” said Terri Jones, Solar Decathlon Communications Contest official. “The People’s Choice Award is a popular vote, and I believe the Solar Homestead house and team appealed to people on many levels.”

The Solar Homestead is a self-sustaining, net zero-energy house inspired by original homesteads established in the Blue Ridge Mountains. The Solar Homestead integrates this concept with a highly energy-efficient home, incorporating renewable resources and innovative technology into a prototype that is adaptable, self-sufficient, rugged, affordable, and attractive.

Appalachian State also won second place in the Communications Contest and third place in the Architecture Contest.

Deltec Homes is honored to have worked with such a dedicated, enthusiastic, and creative team. Their passion kindled a true feeling of excitement at our company, and reminds us all why building sustainably is so important.

Deltec Unveils Net-Zero Home

October 13th, 2011

Building sustainably is about building an energy efficient, resource efficient, and durable home; about reducing your impact on the environment and reducing the ongoing maintenance and energy costs associated with owning a home.  Some of the highest performing homes are now designed to be so energy efficient that they use on-site renewable energy to produce as much energy as they consume.  These homes are called “net-zero” homes because their energy bills is effectively zero, and although they incorporate renewable energy and many other “next-generation” green technologies, many are being built today, all across the country.

Now Deltec is unveiling our own Zero Energy Home design—a home featuring all of the benefits of living in the round that is designed to produce as much energy as it consumes with an on-site solar array.

A net-zero home features more than just solar panels.  The high performance of these homes starts with a well-designed building envelope—and Deltec has always excelled in producing a very energy efficient building shell.  With wall insulation at R40, roof insulation at R60, and high efficiency heating and cooling and electric design, the energy efficiency features of Deltec’s Zero Energy Home cut energy use by 2/3rds.  The remaining third is provided by on-site renewable energy.

More information on the Zero Energy Home will be available on our new website coming soon.  If you have any questions, please give us a call at 800-642-2508.

The Solar Decathlon Zero Energy Homes Exhibition is Underway

September 23rd, 2011

ASU's entry in the 2011 Solar Decathlon

Yesterday we had a wonderful opportunity to get a sneak preview of the 19 zero energy homes at this year’s solar decathlon in Washington DC.  The competition is already underway, and the homes are open today to the public.

Deltec is proud to be a sponsor of Appalachian State’s Solar Homestead. Their project combines the flexibility of the traditional homestead with cutting edge technology.  It showcases an ultra high-performance building envelope built in Deltec’s facility, along with plenty of solar energy and excellent outdoor living spaces.

There is an amazing variety of technology, architecture, and creativity on display here – most definitely an inspiring journey if you are in the area.  Click here to see a video of all the innovative projects we toured.

Deltec Employees Tackle Home Energy Efficiency

September 8th, 2011

When building a new home, it pays off to think about energy efficiency, as many construction details done incorrectly or missed altogether can leave a lasting effect on a home’s energy consumption.   Yet armed with knowledge, some easy-to-come-by materials, and a little elbow grease, an existing home can be made more energy efficient.  Indeed, “weatherizing” a home has become a popular way to save money in the face of rising energy costs.  This fall, a handful of Deltec employees are getting together to tackle easy opportunities to weatherize each others’ homes.

Last Sunday we took on the home of our Director of Engineering, where, even having only one weekend morning to work, we found and corrected two all-too-common energy efficiency shortfalls:

1.  Leaky Band Joist

This basement, like many basements, is built of cinder block walls. The wooden components of the house above;  the floor joints and wall framing, sit directly on top of these concrete walls, often with nothing at all installed between wood and concrete.   This makes for a junction that is far from airtight, and in many places we could see light from outside through the gap between wood and cinder block.  Not only was this gap allowing cold air into the basement in the winter, making downstairs TV watching far more chilly than necessary, it was letting in that cold draft right underneath the floor of the house upstairs.  The homeowner had commented that the floors near outside walls sure were cold in winter!

The area where the wooden floor joists of a house rests on the cinder block walls of the foundation is called the “band joist.” In some cases, we could see daylight through the gap between the wood and the cinder block.

The fix was relatively simple: we sealed the gap between wood and concrete around the entire perimeter of the basement with silicone caulk.

2.  Leaking Air Ducts

Duct-work is designed to bring warmed or cooled air from your mechanical unit and into the living spaces of your home.  You would think duct-work would be extremely air-tight, the better to deliver as much warmth or coldness as it can.  In reality, most duct-work is anything but airtight, leaking as much as 25%–one quarter–of the air it carries.  Most of these leaks occur at joints in the sheet metal that make up ducts.

Sheet metal duct work leaks out a lot of the air it carries. That’s because it is made of multiple segments joined together, with nothing to seal the joints.

In this house, we covered these seams with a special kind of fiberglass tape–NOT duct tape, which loses it’s stickiness throughout several seasons of temperature swings–and painted over the tape with a good thick layer of duct mastic.  Duct mastic comes in a tub at a home improvement store and looks and feels like putty–but dries into a tough but flexible air-tight material.

Stay tuned for more home energy efficiency projects we will do for each other.

Deltec Homes Appears On Planet Green TV

September 1st, 2011

Build Green. Live Green. Deltec Homes builds innovative, sustainable homes that work with nature not against it.  Every prefabricated round home that Deltec custom builds is inherently green, saving not only energy, materials and labor costs but the planet as well.  Deltec is committed to a greener world. In line with this philosophy, Deltec has started a new campaign on Planet Green beginning Monday August 29,2011.  To see a preview of the campaign, watch the video below and look for us on Planet Green TV on your local cable network.

Energy Star Certification Helps Custom Homes Save Energy

July 18th, 2011

Many of us know that Energy Star appliances use less energy than their competition.  But some may not realize that a home itself can be Energy Star certified. An Energy Star certified home will use at least 15% less energy than standard homes but often up to 30% less energy.  The Energy Star label is achieved for a new home through a combination of strict insulation, air tightness, water management, and heating and cooling building practices.

Yet building a home to earn Energy Star requires planning, and collaboration across many of the contractors and disciplines who will be working on your home.  While builders of spec homes can do all of the organizing they need to build an Energy Star certified home, those interested in designing and building their own home face greater challenges in pulling all of those pieces together.

Now the EPA has unveiled a program for architects and panelized custom home designers, like Deltec Homes, called “Designed to Earn the Energy Star.” Home plans that are “Designed to Earn” are reviewed by a third party energy professional for compliance with Energy Star’s lists of requirements.  This enables customers to pin down key construction decisions early in the planning process, avoiding headaches down the road.  After finalizing their Designed to Earn plans, customers can then take the preliminary Energy Star paperwork to an energy professional where they are building, who can perform the field testing required to complete Energy Star certification.

Deltec Homes is proud to be able to offer Design to Earn Energy Star services to interested customers.

Benefits of Energy Star Certification:

  • Ensures an extra level of home performance by prescribing the most energy efficient practices in key building areas such as HVAC and insulation, and then testing the finished home to make sure it lives up to the designed performance.
  • As a nationally respected label, Energy Star certification adds to the recognized total value of the home.

For more information on how Deltec can help you get your home Energy Star certified, call Leigha Dickens, a Deltec Green Building professional at 800.642.2508 or email Leigha at

Leigha Dickens, Deltec Green Building

Deltec Makes the News-Home Sweet Circular Home

June 29th, 2011

RSW Living Magazine, the regional southwest Florida’s lifestyle magazine, does a feature story on Deltec in their July/August 2011 issue. “Looking for a new angle on a custom home? Consider one with no angles at all” states Beth Luberecki, writer for the magazine.   Beth interviewed several Deltec homeowners living in south Florida including one family in Port Charlotte that were thrilled to be living in a Deltec when Hurricane Charley roared through in 2004.  “Our house suffered no damage whatsoever” said the homeowner. Of note, Deltec has over a 40 year track record of never losing a home to hurricane force winds.

While the circular home design doesn’t appeal to everyone, another homeowner interviewed for the article from Venice, Florida is a raving fan of the Deltec round design.  “The roundness feels really good. Am I a lucky girl or what?”

Read the full RSW Living Deltec Article July/August 2011 article.