Comparing Green Building Certification Programs

A few weeks ago, I was asked to speak at the Arlington Chamber of Commerce about green building programs, and so I've spent some time recently thinking about and researching all the different green programs available to us in Northern Virginia. There are four programs that are the most well-known and often-used in Northern Virginia, and Arlington especially. In no particular order, they are:

 

• Home Innovation (formerly NAHB Research Center) NGBS homes
• LEED for Homes
• Earthcraft Va
• Arlington County Green Home Choice Program

 

Energy Star appliances are just one aspect
of Energy Star 3.0 certification.

Over my next few blogs, I'll talk a bit more about each of these programs, so this is just a quick overview to start us off.

 

All four programs rely on the EPA's Energy Star program in some way, shape or form. One ofArlington Designer Homes, all our homes are Energy Star certified, and it is certainly the easiest way to demonstrate that you have met a particular program's energy requirements. But because Energy Star certification is not required for Home Innovations certification, it gives the builder and homeowner more flexibility in using a variety of green features to meet certification requirements. And with all the new green building technologies available to us today, there are so many different ways to make a house more energy efficient!  All of the other programs require Energy Star certification to certify a home at a certain level. (I will talk more about Energy Star 3.0 in my next blog.)

the reasons that I like Home Innovation’s green rating system is that it allows you to certify a house without it being certified Energy Star 3.0. At

 

A solar water heater is another green feature that helps
improve energy efficiency and earn a home's green certification.

There are many more things that unite green certification programs than divide them. All of the programs mentioned above have categories covering different types of green features - you can refer to our blog from May 19^th, 2011, to review basic categories for the Home Innovations certification program (formerly NAHB Research Center). All of the programs rely on Energy Star in

some way. And most importantly, all these programs require strict third party certifications.

 

Our green rater always performs a blower
door test.

Arlington Designer Homes works with Kelly Ross from Kelly Green Raters to help us certify HERS energy rater to help us quantify total home energy use. Kelly uses sophisticated computer modeling to show how the house will perform and what energy savings we can anticipate over the life of our homes. Most of our homes come in with a HERS rating of close to 50. This means that we are constructing houses that are set to run on almost half as much energy as a conventionally built home.

our green homes. Together we rely on a

 

All the major green building certification programs share the same goal - to encourage builders and homeowners to choose more efficient, sustainable ways to live. Some of these choices are as easy as switching out a light bulb. Others are more complicated, like designing a whole house energy package. Green programs offer us a map to help guide us towards more environmentally friendly alternatives and greater savings, comfort and health for our customers.

Unique Green Home First Completed Under Arlington's Special Use Permit

We are very proud to have just finished building one of the greenest houses in the county! 

This unique single-family home, located on the first pipestem lot to be developed in Arlington County under a new special use permit process, features a living green roof and an advanced storm water management system.



Green Living Roof Under Construction

The new 3,100 square foot, 4 bedroom, 3 ½ bath home, located at 2617 N. Nottingham St., is the first house built under Arlington County’s Use Permit process, established after the county changed its zoning ordinances for pipestem lots. The permit process included extensive collaboration among Arlington Designer Homes, county staff, neighbors and community members, and resulted in a green design that is truly one of a kind.

Responding to county and neighborhood priorities, we committed to extensive storm water management techniques and practices. Our new home showcases what in-fill construction of the future will look like. In fact, the lot will produce less storm water runoff post-construction than it did prior to development.

These storm water management techniques include multiple rain gardens, native plants and grasses, permeable pavers and a living green roof. The Liveroof® system is a modular system where sedum plants that serve to absorb rain and protect the roof are grown in trays and then transported to the building site ready to go. The advantage to this system is that you can install a fully planted green roof in a day.

The house also features an advanced insulation package including both cellulose and spray foam insulation, Energy Star Jeld-wen windows, a high-efficiency furnace with a heat pump, 1.28 gallon per flush toilets, pre-finished flooring and siding, and PVC trim for a low maintenance exterior. It will be certified under the Energy Star 3.0, Arlington County Green Home Choice, and Home Innovation NGBS Green Certified programs (expected).

Our new green home located at 2617 North Nottingham Street in Arlington will be open to the public and prospective buyers this Sunday, April 7, from 1pm to 4pm. Come check it out!

Our Advanced Insulation Package

Insulation is like a wool sweater for your house. It is what keeps you warm on a chilly winter day. Insulation and air impermeability go hand in hand. If insulation is the wool sweater for your house, the house wrap is your rain coat. We can talk about the air barrier later, but today I want to talk about insulation.

There are many different types of insulation on the market. At Arlington Designer Homes, we design our houses using different types of insulation for different reasons. We use a hybrid system which helps us maximize efficiencies. An insulation package that is correctly installed will have contact on all 6 sides: front, back, left, right, top and bottom.

On a typical construction project we will use Demilec Sealection 500 in the places where spray foam is a good fit. These places include the band board, bump outs and overhangs, and as part of the roof assembly.  Spray foam goes on in a thick coat and expands 100 times to fill all the nooks and crannies. It sticks in places where other types of insulation just won’t stay.

Another type of insulation we commonly use is spray-in fiberglass insulation or the BIBS system. This is another great insulation that fills all the cracks and helps to prevent air infiltration. Sometimes we will use a dense pack cellulose in the vertical walls, with the same benefits of the BIBS system.

If you have been reading my blog, then you know that the products we put in the walls and ceiling are just one part of the whole advanced insulation package. We use air sealing (check out our next blog for more on air sealing) to keep the air out and help the insulation perform the way it is supposed to. Advanced framing, proper ventilation, high quality windows and siding, and attention to detail are also all factors in making sure that our houses are properly insulated and extremely comfortable and energy efficient.

Increasing Energy Efficiency with Advanced Framing Techniques

There are many things that go into building a green home. A truly efficient green home is initially designed on paper and then built on the site. There are many homes that have green features, but at Arlington Designer Homes, we believe that to realize a green home's full potential, you need to start at the beginning. Our green homes do much more that create an efficient, comfortable, and healthy home to live in. We also reduce, reuse and recycle our materials to make the whole process more efficient and sustainable.

When we clear a site, we use the trees that must be taken down on site as mulch for remaining and new trees. When we mulch these trees, it helps cover the soil to prevent contamination from entering our streams. The added mulch pad helps to protect existing trees' roots and improves the basic organic composition of the soil for years to come. All this, and we keep these trees out of the landfill. But as I said, that is just the start.

It is important to incorporate green principles from the construction of the foundation to the roof in green home design. Today I also want to talk about Advanced Framing Techniques (AFT). These techniques allow us to integrate green building into the entire home. Some of our AFT are no-brainers, and any team that is not doing them just doesn’t have basic technical knowledge. Some of these items are: insulated headers, ladder blocking and California “T” corners.

An insulated header is the area above a door or window that has added insulation. In standard construction techniques, carpenters put a ½” of plywood sandwiched in between the header material. The plywood is just a spacer, but to us, it is an opportunity. This is an opportunity to add more insulation and therefore efficiency to the house. We put in ½” rigid foam insulation (R-3). It isn’t a high R value, but it costs nothing to do and should be a standard part of an new home being constructed.

Ladder blocking is added where an interior wall meets an exterior wall. Rather than have the interior wall run into the exterior wall and end with three 2x4s in solid wood block, we create a ladder. We string 2x4s horizontally every few feet to fasten the interior wall to the exterior wall. This ladder is not directly in contact with the plywood that is the side of the house sheathing, so we can get insulation behind the ladder 2x4s and create a more efficient house. Where there used to be just wood block, we have eliminated the wood block and added more insulation.

California “T” corners are used where two exterior walls come together. Like ladder blocking, we try to eliminate a mass of 2x4s and wood block and create space where we can add insulation. We do this by doing just what the name implies, creating a T where the walls intersect. This T helps us to get insulation into the corner rather then blocking.

The three examples I gave above are things that all of us at Arlington Designer Homes consider ‘basic’ construction techniques that every house should be using. We use these AFTs, but also go above and beyond by eliminating headers where possible, and using less wood and more insulation in window and doors jacks, along with many, many other techniques that set us apart from those that ‘just build to code’. We build for what the code will be in 20 years.

Conserving Water and Preventing Run-Off

It has been a long road but we are well underway building what will surely go down as one of the most amazing and unique homes in Arlington.  We are excited to be working with many new and interesting systems. Because of the unique position this lot is in, we have worked to design the lot in such a way that there will actually be less storm water run-off post development than pre-development.

In this way we are truly ahead of our time. Arlington, Virginia, and all localities within the Chesapeake drainage basin have been working for years to reduce run-off from farming, industrialization and housing development. During our development process we had our civil engineers work to design the lot in such a way that we will be on the cutting edge of development technology in our area. The technologies we will use to prevent run-off and help do our part to preserve the Chesapeake Bay include:

1.       Rain water re-use

2.       Pervious pavers

3.       Green roof

4.       Bio-retention

5.       Swales

6.       Mitigate time for unexposed soils

7.       Shared trenches for utilities

8.       Area appropriate plantings

9.       Hydro-zoning

Not only will these technologies prevent run-off and pollution into Arlington’s storm water systems, they mean our new home will use less water. We will need less water for bio-retention, pervious pavers, and hydro-zoning, as well as the features going into the house.

The Truth About Trees

People often ask  ‘How can you consider your company green when you cut down trees?’ This always strikes me as a very narrow viewpoint. What we do as a green company is so much more than any one aspect of construction, and tree protection is a very big and nuanced issue. As a green company, we have to balance the needs of our customers, the neighbors, the community and the environment.  In planning for our projects, we take all these factors into consideration.

One of the first things we do when we start a project is develop a comprehensive tree plan. The first part of this plan is a tree survey. We identify all the trees on our property and adjacent properties that fall under our site plan. We identify the type of tree, assess the health of the tree, and desirability of having this tree on the site. Many people aren't even aware that we undertake these studies, but we do one for every single property, to help us protect not only our trees, but also our neighbors’ trees and our neighbors’ property. The studies help us determine which trees should be removed and why, which trees should be preserved and why, and which types of new trees should be planted.

With the house we are building at 2617 Nottingham Street in Arlington, one question I heard many times was "What can we do to save the trees?" In my opinion, the question should have been “Should we save these trees?”  In this case, the answer was most definitely no. Most, if not all, of the trees on the property that we cut down were infested with a contagious, deadly canker disease. The best thing we could have done for the other trees on this property and for the neighbors' trees was to remove them before they contaminated other trees.

In our tree survey, we were able to identify trees that pose a danger to other trees or personal property and remove them. As I drive or walk through Arlington, I see all sorts of trees and properties that would benefit from having an arborist take a look at them. Some are in simple need of having the English Ivy pulled off of them so they don’t choke to death. Others need more TLC, and yet others are dangerous or diseased and should be removed. Our tree survey helps us to identify and remove dangerous and infected trees.

We also look at the desirability and viability of a tree. Many of the trees that we have in our area are invasive non-native species. These species can threaten the health of native plants and animals. That is why as part of any green program you are encouraged to plant native species. We believe in removing invasive species as needed, and planting species that will help support native wildlife, that are disease and drought tolerant, and that have a proven track record in the area.

The viability or life span of a tree is something else that is taken into account when deciding which trees stay and which trees go. The simple fact is, trees have a certain life span and sometimes when you are at the end of it, the best thing we can do is replace an old dying tree with a tree that will be strong and healthy for years to come.

Most of the trees we removed from the property at 2617 Nottingham St. were either diseased, invasive, or at the end of their healthy lifespan. We took our arborist’s expert council and removed the less desirable trees so that we can start to implement our more comprehensive and appropriate tree plan. The tree plans we execute are based upon creating vibrant, lasting trees that will benefit native species along with the homeowners and neighborhood for many generations.

Some interesting and useful related links:

Virginia Tech Cooperative Extension Guide to Problem-Free and Native Trees for Virginia

Virginia Department of Natural Resources Native Plant Finder

Virginia Native Plant Society (has lists of nurseries)

Follow the Construction of our Newest Green Home

Arlington Designer Homes, Inc. is proud to announce that we have submitted our building permit for a new single family home that we are building at 2617 N. Nottingham St. You might have seen us and this property in the news recently. This pipestem lot was created in 1969 and has been taxed as such since its creation, but in 2003 the Arlington County Board changed the building application rules for these types of lots.

Last summer, we became the first applicants in Arlington to file for a type of Special Use Permit under the new application rules for this type of lot. Arlington was a little unsure how to proceed with this new type of permit application, and so out of an abundance of caution, they chose to defer the decision until February. Throughout this time we worked diligently to develop a plan that would meet the needs of our customers, the neighborhood and Arlington County.

Through this process, we came up with a design for the home that will make this a truly unique North Arlington home.  This home will feature a flat green roof, pervious pavers, a bio-rentention area, designated rain gardens, and many, many more features that will help address future rain runoff issues. We plan on creating a site where there is less outfall (runoff water) after the home is built than before. This is just one of the many factors that will make this house so unique, and we are really excited to have the opportunity to build such a one-of-a-kind home here in Arlington County.

We anticipate this new Green Eco-friendly home being built to the Gold standard for both The National Green Standard and Arlington County Green Home Choice standards. This sustainable new home will be a joy to build and an even bigger joy to live in! We anticipate putting the home on the market in January 2013.

Because there's been so much interest in this unique lot and building process, and because this house will have so many special green features, we're going to post a weekly construction blog throughout the duration of the building process. We hope it will be useful resource for other homeowners and builders in Northern Virginia, and for anyone interested in green homes. Stay tuned!