Tour de LEED: Homes

leedlogo2This coming Saturday ours is one of three homes being toured by the North Texas Chapter of the US Green Building Council.  We moved in 3 weeks ago and are hustling fast and furious to get the house presentable.  We’ve given our builder this Thursday as their deadline to be done and out (we’ll finish anything remaining undone after that).

The tour is featuring one LEED for Home certified Platinum house, and 2 LEED for Homes registered Platinum house.    Sign up quickly!  They’re limiting the tour to 60 participants!

Cabinets and Wood

cabinets01032009Our cabinets started getting delivered this past week over the holidays.  They are really spectacular-looking and (you guessed it) environmentally friendly (photo is of the master bathroom vanity).  The cabinets are locally produced here in Dallas.  The Materials & Resources category of LEED for Homes allows us to claim points for using a local supplier.  So think of it this way:  we could have cabinets fabricated in, say, California.  The fabricator would ship them to Dallas.  When they are shipped, however, most of what is being shipped is air because the cabinets are mostly open space.  With the cabinets made in Dallas, the wood can be locally sourced from the forests in Arkansas and Oklahoma and shipped to the fabricator in stacks so that more material is shippped at once.  Then the cabinets are made and brought the final 10 miles to us – much more efficient.

Had our cabinets been constructed with tropical wood, we would have had to use FSC-certified woods.  The Forest Stewardship Council (FSC) is a non-profit, non-governmental organization that was created “to promote the responsible management of the world’s forests.”  Basically the organization creates standards that allows the end buyer (us!) to be assured that the wood we’re buying has been grown, harvested and transported in both an environmentally-friendly and a human rights-friendly manner.

Section 2.1 of the LEED for Homes Materials & Resources category requires the use of FSC-certified tropical woods.  We’re having a bit of a hard time finding a supplier of garapa, which is what we’re hoping to use on our upper balconies and bridge.  There is wood available that is not FSC-certified, but its use would negate any LEED certification….obviously not desireable!

Exterior Finishes

I wanted to create a short post to talk about exterior finishes and why we chose them.

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  • Brick – a green material that is highly durable.  Brick can last for decades with minimal maintenance.  Our brick was made locally so transportation costs were minimal both in dollars and carbon footprint.
  • Concrete board – also a green material and highly sustainable.  This product looks contemporary, can be used for multiple applications (both on the outside walls and in the exterior sofits).  This material is also very affordable and easily replaced if a board gets broken.  The photo above shows the concrete board and Cedar Siding on the garage/studio structure (I decided I had posted too many photos of the front of the house lately!).
  • Cedar siding – a fairly green material.  We debated about how much wood to put on the exterior.  The result was a moderate amount – enough to make the home’s exterior aesthetically pleasing.  This material is sustainable and long-lasting.  Also, we opted for a “non-clear cedar”, meaning we decided to have a large number of knots in the wood.  While the prevailing wisdom is that clear cedar is more pleasing to the eye, I like the more informal look of the knotted cedar that we used.
  • Metal – green and durable as well.  We have metal windows, a metal roof, and metal sheathing around the top of the house and around the front window structure. 

These selections – along with our energy-efficient windows – create an environmentally-friendly fascade that is also aesthetically pleasing. 

The paints and stains on the exterior of the house are not low VOC.  We decided to use low VOC on all interior paints and stains, but not on the exterior.  We were looking to save a little bit of money and chose to go traditional.  LEED is very concerned with interior air quality and not so concerned with exterior finishes.

Hot Water Heaters

We are using tankless hot water heaters for our house.  We actually have three:  two in the main house and one for the studio.  We aren’t installing hot water in the outdoor bar area (I hear it’s traditional that you don’t have hot water at a bar sink…who knew?!).

Gas tankless hot water heaters are the most efficient to use, heating water only when the appliance senses water flowing through it.  And while the heater gives a huge blast of gas-powered flame to the water as it flows, you’re not paying to keep a 50 gallon tank of water hot 24/7. 

Our house design is very conducive to efficient use of tankless heaters.  The north side of the house accommodates the master bath (downstairs) and the kitchen (upstairs).  The south side of the house accommodates two guest baths and the laundry room.  By installing two heaters – one on the north wall and one on the south wall – we minimize the length of the pipe runs from heater to end-use faucet or appliance.  LEED awards points (in the Energy & Atmosphere category) for keeping the pipe runs under 20 feet for 1 story homes or 20 feet + ceiling height for 2 story homes.  So for our 2 story home, we’re allowed runs of 29 feet.  Our longest run is approximately 20 feet.  The photo above is of the interior/backside view of one of the tankless heaters.  Ours install on the outside of the house…and you’ll note that it backs up into the master wet area that houses our tub and showers.  We’re very close to our hot water source…which will be nice on those rushed or chilly mornings.

We’re reusing one of the hot water heaters from our old house.  We loved it, had absolutely no issues with it and would recommend it to anyone.  It is a Noritz.

Fireplace…or not?

We wanted a fireplace in our house.  Unfortunately LEED rules didn’t allow it.  We knew that a big, traditional fireplace wouldn’t have fit into our modern home, but we also knew that an open wood-burning fireplace was out of the question in a Green Home.  So, we looked at a couple of options, the most promising was the ecosmart fireplace.

They are beautiful and, at first look, Green!  They basically consist of an open flame burner that utilizes denatured alcohol (aka ethanol) as the fuel.  We were going to use ethanol from corn to make the fireplace even Greener.  Our architect designed an ecosmart fireplace into our living area.  It was going to be spectacularly beautiful.

Then we met with our LEED Home Provider that I mentioned in earlier blogs.  He quickly cited the LEED category EQ2 prerequisite that says “all fireplaces and woodstoves must have doors”.  EQ2 also states that space heating equipment that involves combusion must meet one of the following:

  1. “…be designed and installed with closed combustion (i.e., sealed supply air and exhaust ducting.”
  2. “…be designed and installed with power-vented exhaust.”
  3. “…be located in a detached utility building or open-air facility.”

Obviously our idea of a sleek, modern ecosmart fireplace didn’t fit with these restrictions.  The whole point of these tremendously beautiful fireplaces is that they are freestanding and open.

Ecosmart touts their fireplaces as Green and clean, which they are – compared to a traditional wood-burning fireplace.  However, when we read the fine print, we saw that even ecosmart had a caveat that supported the LEED position.  In this page of their website, you’ll see the disclaimer about ventilation.  Their smallest burner shouldn’t be installed in (1) a house that is tightly sealed – which most LEED houses are, and (2) in a room less than 1000 square feet large – and that’s a pretty darn big room!  Our house is going to be sealed with icynene insulation, so strike three:  no fireplace.

One last note.  If you look at this website that showcases the first LEED Platinum home, you’ll see that it features an ecosmart fireplace (click on #s 4 & 8 in the diagram to see the fireplace).  Here’s the deal:  this home was built to the LEED for Homes pilot standards which were tightened up when the final regulations were published in January 2008.  The prerequisites in the Indoor Environmental Quality (EQ) section that did us in were added with the final regs.  Don’t think we didn’t fight our Home Provider over this!

Materials & Resources (LEED MR Category)

This category addresses those areas of Green Construction that most people are familiar with.  Bamboo flooring, low VOC paints, locally-source materials:  these are the mainstays of environmentally friendly building materials.  The MR category addresses the materials that make up a huge portion of your house, and the vast majority of the finish-out materials. 

To determine the number of points we were eligible for in this category, we reviwed 21 groupings of materials to determine if the materials we are using are:

  1. recycled or reused
  2. had low emissions (low VOCs), and/or
  3. were locally produced

Points are potentially awarded for all three of these characteristics – so if you used wood flooring that you salvaged from a barn less than 500 miles away you get points in both the ‘recycled’ component and the ‘locally produced’ component.  We believe we’ll end up with the maximum number of points for this portion of the MR category.  We’re using materials such as 30% fly ash concrete, bamboo floors, FSC certified woods in our millwork, recycled oak hardwood floors (from the house we deconstructed), locally produced windows and window frames, locally produced cabinetry, low VOC everything, and we have 100% hard surface flooring (meaning no carpet in the entire house).  I’m going to highlight several of these materials in my later posts because we’ve done some really fun things with these products.  The LEED Environmentally Preferable Products chart on Page 80 of the LEED for Home Rating System document is very informative – although it looks scary when you first see it.  Take time to study it and ask me any questions you have. 

The MR LEED for Homes category also addresses the planning that goes into the framing of the house.  Obviously, the framing makes up the vast majority of the wood portion of the house, so LEED cares about whether you’ve planned appropriately and didn’t order too much wood or wasted too much wood in the building of your house.  As a prerequisite, you have to order no more than 10% in excess of what it will take to construct the house.  If you over-ordered more than 10% you’ve missed the prerequisite.  Extra points are received for having detailed framing documents (which we did thanks to the engineer and architect we hired), and for having a detailed cut list (which we had).

Framing efficiencies can get you 3 points.  There’s a chart on page 78 of the LEED for Homes Rating System that outlines 13 types of efficiencies that you can earn points for.  We are following these, some of which are often collectively called “advanced framing techniques”.

  • Stud spacing great then 16″ on center (we don’t have every single stud spaced greater than 16″, but the majority are)
  • Floor joist spacing greater than 16″ on center
  • Roof rafter spacing greater than 16″ on center
  • Size headers for actual loads
  • Use 2-stud corners (also known as California corners)

Why do we care about having greater than 16″ on center studs, joists and rafters?  As LEED puts it, “Reduced framing can reduce the number and size of thermal breaks and increase the amount of insulation installed, leading to better energy performance”.  And it clearly allows you to use less materials.

Waste Management is also addressed in this category.  You must have a construction waste management plan, and you can get extra points for limiting the waste.  I’ll again refer you to a table showing the amount of points you get (page 84 of the Rating System), but the idea is to send to the landfill or incinerator as little as possible.  Our wood waste is minimal because as you read in my post on the deconstruction of our old house, we are having our bare wood shredded to be used as mulch in our new landscape…so ZERO of it ends up in a landfill!

Materials & Resources expected points:  16 out of a possible 16.

Energy & Atmosphere (LEED EA Category)

The Energy & Atmosphere category can be a little confusing.  USGBC has created alternate paths to earning points for Energy & Atmophere.  Our Home Provider only supports the path that requires a rating using the HERS Index.  According to the government’s Energy Star website, a HERS Index is

a scoring system established by the Residential Energy Services Network (RESNET) in which a home built to the specifications of the HERS Reference Home (based on the 2006 International Energy Conservation Code) scores a HERS Index of 100, while a net zero energy home scores a HERS Index of 0. The lower a home’s HERS Index, the more energy efficient it is in comparison to the HERS Reference Home.

Each 1-point decrease in the HERS Index corresponds to a 1% reduction in energy consumption compared to the HERS Reference Home. Thus a home with a HERS Index of 85 is 15% more energy efficient than the HERS Reference Home and a home with a HERS Index of 80 is 20% more energy efficient.

Our preliminary HERS Rating is a 69.  Our rating could have been lower if it wasn’t for the number of windows and lights in our home.  When performing the preliminary rating (which is based off of plans and a conversation about design and use of the home), our Home Provider also gave us a list of things we could do to get a better rating.  We have agreed to incorporate better insulation in a few areas and to upgrade our windows in the front window tower.  But upgrading the tankless hot water systems would cost significantly more so we chose not to do that, neither did we choose to reduce the window-to-wall ratio.  We have a ratio of 30% now, and to get a six-point decrease in our HERS Rating we’d have to reduce it down to 22% – given the fantastic design of the house, that just wasn’t feasible (although we did go through the exercise to see if it was possible).

One more point to make about the HERS Rating:  they take into account not only how the house is being built (windows, doors, insulation type, HVAC type, construction methods, etc), they take into account the heat gain of the items in the house.  So every appliance or component that emits heat is measured – refrigerator, stereo, computers, etc. – because the heat that they generate has to be countered with cool air, which requires electricity, which is energy, which is what we’re trying to use less of.

While the EA Category for us focused primarily on the HERS Rating, there are a few other areas where we could gain points.  We obtained points for our hot water distribution system.  While we didn’t upgrade to the super-duper tankless heaters, we are using tankless throughout the house.  And we got points not only for the tankless heaters themselves, but for the fact that the heaters are located close to the faucets they serve (no more than ~30 linear feet).  The idea being that when you turn the hot water on in the shower, you don’t waste water or energy waiting for hot water to travel the pipes to the shower head.  We also get a point for insulating all hot water pipes 90 degree bends…apparently that’s where hot water pipes lose most of the heat of the water.  We also got points for refrigerant management.

To get a good sense of the practices that you will end up using regardless of whether you use a HERS Rating or not, look at the alternate path in LEED.  The following categories are addressed, and we could have gotten a good number of the points in that path.  Let me know if you have any questions about these categories:

  • Insulation
  • Air Infiltration
  • Windows (we struggled with windows and I’ll blog about them separately)
  • Duct Tightness
  • Space Heating & Cooling
  • Domestic Hot Water
  • Lighting
  • Appliances
  • Renewable Energy 

Pointwise, the EA category is our weakest, again mostly due to the amount of windows and lights in the house.  We may earn a few more points if we get a better final HERS Rating, but the category will still be our weakest.

Energy & Atmosphere expected points:  18 out of a possible 38.

Location & Linkages (LEED LL Category)

Location & Linkages addresses the home’s access to things like already-existing utility services, public transporation, and neighborhood services (like grocery stores, dry-cleaners, churches, etc).  The less you’re having to bring in brand new water or electric lines to the area, the less energy and materials your house construction will use – and the smaller the negative impact to the environment.  The closer you are to neighborhood services and public transporation, the less likely you’ll be using your car to drive long distances to reach them.  So therefore, it’s easier to build green in existing neighborhoods than in brand new ones (although there are points for developers who are building new neighborhoods that are LEED compliant).

Honestly, we lucked into our LL category points because we chose the house and location long before we ever heard of LEED.   We in all likelihood wouldn’t have sold this house and moved elsewhere just to gain a few more LEED points.  We love our neighborhood – although we could use a few less McMansions (so two words to sellers and real estate brokers and developers:  Stop it!).

Because our neighborhood, Shorecrest Estates (which is bordered by Lovers Lane, Lemmon Avenue, NW Hiway, and Midway Road – – we’re on the cheaper, west side of Midway!), was established in the 1950’s, we obviously are building on a previously developed site, and we already have all utility services available.   And while the Retail developments at both Midway & NW Hiway and Lemmon & NW Hiway are over 1/4 of a mile from us, we do have multiple DART bus stops up and down Lemmon and Midway that allow us to get the maximum 3 points for “Outstanding Community Resources/Transit”. 

One question we never got resolved – but doesn’t matter to us because we qualified for the maximum points in this category already – was whether you’re supposed to measure distance as you would walk it, or as the crow flies.  Our bus stops qualified measuring as you would walk the distance, but our community resources didn’t.  It seems that these distances should be measured as you would walk since the idea is that the services need to be close enough to make you want to walk versus drive.

Proximity to established green spaces counts, and we’re very lucky to be located about 1/4 mile away from both the Bachman Creek Greenbelt and Field-Frazier Park.  These are both very basic but very nice green spaces.

Expected Location & Linkages points:  10 out of a possible 10.

LEED Categories

I’m going to start giving some insight to the LEED for Homes point categories.  Some of it may be dry, but it’s the type of information that I would have wanted to read when I was first starting to learn this stuff.  I’ll explain the category, talk about how we reacted to it, and tell you what points we expect to get in that category.  I’ll probably intersperse the category discussions with other posts, but I intend to get through all the categories….

Is this going to be helpful to you?

Getting Started

Welcome to our Green Labron blog.  Our intent with this blog is to track the design, construction, decision-making process of our home on Labron Avenue in Dallas, Texas.  We intend to build Green – meaning we’re targeting a Platinum LEED for Homes Certification from the US Green Building Council.  We’ll explain what that all means in future posts, but for now….Welcome and check out our links to learn more about USGBC and LEED.