Welcome back to Green Building 101. In our last post, we touched upon how to select an environmentally responsible location for your new abode, and in this piece, we’ll begin to discuss ways you can improve upon any home site. The “Sustainable Sites” section of USGBC’s LEED for Homes program outlines various “green” opportunities for reducing the negative impact your home has on the environment. Most of these principles can be implemented at any time, whether you’re still in the design process or if you’ve been in your home for years. Here are a few measures you can take to create a more sustainable site:
Time and Nature Have Sculpted Your Land: Consider This an Asset
Most importantly, use what nature has given you by working with existing topography, plants, and views. Touch the earth lightly, rather than cutting deep and covering it with concrete. (If you bought the land to scrape it, you might as well be building on a K-Mart parking lot.) As an example, the eco-friendly Tinbeerwah House in the Australian Noosa Hinterland, shown above: the home was constructed on top of a unique grid system of steel portal frames that elevate it above a steep slope in order to minimize site disturbance.
Vegetation is Good; Native Vegetation is Better
Landscaping is a critical component to the livability of any home, but people often optimistically misjudge the viability of plants. First, make an effort to preserve any existing native plants, as they obviously like where they’re living and can possibly be groomed into a low-maintenance greenscape. Second, work with a local gardening supply store (not a Big Box) to help you select plants that will grow best with your local climate and soil conditions, thus reducing the need for excessive watering. Third, seek out organic options for fertilizer and herbicides/pesticides to prevent any longterm negative impact in the local ecosystem and water table.
Related: Los Angeles Pays Residents to Rip Out Their Lawns
Shade, Shade, Shade
Your driveway, sidewalk, and paved terrace all absorb the sun’s rays during the day, storing it like a battery, and radiating that energy back—even at night. These “hardscapes” form microclimates of hot air pockets that are not only miserable for people, but take a huge toll on the cooling bill of any nearby building. At the city scale, dense collections of hardscape add up to a lot of heat known as the urban heat island effect, so the more you can keep these areas shaded, the better off you (and your city) will be. Think trees, pergolas and canopies—oh my!
For you advanced players in the heat dissipating game, there’s no place left to go but up: Green Roofs!! Here at Inhabitat, our love of green roofs runs a close second only to prefabricated buildings. There is a huge variety of green roof construction systems to fit nearly every building type and location. Stay tuned to Inhabitat for more on greening your roof in the near future.
Where is Your Water Going?
Maybe you’re not yet ready to capture and recycle rainwater, but any precipitation that isn’t soaked up by your lawn runs straight into your city’s storm water system. While this is a natural thing for water to do, it nevertheless picks up things like oil, antifreeze, fertilizer, and pesticides that may have accumulated in your yard or driveway, contaminating the water system and contributing to erosion. You can reduce this negative environmental impact simply by directing run-off from driveways and gutters towards your lawn, and providing enough of a depression for the grass to hold the rainwater longer, allowing it to filter naturally through the soil.
Not All Bugs are Bad!
Rather than spreading poison to eradicate pesky aphids from your tomato plants, consider some of the alternatives. Organic pest control has finally become widely available, so in addition to homemade sprays made with glycerin and essential oils, nematodes, diatomaceous earth, and orange peels are just a few of the ways you can fight insects without chemicals. Your local garden supply stores should be able to help you choose a product for your specific problem, and doing a bit of research on organic methods of pest control can’t hurt either! Remember thatinsecticides affect beneficial insects too, and with the startling decline of bees around the world, it’s better to be safe and gentle to your garden rather than risk killing any more of them off.
Related: Attracting Pollinators – Plants that Encourage Bees, Butterflies, and Birds to Visit
Our next piece will focus specifically on water conservation, both inside and outside the home, so stay tuned!
For Nina, You can build on piers to elevate the home and still be energy efficient. The solution is to have your walls extend all the way to the ground. You want your crawl space below to be enclosed and not be vented. You will want to put a moisture barrier down over the natural ground to keep moisture out. You will see how the space conditions itself to coexist with the home above. There will be no need to insulate the floor since you insulated the exterior walls down to grade. As previously mentioned, go to Building Science site and take a look at their builidng designs for pier and beam construction.
David is absolutely right, Edward Abbey thought the same thing 40 years agobut we kept building. Europe knows all about "limited space" and handles it fairly well-- why do we always think we have to reinvent things, look around. There are places going in the right direction--Portland with its building boundaries. Have to give China and Bill McDonough credit for rethinking the city and moving all the green up one layer--if you have to build new. The Historic Preservation and Green movements are finally converging-to everyone's benefit. Recycle, Reuse and Respect what came before. Gentrification is a side-effect. Is it always bad? always good? no. but rebuilding what we have is better than building on farmland or habitats.
For young architect Nina - Consider berming your house into the hillside, i.e., dig out a foundation and use the soil on the north or west side to serve as insulation. Also, if you decide to do a green roof, remember that sedums are not native and are potentially invasive. They make sense in cities but not necessarily in rural areas. David - I agree completely that we must stop developing previously undeveloped land - and especially undeveloped land that is not too far away from cities, because there is so little of it left. It should be regarded as a common good, and governments should buy it or should reimburse owners for the ecosystem services provided so that they have an economic alternative to developing it. This also applies to farmland near cities. As petroleum and water prices rise, it will once again become prohibitively expensive to transport staple foods thousands of miles. Louisa
Hi Sarah- I don't know if this helps, but check out some of the US Governments energy policy tax incentives for green renovations: http://www.irs.gov/pub/irs-drop/n-06-26.pdf http://www.energystar.gov/index.cfm?c=products.pr_tax_credits#chart Hope that helps! -Jill
Just wondering if you guys have any leads on grants available to NYC homeowners who want to incorporate green and sustainable elements wherever possible in their remodel?? Any input would be much appreciated - we are about to close on a house in Brooklyn, and putting together a budget -- would love to do some "leading by example" (we are dismayed by all the crap that is going up in our quickly-gentrifying 'hood). Thanks, Sarah
The problem as I see it is that we are still developing undevloped space. I think that has to STOP NOW if we are going to be able to address climate change and enrgy. Where is the movement to retrofit our exsisting houses to transition them to green efficent homes. I think it is time to tear out the grass and re-veg with natural vegetation, and get these structures more energy efficent. If that is not possible then we need to remove the old and replace them with green. But we have to stop development of the natural space we have left. Soon all of the open land will be gone, developed into green structures, that will not solve the problems we are facing. We need to work with in developed areas to make them sustainable. We need to rethink the whole deal before its to late. reclaim, recycle those old houses. Work with your community to establish new rules for development and URBAN Renewal.
[...] This one relates back in large part to our discussion of sustainable sites. The conditions under and around your home determine the ability of the structure to withstand all sorts of potential challenges to its integrity, not least of those being moisture, wind and temperature fluctuations. This is also tied into considering the offerings of local resources, as the naturally-occuring materials in any given location are most likely to be durable within that region. A great article at GreenBiz talks covers durability in depth, addressing not only the weather-related issues, but also insects, function, and even style. [...]
[...] As was pointed out in last week’s Green Building 101 installment on Sustainable Sites, it’s wise to choose landscaping elements that are appropriate to the climate and require minimal water. Because of their varying root systems, grass, trees, and flowers all have different water requirements. When you design your garden, consider the layout of the irrigation system, and try to arrange plants according to the amount of water they need. [...]
N.: The previous posts/sources are all great. My own 2 cents: To not waste that precious "green" warmth you'll be sieving out of the ambient, you'll have even more need of top notch insulation, weatherizing and tempering. Harder to do in a cold area on stilts - but possible. Also: read about solar heat for midwesterners or non-Colorado/non-California types with Don Stephens' "Annualized GeoSolar" designs at http://www.greenershelter.com/index.php?pg=3 & look around for strategies used in zero energy designs for a northern locale. -from a techie not an architect
I'm delighted to have found your site from http://www.architectureweek.com/. I look forward to the Green Building 101 series and other explorations at your site. May I suggest adding Table of Contents links to the Green Building pages, so that someone jumping into the middle of the series will be able to easily navigate to the start or wherever their interest takes them. --David
Like all green building deisgns, you need to draw a line in the sand, because no matter what you do, someone will critize you for it. As for your concern of the foundation you have three issues you must wrestle with. One is you want to tread lightly on the earth. Second is energy efficiency. Third is resale value and marketability. Now I am not sure where in up state NY this house will be. But growing up in Rochester with harsh winters, putting your house on post would not be your best option for energy efficiency. I would recomend looking at some foundation details at www.buildingscience.com. I have been working with this organization on a green home and they look at the home as one big unit to make it more energy effiecient and most importantly a healthy place to live. But you can still tread lightly on the earth by following one of Le Corbusier's 5 points of architecture and replace the earth you have desturbed on the ground an build a roof garden or green roof. There are many examples of residential green roofs.
Dear nina, In response to the last post... Every site calls to different needs. Louis Kahn would say it is important to ask a brick , for example, what it wants to be... you may want one thing, but it insists on something else. Ask the site what it wants to be. Glen Mercutt's response to his site was to raise the building, and this was due to his consideration of the site's environment and the needs and desires of the people. The physical manifestation from his method is something that fits his particular site's context. I imagine your site's context is different, and thus the response you create architecturally will be different. Who knows, it might be similar, but whatever it is, the site and the context should help lead you to the generation of form. Methods of considering sustainability should be reflective of place and its essence. I believe this is a key point the "Green Building 101" series has been discussing. best, -matt
this information could not have come at a better time for me, a young architect who is about to build a free-standing house for the first time. (not much free-standing work in nyc!) i was wondering, though, how to resolve the foundation. the house is in upstate new york, and while i would love to "touch the earth lightly" by putting it on posts, i'm afraid that all the cold winter air traveling underneath the house would lead to increased energy usage (although we are going to use solar panels on the roof and geo-thermal heat). is it really so bad to cut a small foundation into the ground? any advice is welcome.