Posts Tagged ‘New Townhomes’
The first sub-category in the “Sustainable Sites” category of the LEED certification process is called “Site Stewardship”.
The intent of this sub-category is to minimize long term environmental damage to the site during the construction process. It’s actually kind of a “duh” aspect of the process because it’s so obvious to builders in California. The extensive Storm water laws in California mandate that we protect the site during the construction process. I built in Texas for many years and there were no laws whatsoever aimed at limiting environmental damage to the site during construction. In California you can face some serious fines if you ignore the law.
From the LEED perspective, Site Stewardship, has only two components to it; Erosion controls during construction and minimize disturbance to the site.
Erosion control during construction is kind of self explanatory but this is the one that can get you in big trouble in California. There has to be a plan in place so that NOTHING from the site erodes off the site. In other words if it rains for 3 days straight, or 30 days straight, not one grain of dirt from the site can end up in the storm drain system. Protections must be in place to safeguard anything on the site from ever leaving the site. Sounds pretty onerous, I agree, but in reality if every construction site had no protections in place, then the storm drain system would be overrun with sediment during any kind of rain event. The only way to fix that is every so often someone has to pay to go clean out tons and tons of sediment from the storm drain system, which is exactly what the State of California was doing for years and years. Billions of dollars were spent dredging all this dirt from storm drain channels until someone finally figured out that if we make laws forcing all construction sites to make sure nothing erodes from the site we wouldn’t have to clean out the storm drain channels so often. LEED awards points for doing just that, but in California you don’t have a choice.
The second component has more to do with design than construction but LEED awards points if those decisions “steward” the site towards minimizing disturbance of the site. If the site was NOT previously developed, and you leave 40% of the buildable area completely undisturbed, you can get points. If the site was NOT or WAS previously developed and you develop a tree or plant preservation plan for the site, you can get points. The best part of this component is if you design with a density of greater than 7 per acre you can receive all the points in this component without doing any of the other things. Being an infill builder, we rarely ever build anything at less than 7 units per acre so that part is easy to achieve.
To sum up this component, we’re an infill builder in California. Those two aspects alone make getting these LEED points almost impossible NOT to get. By law we have to implement erosion controls during construction, and we wouldn’t even consider an infill project that yields less than 7 units per acre.
Next time let’s talk about the “Landscaping” sub-category of “Sustainable Sites”
Sorry for the 6 week gap. City Ventures is growing at an amazing pace and our third quarter was very busy at the end. We now have 18 homeowners living in two of our LEED Gold projects in Santa Barbara and Signal Hill.
But back to our discussion about LEED and how they determine “Greenability”. That’s my new word.
So the last few blogs we talked about Water Efficiency, one of eight LEED categories that garner points towards Certification as a Green Project. Now we’re going to spend a little time on another category. LEED calls it “Sustainable Sites”. Although the focus of green building is on the built structures located on a site, the design of the site and its natural elements can have a significant environmental impact. The Locations & Linkages category, which we’ll discuss next, rewards projects for choosing a preferable site location. The Sustainable Sites category rewards projects for designing that “preferable” site to minimize adverse impacts.
Early decisions about how to incorporate the homes “into” the site can have significant long term effects. The way in which a home is, or is not, integrated into the site can have various effects and the more those effects are minimized, the more LEED points, and thus more green, the project becomes. Site design should take into consideration not only the aesthetic and functional preferences of the occupants but also long term management needs, preservation principles, and potential impacts on local and regional ecosystems.
The category has six sub-categories. First is “Site Stewardship”, which is a fancy way of saying we minimize the damage to the lot during construction. Second is “Landscaping” which is kind of obvious but a pretty broad topic we’ll discuss later. Plus you’ll remember landscaping was a big component of the Water Efficiency” category. Third is “Local Heat Island Effects” which gets into how much of the site radiates heat. It actually has a pretty big impact. Fourth is “Surface Water Management” which is kind of self evident. As is the fifth which is “Non-toxic pest control”. Finally there is “Compact Development” which I’ll explain later.
In fact I’ll start dealing with each of the six sub-categories next time as I didn’t realize I’d be this wordy in the introduction.
So we left off talking about one of the 8 LEED scoring categories. Water Efficiency. Last week I talked about one of the three sub-categories of Water Efficiency; water reuse.
This week I’ll talk about one of the other two sub-categories; outdoor water use.
Outdoor water use has to do with the irrigation system for the landscaping. You’d think that the landscape design and the kind of plants etc would dictate how much water gets used and to a certain extent it does. But in reality it’s possible to have a completely inefficient irrigation system watering an expertly designed LEED certified landscape plan. That’s why landscape is part of another LEED category called “Sustainable Site”. To earn LEED points for outdoor water use, Irrigation systems must be designed and installed to minimize the amount of water needed to maintain the landscape. Although a lot of this is kind of obvious, you’d be amazed at how much is overlooked and ignored in most of the irrigation systems installed.
There are two ways the maximum amount of points can be earned for outdoor water use. One is install a high-efficiency irrigation system and have a third party verify its efficiency. The other is to use a formula that calculates the amount of water needed to irrigate a specified landscape area that takes into account species, microclimate factors and irrigation equipment and then reduce that amount by 45%. If that sounds complicated and subject to serious interpretation issues, I agree. The first way is much easier to comprehend and implement. Here you get points for adopting at least three of 7 “strategies” that create an efficient irrigation system. Obviously it would be most efficient to adopt all 7 but LEED at this time gives max points if you adopt three.
Design a system with head to head coverage is one. Doing this keeps the water coming out of the heads from overlapping each other causing some areas to be watered more heavily than others. A second way is to use drip irrigation on at least 50% of the landscape beds. This puts more water in the ground and less in the air through evaporation. A third is to create separate zones based on the bedding type. More porous bedding types obviously absorb water quicker and can stand longer watering times while non-porous beds will create runoff in the same time frame. Installing a timer is a fourth way. This allows the landscape zones to be watered at the best time of day to avoid evaporative effects and to only water for a specified time related to the needs of each zone. Fifth is to install pressure regulating devices to maintain proper pressure and avoid misting. Misting water never hits the ground and ends up as humidity in the air. Sixth is to use high efficiency nozzles that control distribution uniformity so areas within the zone receive the same amount of water. And seventh is to install a moisture sensor controller that shuts the system down in case of rain. How stupid is it when you see someone’s sprinklers on while its raining.
As I said its best to use all 7 seven strategies but for LEED purposes you max out in terms of points at three. I think over time in locales that have water issues, all these strategies will be law instead of optional, and in reality they should be. As I said before most of the growth in this country is occurring in areas with water issues and learning how not to “waste” water now, makes it easier in the future.
Next time we’ll talk about indoor water use.
So last time we talked a little about water efficiency. I talked about how water is an interesting natural resource because we definitely need to be efficient in its use, but not because of its scarcity. In fact water is basically an unlimited resource. We need to be efficient in its use because it’s a pain in the ass and costly to procure, treat and distribute. Especially if you live in an area where it doesn’t naturally exist…..like most of the southwestern portion of the United States. Of course that’s ironic because MOST of the growth in this country in the last 50 years has occurred in the southwest portion of the United States.
Remember I also said last time that growth can be severely limited by access to water. As a region tries to grow, if it can’t get water, it won’t grow for long. As the costs of getting MORE water to an area increase, it will eventually become a situation where those costs will exceed the ability of that region to grow. If the costs of getting MORE water are prohibitive, then the only way to grow is to use the water that you ARE getting more efficiently.
LEED awards points in their certification process for building new homes and neighborhoods that use water more efficiently. There are three areas points can be earned.
First is the reuse of water. And there’s three ways points can be earned there. First we can capture and reuse rainwater. Obviously it can’t be used for everything as it isn’t treated for drinking or bathing purposes, but it can certainly be harvested and used for landscaping. Of course it’s a little expensive and impractical to try and harvest rain in an area that has little or no rainfall so we haven’t looked at this option very seriously.
Second is the use of “gray water”. Gray water is untreated household wastewater that has not come into contact with toilet waste, kitchen sinks or dishwashers. It includes used water from bathtubs, showers, bath sinks, and clothes washers. Toilet waste and used water from kitchen sinks and dishwashers is called black water. It cannot be reused. Gray water absolutely can be reused for landscaping purposes. A sewer system must be devised that separates black and gray water and diverts them to different areas. This is where the cost comes in. In most communities ALL wastewater goes into the same sewer system and ends up in city treatment facilities. LEED will award points for a project that devises a system to separate and capture gray water so it can be reused.
Third is utilizing a Municipal Gray Water system. Some forward thinking cities have their own systems in place that separate gray and black water. Building a project that hooks into that system gets LEED points as it helps use water more efficiently.
The other two areas LEED awards points for has to do with outdoor and indoor use. I’ll address them next time
So last time we talked about Sustainability.
If the energy required to operate the homes in our neighborhoods actually came from our neighborhoods, then we can call those neighborhoods “Sustainable”. They “sustain” themselves without the use of any “natural resource produced energy” to operate.
But is the energy to operate the homes we live in the only aspect of homebuilding that requires the use of natural resources? And therefore the only way we define whether or not a home is “Sustainable” or “Green”.
Of course the answer is no. In fact there are several natural resources used not only in the production and operation of homes and neighborhoods but also used as an indirect result of WHERE homes and neighborhoods are produced.
Gee, what we need is a way to measure how “Green” a home is and use that standard of measurement as a means of letting the public know which homes are green. It turns out we do! Its called LEED certification. LEED stands for Leadership in Energy and Environmental Design. It’s a point system that encourages the production of “Green” homes by awarding different certification levels. The levels are basic LEED certification, LEED silver, LEED Gold, and LEED Platinum. Obviously the higher the certification level, the “Greener” the home.
There are two reasons a homebuilder would seek LEED certification. First, it’s the right thing to do. I know that sounds pretty new-agey. But we can’t keep building homes/neighborhoods/cities the way we always have. It’s not only irresponsible but it’s about as shortsighted and selfish as it gets. It unnecessarily wastes future natural resources for present economic gain. That’s just wrong. Secondly, and as I said earlier, it lets the general public know that the home they’re purchasing is green. For the same reason homebuilders need to stop building homes that aren’t green, the public needs to stop buying homes that aren’t green. It’s just wrong and it will get more wrong as time goes on and the battle of demand of natural resources versus the supply will inevitably push the equilibrium price of all natural resources beyond what anyone can afford to pay. Until they’re gone….and unavailable at any price.
That’s why the future of homebuilding is through green building practices with the ultimate goal of producing net zero energy homes that are 100% sustainable.
The first one to figure it out wins. And that’s my goal.
Next time we’ll talk about those other aspects that make a home green