Energy Management Applications Any Organization Can Afford

September 20th, 2012
Ashley Halligan, an analyst at Software Advice, recently shared another article with Deltec demonstrating energy management and environmental performance applications that any organization can implement and afford.
With increased emphasis in building performance and higher expectations for lowering consumption and demonstrating a commitment to higher performance, energy management technologies are becoming more and more popular. Furthermore, with new state laws requiring buildings to benchmark and report their ENERGY STAR scores, more operators and managers are being forced to take a look at their overall performance–and address inefficiencies in their operations.
Halligan’s article outlines three applications that do three entirely different things that can help your organization benchmark performance—and at very reasonable (or free) prices: (ENERGY STAR benchmarking), HVAC ASHRAE 62.1-2010 (measures air quality and minimum ventilation rates) and ecoInsight Mobile Audit for iPad (performs energy audits).Read the remainder of Halligan’s article here. has powerful analytical tools to identify ways to save energy, as well as tools to help you complete Energy Star Benchmarking on your buildings

A Book for All Times

September 3rd, 2012

Orson Squire Fowler  (1809 – 1887) is a name which is seldom recognized today. Fowler popularized the ‘octagon house’ movement in America. In his book “The Octagon House: A Home For All”, published in 1848, he praised the advantages of octagonal homes over rectangular or square. Fowler believed octagon structures were less expensive to build, permitted additional living area by using every inch of space, received more natural light through their large windows, were easier to heat, and remained cooler in the summer. A spiral staircase in the center of the house led to the floors above. In the winter this would allow the heat from wood or coal burning stoves to rise, thus heating the upper floors. In the summer, the windows that surrounded almost the entire structure were opened to provide a breeze that would be circulated throughout the house via the stairwell as well.

Cover of "The Octagon House: A Home for All," and the author, Orson Squire Fowler

Cover of the book "The Octagon House: A Home for All," and author Orson Squire Fowler

Fowler made his mark on American architecture. The idea of octagon-shaped houses swept the nation, and his book went through nine printings. Hundreds of octagonal houses were built from the 1850s in New York, New England, Wisconsin, and elsewhere, until the onset of the Civil War. About 2,000 octagonal house still stand today, with the most notable now museums open to the public.

Hardly surprising for such an independent thinker, Fowler was a forward thinking in more than just architecture: he proposed equality for women at a time when women had virtually no legal rights in the United States as well as children’s rights when child labor was considered quite acceptable in the fast-growing industrial world; he proposed ideas on how to discover the ideal mate, on marriage counseling, sex education and hydropathy. He also condemned the use of tobacco by men and tight corsets for women. He was also author of one of the more notorious sex manuals in Victorian times!

Back to the book: We like how Fowler suggested some general structural principles, and encouraged readers to invent the house details for themselves (somewhat similar to adapting a Deltec floorplan and making it your own!) Only a few home examples are offered, and apart from plans, the book has only two illustrations to show how an octagonal house might look. Fowler’s design foresaw a flat roof to collect rainwater, with built-in cisterns to collect and distribute the water (especially interesting in light of today’s sustainability movement), rainwater filtering using filter beds made up of alternating layers of sand and activated charcoal; central heating by distributing hot air from a furnace in the basement; flues, air ducts and speaking tubes built into the thickness of walls.

For Fowler, “beauty and utility were inseparable” (thus anticipating the famous “form follows function” of the designers of the Bauhaus movement in Germany and the United States in the twentieth century by quite a few years). The idea of octagon-shaped houses caught on at once, and his book went through nine printings. Fowler’s “monumental” four-story, 60 room house built during 1848–1853, Fowler’s Folly in Fishkill, New York, contributed to this nation-wide fad. Hundreds of octagonal houses were built from the 1850s in New York, New England, Wisconsin, and elsewhere, until the onset of the Civil War. About 2,000 octagonal house still stand today, with the most notable now museums open to the public.

Fowler was a man of universal reform who preached for education, temperance, and equality—a true a nineteenth century individualist in the Victorian age of orthodoxy, piety, and conformity. Dover republished the book in 1973, 125 years after its original printing, and included many black-and-white photographs of historic octagon homes.


Deltec Builds…Community

August 16th, 2012

Deltec Homes’ staff has kept busy over the summer with community projects. In July, we paired up with community partners Wild South to serve beer at the renown Bele Chere street fest in Asheville, North Carolina. The day was hot, the beers were icy, the customers were happy, and the DJ’s music next door was loud and great for dancing. Proceeds went to Wild South.

Team Deltec Volunteers for Wild South at Bele Chere

Team Deltec volunteers help community partner Wild South at Bele Chere, Asheville's biggest street fair.

In August, Deltec Green Building Coordinator and occasional blog-post author Leigha Dickens, and Deltec sales consultant Dallam Hart swam in a 2-mile long open water swim race for fun and for charity. This was their second year competing in the 4th annual Douglas Lake Swim-A-Thon, with proceeds from the event going to a local food pantry and children’s support center. Dallam took third place in the men’s individual standings. Both swimmers improved their overall performance, compared to last year.

Deltec staff members Leigha and Dallam swim for good

Deltec staff members Leigha and Dallam swim for a cause.

Go, Team Deltec!

Recommended reading: “Breaking Down Net Zero Building: Reality or Wishful Thinking?”

June 26th, 2012

We are pleased to share a summary of a recently published article by Ashley Halligan, analyst at Software Advice, entitled Breaking Down Net Zero Building: Reality or Wishful Thinking?—outlining the true stipulations of “net zero”, as well as considerations on the undertaking of a net zero project.

Halligan begins with the premise that it is essential to understand that net zero indicates that over the course of a year, a building has generated as much energy as it’s consumed.

The article goes on to provide an example of an existing facility—a 363,000 square foot distribution center for the food conglomerate McCormick—that underwent a sustainability initiative that ultimately resulted in not only zero energy consumption, but also ended the 12-month benchmarking period with a surplus.

Next, Halligan discusses tips from experts (including Brian Anderson, Founding Partner of Anderson Porter Design, Dru B. Crawley, former Commercial Buildings Team Lead for the Department of Energy and current Director of Building Performance at Bentley Systems, and Blake Bisson, VP of Sales & Marketing at Ekotrope) for those considering creating a from-scratch net zero building or project.

Halligan wraps up the article with Crawley’s thoughts on whether net zero is truly obtainable on a wide-scale.

We encourage you to read Halligan’s original article here.

Core Green Design Part 5: Efficient Heating and Cooling Design

June 11th, 2012

Heating and cooling is the largest energy expenditure of the average home, so it makes sense to reduce energy bills by getting efficient equipment to do that heating and cooling for you—especially when you’re building a “Pretty Good Home” that incorporates passive solar design and super insulation.

When building such a home in the southeastern US, you can’t get more efficient than an air (or ground) -source heat pump for heating your home efficiently, and affordably. And if you’re going to have a heat pump, odds are you are going to have cooling too, because it’s hot out, and an air conditioner is just a heat pump running in reverse. (There’s some simple physics behind why air source heat pumps are so efficient a choice in mild climates.)  A high efficiency heat pump and air conditioning isn’t the only energy efficient choice in this climate and it isn’t the only green choice either, but as far as cost to install and operating costs are concerned, it becomes one of the most practical choices. An air conditioner is also an important consideration in a climate that is particularly humid—as ours often is—because the process of cooling air with an air conditioner also dehumidifies it, keeping excess moisture from building up in the house to damage interior materials and making the occupants much more comfortable.

There are three ingredients to an efficient heating and cooling system worthy of the performance of a “Pretty Good House” and only the first ingredient is the efficiency of the unit itself.  Toward that end; however, look for a heat pump with a heating season efficiency of 9.0 HSPF or greater, and a cooling season efficiency of 16 SEER or greater.  There will be a premium to be paid for units that are quite this efficient compared to the base efficiencies available, but considering that this system will last a decade or two, the ongoing efficiency is worth it.

The second ingredient is getting a system that is properly matched to your home design.  There is a lot of physics involved in the heat flow of your home, and things like how much insulation, what type of windows, what direction your windows are facing, matter a great deal, especially when you’ve built a home that has more efficient windows and more insulation than average. Heat pumps and air conditioners are typically sized in “tons,” a measure of the amount of heat or cool they can produce, and homes are given a system with a certain number of tons of capacity based on how much heat and cool the HVAC installer determines that they’ll need. A larger home will require more tons than a smaller home, and a well insulated home will require fewer tons than a same-sized home that does not have as much insulation. Getting the precise amount of tons that you need right, without overdoing it, is important since installing a 3 ton system costs more than installing a 2 ton system or even a 2.5 ton system.  An over-sized system uses more energy than is needed to get the home to the desired temperature, and can also be uncomfortable. Air conditioners that are overpowered for their homes will turn on, bring the house to temperature quickly, and turn off again, waiting for the house to warm up substantially before turning on very briefly once again.  This short amount of run time doesn’t give the air conditioner enough time to properly dehumidify the air, as well as cool it, making the occupants continue to feel warm even though the air has been cooled.

The solution is to make sure the equipment has been sized to match the needs of the home by asking your contractor to perform what is called  Manual J calculation, which looks at the actual home design to calculate how much heating and cooling energy the home actually needs. Any HVAC contractor should be able to do one if asked to, but may not automatically do one otherwise—and just because a Manual J calculation is done doesn’t mean that the energy efficiency of the home has been fully considered, especially if the heating and cooling contractor doesn’t know much about what’s going on in the rest of the house. It can also be a good idea to enlist a third party energy professional to the cause, and look to get your home certified under a program such as Energy Star for Homes.  Under most green programs, heating and cooling system design must be highly scrutinized to ensure the energy efficient features of the home are taken into account, and that the system is not over-sized.

The third ingredient is the way that the heated and cooled air is distributed, typically through air ducts connecting to all the rooms in the house.  This duct-work is often run through an attic, crawlspace, or basement—and may or may not be installed in a way that is airtight and avoids being overly restrictive of airflow. You could have the most energy efficient heat pump in the world—but if it’s forcing air into your house through ducts that leak half of their content into your crawlspace and tie themselves in knots on the way to your living room, that energy efficient heat pump will have to operate way more than it needs to in order for you to actually feel warm air.

This, again, is where a third party certification program such as Energy Star can help out, as these programs also often involve visual inspection and testing of duct-work by an energy professional.

Really, as far as heating and cooling goes, even those who don’t want to certify (and remember, the idea behind a “Pretty Good House” is to build green without following the dictates of a certification) do receive an important quality assurance benefit from hiring a third party professional. Oversight on Manual J calculations and duct-work installation are two common green building certification program requirements that can make a big difference in how the home performs.

Hurricane Bud Heralds Early Start of 2012 Hurricane Season

May 24th, 2012

Hot on the heels of Tropical Storm Alberto, Hurricane Bud confirms an early start to the 2012 hurricane season, which does not officially start until June 1. Effectively, we are already in a weather pattern similar to the middle of June.

As the hurricane season takes off, it’s important to stay informed. Stay up-to-date with’s Hurricane Center, and follow the storm in real-time with their interactive hurricane tracker.

The National Hurricane Center (NHC) also offers updated weather information and a checklist for assembling a disaster supply kit, useful whether you will need to evacuate or stay safely tucked in your home. The NHS reminds us that a hurricane watch is typically issued 48 hours before the anticipated first occurrence of tropical-storm-force winds…conditions that make outside preparations difficult or dangerous.

This makes it all the more urgent to hurricane-proof your home as much as possible ahead of time, before a storm strikes. Here are storm-proofing guidelines from Joseph Schlenk, Fortified Home Expert, Deltec Homes, a builder of prefabricated homes with a long history of hurricane resistance.

Trees Trim out dead wood and limbs that could scrape or fall on the house.

Roof Install additional braces in the trusses. A qualified builder can install galvanized metal hurricane straps to secure the roof to the walls. Wait until after hurricane season to replace old roofs.

Gutters Make sure gutters are clean, functioning properly and water from downspouts does not pool near the house.

Pool Lower the water level by a foot or two. Stock up on chemicals to shock the pool after the storm.

Screens Secure or remove screen doors. Remove items that could be blown through screens.

Patio Remove furniture, flower pots, grills, firewood, etc. to a secure place. Patio furniture can be stored in the pool.

Doors Install beefier hinges to make outside doors stronger. Reinforce garage doors by bracing each panel, adding stronger supports and heavier hinges.

Windows Options include hurricane shutters, plywood covers or clear plastic window film. Shutters are effective but relatively expensive. Plywood covers are a good DIY option. Purchase, cut and label plywood covers ahead of time, and install before the wind strengthens. Adhesive window film helps prevent glass from shattering only if anchored in the window frame.

Valuables Move valuable rugs, furniture, pictures, books, etc. away from windows. Store where they are least likely to suffer water damage. Lock important papers and jewelry in the dishwasher.

Supplies Stock up on gas or charcoal for the grill, lights that are gas- or battery-powered and extra ice chests. If you plan on purchasing a generator, do so before the last-minute rush.

Insurance Go over your insurance coverage, including flood insurance, with your agent. Get recommendations from your agent or check online for disaster-relief contractors and have the names and contact numbers of a couple handy — just in case.

Deltec Homes is known for building hurricane force wind resistant round homes worldwide since 1968. Read Deltec homeowner hurricane survival stories here.

Core Green Design Part 4: “Right-Size” the Home and Incorporate Livable Outdoor Space

May 17th, 2012

Sarah Susanka’s book, “The Not so Big House,” started a movement in green home design, a reaction of conscience to the gradual rise in home size that had been going on since the 1970s, as populations shifted away from the cities into the suburbs. From the US Census we know that median home size grew from 1600 square feet of home in 1975 to just over 2200 square feet of home in 2005, just before the 2008 recession—a 35% increase. Yet home size is a trend that has begun to reverse itself in recent years, as more and more homeowners realize that the “American dream” has to do with quality as well as quantity, that the downside of a large home is larger maintenance, cleaning, and energy expenditures.

The “green” benefits of a home that has been “right-sized” to match the true needs of a homeowner’s lifestyle are many. Less square footage costs less overall to build, and savings on size could be put towards those “above and beyond” green features that an eco-conscious homeowner has always dreamed of. Less square footage also reduces the amount of disturbed land, reduces the amount of materials used—and certainly reduces energy bills.

The true size needs of a home differ, depending on the number of people who expect to live there and other expected uses of the home, so there is no one, “this size home is green, but this size home is not” limit.  However, “right-sized” homes tend to trend away from some of the things we saw in homes designed in earlier decades: forgoing extra, formal dining rooms, living rooms, winding caverns of practically-empty basements, and featuring smaller and simpler master suites. Avoiding hallways, and allowing foyer or entry spaces to double as reading nooks or other useful spaces, are also common practices. An overabundance of clutter can make a space feel smaller than in actually is, so having adequate space set aside for storage can also be a helpful strategy. In addition, considerations like future handicap access and other “age-in-place” concerns may also enter into a home right-sizing design.

Livable Outdoor Space

The nice thing about living in a mixed climate is that although we can experience both very hot and very cold temperature swings, there’s a large portion of the time when it’s quite nice outside. Where I grew up, in muggy upstate South Carolina, our screened-in porch off of the shaded north side was my favorite “room” in the house.  In fall, spring, and even summer evenings, it often served as a dining room, sitting room, and occasionally, a bedroom, offering this nature-loving child an opportunity to spend the night “outside” listening to the tree frogs and crickets sing into the night. One of the unexpected aspects of dorm life that chafed me the most was the simple lack of any kind of porch space. Having access to outdoor living space is a quality-of-life concern, as much as a green concern: the opportunity to experience the outdoors in your own home is, to many of us, nourishment for the soul—often under-appreciated when we have it but very conspicuous when it’s absent.

This Deltec home incorporates porches and decks to add livable space to the home. Although not conditioned, these spaces can be used for dining, entertainment, relaxation and recreation during pleasant weather.

Incorporating outdoor living space is one of my favorite strategies in a right-sizing home design in this climate, as outdoor rooms can make a floor plan feel larger, more versatile, and more like home.

Core Green Design Part 3: “Super”-Insulation

May 10th, 2012

You can’t talk green building without talking about insulation: it plays a critical function in energy efficient design. Insulation acts like a blanket or wool sweater for a house: it slows down the gradual loss of heat through conduction, thus allowing you to enjoy the warm house you used all those fossil fuels to create for longer, before more fossil fuel input is required to bring up the temperature once again. In the summer, insulation helps keep heat out of your home.

How Much Insulation?

Just like putting on a thicker coat keeps you warmer than a thinner one, more (properly installed) insulation has greater energy efficiency than less insulation—so the answer to the question “how much insulation is enough” is something of a moving target. In the olden days, homes were often built without installing any insulation at all. In the past two decades, however, most state building codes began requiring a certain amount of insulation in the walls, ceiling or attic, and floor. In the past decade, the codes have become stricter and stricter, requiring more and more insulation.

The goal of an exceptionally green house—what we’ve dubbed a “Pretty Good House” in our conversation—should be to exceed code requirements. That’s the “super” in “super-insulation.” The trick is to arrive at an insulation balance somewhere between “more is always better” and common sense, based on the goal of the home: to have much lower energy bills than standard new construction, perhaps as much as 2/3s lower. In Green Building Advisor’s original conversation on the “Pretty Good House” the “R10-R20-R40-R60” rule was posited as best for cold climates. (More R-value means more insulation.)

This rule means going with R10 insulation values underneath slab foundations, (building code often requires none), R20 insulation values in foundation walls (building code requires R10-R15), R40 in exterior walls (building code requires R13 to R20, depending on your climate, with R13 being the maximum R-value you can get with batt of that “pink stuff” installed in a 2×4 wall), and R60 in the attic (building code requires R38 in most “mixed” climates).

In mixed-humid climates, experience has shown me that values can be relaxed some, and I propose that a “10-15-30-50” rule is a good starting point: a minimum value that can be achieved at a relatively good cost payback. If budget and space permits, higher values in exterior walls would still make good sense. Innovations like a double stud wall or a raised heel truss help increase the amount of space one has in which to fit all of this extra insulation.

The Solar Homestead, Appalachian State University’s 2011 entry into the US Solar Decathlon, used super-insulated walls as a strategy to help the home reach “net-zero” performance cost-effectively. (“Net-zero” means consuming very little energy and producing what energy is needed with on-site renewable energy for a “net” energy bill of zero.) Home is built with double 2×4 walls allowing 8″ of space for insulation, double the amount of space allowed for wall insulation in typical construction. While a “Pretty Good Home” is not necessarily aiming to be a “net-zero” home, super-insulation is still a core green design strategy.

Insulation Alone is Not Enough

Most insulation products are only as good as the wall or ceiling in which they are installed—and are designed to be installed uncompressed, evenly, and often in an enclosure that is air-tight. Cramming an R19 batt into space for an R13 batt does not equal R19 walls, and a pile of loose-fill cellulose insulation in your attic does nothing to stop heat loss from any sections that are uncovered. Paying attention to the proper installation for each type of insulation product is absolutely crucial.

Another aspect of the building envelope that is often forgotten in the quest for maximum R-values is the total air-tightness of the home—as warm air leaking out and cold air leaking in are an entirely different source of indoor temperature change that must be corrected with a heating or cooling system. Pretty Good Houses should be exceptionally air-tight, with any and all cracks and penetrations in the exterior of the building sealed. Yes, this kind of detail work takes extra time and attention, but is just as important, if not more so, than the R-values you choose to put into your super-insulation.

Next up in our southeastern climate “Core Green Design” series: “Right-sized” Homes and Outdoor Living Spaces

Core Green Design Part 2: Passive Solar

April 18th, 2012

Last month I wrote about the concept of the “Pretty Good House”–a home that exemplifies the most fundamental green building features that make sense with the local climate without necessarily going through the process of pursuing a green building certification. And when building in the southeastern climate, where Deltec Homes is headquartered, I created a list of the features that I recommend as the most important “core” green strategies, strategies I think are integral to building a “Pretty Green House”:

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

I put passive solar design at the top of this list because it is such a simple, easy design principle, capable of reducing energy costs while also being decidedly low-tech. If you’re unfamiliar with passive solar design, the Southface Institute has a great primer in it’s online library. The basic concept beside passive solar design is to use your home orientation, window layout, and overhang sides to harness heating energy from the sun in winter, while keeping that extra heat out of your home in the summer.

A passive solar Deltec in North Carolina uses south-facing windows and deep overhangs to harness heat in winter while shading windows in summer.

And in a climate like Western North Carolina, keeping heat out is the rub.

As a practice generally conceived of in more northern climes, some of the well-known passive strategies for allowing heat in can become a double-edged sword when you are building somewhere that has a significant cooling season. Here are some basic passive solar ingredients in a Passive Solar “Pretty Good Home,” fined-tuned to match the challenges of building in a mixed-humid climate:

1.  Do Have South Facing Windows–But Don’t Overdo It

Many folks understand “passive solar” as a strategy that entails putting a whole lot of glass on the south side of the home. Well-designed overhangs will shade these windows in the summer when the sun is higher, while leaving them un-shaded in winter. South-facing glass is indeed the essential ingredient in a functional, direct-gain passive solar design—but too much glass on the south side can turn a comfortable space into a stuffy oven in fall or spring, or even on a warm afternoon in winter. As a general rule of thumb, south-facing window areas that exceed 7% of your conditioned floor area can start to introduce overheating problems at some point during the year in this climate–unless you start to incorporate thermal mass.

2. Don’t Skip the Thermal Mass

Thermal mass is a dense material in the directly sunlit area that can store the heat that south-facing windows are letting into your home–material such as a concrete slab or tile floor. Often referred to as a “thermal battery”, thermal mass is as critical to effective passive solar design as are south-facing windows, because without it you lose the ability to hang on to a large portion of the heat that your south-facing windows gather.

Home designs that do not have adequate thermal mass planned should be very wary of over-doing their south-facing windows.

3. Avoid East, and Especially West, Facing Windows

No matter what time of year it is, the sun will be low when it rises in the morning and sets in the evening. That low angle sun won’t be shaded by overhangs designed to keep the south-facing windows shaded, and can present an especially uncomfortable situation on spring and summer afternoons in rooms that have west-facing windows. While unwanted heat from low-angle sun makes limiting east and west facing windows a good idea in any climate, in a mixed-humid climate, east and west windows might be best eliminated all-together.

4. Insulation!

South-facing windows paired with good overhangs bring in extra heat at appropriate times, while thermal mass stores that heat in the dense building components of your home. Good insulation serves to slow the eventual process of heat leaving your home, and the more you have of it, the longer you can hold on to that heat. Taking insulation levels above and beyond what code requires, often referred to as “super-insulation”, will be the subject of the next post in this series.

Deltec Participates in White House Round Table on Sustainable Manufacturing

April 3rd, 2012

Deltec was honored to participate recently in a White House and EPA sponsored event on sustainable manufacturing. The round table discussion was invitation-only, and was facilitated by Jim Jones, Acting Assistant Administrator of the Environmental Protection Agency.

The group of regional manufacturers discussed best practices and current challenges in achieving waste and energy savings at all levels of operations. Participants had the opportunity to speak directly about issues affecting North Carolina’s manufacturing base, and discuss ways they could partner to help improve and expand American manufacturing, including sustainable manufacturing, lean manufacturing and the opportunities for green products.

round table discussion on Strengthening Sustainable Manufacturing in North Carolinas
Participants at the invitation-only round table discussion organized by The White House, the EPA and Waste Reduction Partners