Green Buildings, Green Queens? Green LA?

There's so much going on these days in the sustainability movement in New York & beyond, it's hard to keep up. Green Buildings NYC notes that the Borough of Queens is getting in on the action. The Queens botanical garden's new building is looking to get LEED Platnium and draw over 17% of its electrical needs from a small solar panel array. GBNYC also notes some new solar powered trash cans and that there is enough roof space from old former industrial buildings in just Long Island City alone to make green roofs with the same square footage as Prospect Park.

One point that GBNYC has noted in it's coverage of green building laws in Boston and some proposed legislation in Nashville is that they do not slavishly follow LEED, which was always meant to be a voluntary system, not necessarily a model for legislation. I agree. LEED is a good model, but each locality must define it's own sustainability agenda and figure out how their Green Building legislation helps achieve those goals To that end, the GB blog franchise is expanding to LA.

I think New York's green building laws should focus more on reducing the urban heat island effect, reducing peak electrical demand and reducing the need to drive to the location (near mass transit and bike friendly parking). While in LA, water usage may be a bigger concern.

And if you're a huge green building buff and love talking about Insulated Concrete Forms (ICFs) or Structural Insulated Panels (SIPs), check out Green Building Talk.

I would like to build a "green" home but all what I have seen are for movie star incomes..

If there is going to be conservation in home construction and energy use, I feel they are going to have to be smaller and affordable (simple).

Anyone built a small simple structure for the post oil future ??

Hello jmgygann

"Green" homes can be built at costs comparable to traditional homes- or far lower if you want a straw bale - or Earthship buildings. What makes a building "green" is often a minor extra cost, compared to total cost.

The concept of "green" has to be defined also. Some green concepts are based on using recycled materials, others on using nature materials and yet other on reducing the resourse use and impact on nature. So make your pick.

To me a green Home is a building that has the lowest resource use and impact on nature through the building life 50-75 years. This includes maintenance.
With a tool called Life cycle assessment (LCA) you can actually calculate the Energy use and the emissions produced for making the building materials, for building the home and the energy and emissions produced during the building use during 25,50,75 or more years including maintenance.

The LCA shows that for almost all possible building types, the energy consumption during use ( heating, cooling, hot water and electricity) is the dominating impact on nature, regardless of the climatic conditions. In Europe this is some 40% of all energy use.
In Europe, the tradition is mostly Brick, concrete, expanded concrete and in Scandinavia some wooden houses.

Some LCA numbers can illustrate this. (Forgive me for not using btu and ft2- but they can easily be converted). Brick cavity wall home weigh approx. 1 ton/m2 and consume 1 barrel of oil energy/m2 floor area for producing and installing materials. Maintenance during 50 years (10-25% add on- fx window double glazing replaced each 20 years.)
A wooden home cost some 20% less energy for building materials and installation. A higher replacement rate and maintenance usually evens this out during the 50 Years of use.

The average energy use for heating in EU homes is 150 kwh/m2/year = 15 liter fuel oil/m2/year. In 50 years this alone is close to 5 barrels of oil energy.
So building materials for 1 m2 = 1 barrel, Building heating of 1 m2= 5 barrels. Add to this cooling and hot water and electricity. So the "green" basically means reducing heating/cooling energy use. So how is this done in green building?

With EU numbers.
First the heat loss must be reduced. Then we can later add solar heaters and PV etc. But the base consumption must come down.
Of the 150 kwh/m2/year heating energy some 55 kWh/m2/year is heat loss from cracks and ventilation. So seal the cracks. The rest - 90-100 kWh/m2/year should be reduced with a combination of insulation 250-500 mm depending on climate, better insulated windows - trible glazed windows with insulated frames and doors and ultimately ventilation systems with heat recuperation. Add good workmanship and your heating energy use will go down to 15 - 50 kWh/m2/year. 1.5 - 5 liter oil energy. A solar heat panel of 1.5 m2 per person will suffice for 70% of all hot water, and PV panels can be added for electricity. Cooling is not used videly in EU today, so it is not included.
In environmental (LCA terms) the energy payback time (Energy saved/energy invested) is approx 1 year for solar heat and 1-6 months for Insulation, depending on thickness. Energy payback for PV elements is 3-5 years- and as comparison large wind generators (>1 MW)have a energy ( and emission) payback time of 8-12 months.

The most optimized "green building" concept today is the German Passivhaus - concept (passive house - less than 15 kWh/m2/year for heating). Some 6-7000 have been built today and several houndred have measured data, available on the internet. The Passive house concept can also be used in renovation of old buildings, but heating energy use will end higher.
The extra cost for a Passive house is plus 10-15% for a single family home. Less than a new kitchen or a new bathroom. This is usually saved within a few years in heating costs.
Needless to say that smaller and compact buildings have lower energy use.
An average Danish family home is approx 110 m2 today and in the US it is 230 m2.

Wikipedia has a couple of nice overall papers which I would recommend.
If you follow the links you will see most of the green solutions available.
Re. Passive houses
If you need more info, you could Google "passive house" or "Passivhaus". If you want to see how they look use google images.
There is a ton of info available- also in English.


I built about 15 spec homes over the last 4 years, and have many friends in the business. At the end of the day, its all about profit. I am not building any more homes for anybody. Most people do not care about energy use or green building, just square footage and cost.

I am currently designing my personal Chesapeake Bayfront home now. Will be about 900 square feet, and it will be simple.

Building green is somewhat of a nebulous proposition. The article above talks about ICF construction, and there is nothing green about concrete. IMO, the best thing anyone can do is to design and build around the idea of minimal energy use.

I have been somewhat freaky about energy use for about 20 years, and learned alot. The most important thing is your/family personal habits. For example: I moved in with a women and her two teenage daughters. Average electricity use was about 2200Kwh per month. Now its about 800. This was accomplished by using the woodstove that was already installed, using an Energy Star window shaker for A/C, CFL's for general lighting, low flow shower heads, eliminating the use of the electric clothes dryer, not using the oven to cook a frozen pizza when its 90F outside, etc,etc,etc. Most people do not think.

As far as building goes, the most important lessons I have learned that impact energy use:

- Central A/C and heat is NOT as efficient as point of use.

- Energy Star appliances make a big difference.

- Proper building techniques. Control moisture.

- House orientation on the building lot and taking advantage of solar gain or keeping trees that block western sun exposure for warm climates.

- Use the best materials available that last, and install them correctly.

- For the green side, use natural materials instead of synthetics. (Wood siding, wood flooring, etc)

I could really go on for a hundred pages about this topic. The reality is that most people can build (or retrofit) a house that is enviromentally friendly and energy efficient for a small cost premium ,today. Energy is just way to cheap to force the mainstream to move in that direction.

Personal habits make a big difference, no matter how green or efficient a home is. Robert Rapier posted a nice article about his friends green house in the Colorado hills. He was using a gas fired clothes dryer in a desert climate!

I'm on the fence in regard to Concrete.

It gets overused, and built and then stripped out again, which is a huge carbon gain..

..but again, if you're looking for durable construction materials, it's possible to create elements of a structure with concrete that could serve for hundreds of years. Some Roman concrete is still secure today. (Properly designed, mixed, applied and maintained, of course) So with that potential for quality and length of service, I wonder if Concrete doesn't earn back its carbon costs..

I was on the 20th floor of a hi-rise condo under construction in Tribeca, gazing out the concrete slab and walls, steel studs and gypsum board. I realized that there was very little carbon in any of these materials and it occurred to me that perhaps it's time to take a look housing developments (one and two-story, not hi-rises) with respect to carbon.

Would it be appropriate to look at a development of stick-built houses as a collection of "carbon-sequestration units"? Is there an argument to be made that building out of wood sequesters a significant amount of carbon?

Using some data from DOE, a 2700SF house contains 13,800 board-feet (BF) of lumber (I suggest ignoring the question of whether a 2700SF house is green in and of itself for now). At 12BF per cubic foot, that's 1,150cu.ft. of wood. At 25lb/cu.ft. (a real rough estimate for oven-dried wood), that's 28,750lb or over 14 tons of wood. Assume 50% carbon content and you have 7 tons of carbon or the equivalent of 25 tons of CO2 in a house. I expect these values could change under some scrutiny.

It certainly wouldn't offset all the carbon emissions attributable to the house over its lifetime and my cursory analysis is ignoring a bunch of other inputs and outputs (such as where and how the wood was harvested and what occupied the land before the house was built). Has anyone done a formal study of whether stick-built construction has any positive attributes viz. carbon emissions or sequestration?

I am surprised at your observation.

The world cement industry is 5-10% of all CO2 emissions.

Similarly steelmaking is a CO2 heavy activity. And the steel probably comes from a long way away.

I haven't looked into whether a concrete and steel house is as CO2 intensive as a wooden one. Perhaps the gain (if there is one) is that a concrete and steel house should last a lot longer than a wood one.

*that said* they are tearing down concrete buildings put up here in the 60s (London). They cannot take the constant wet-and-drying-out cycle that our climate puts onto them. Whereas a brick building (the norm for housing construction) dries out-- the houses on my street are nearly 200 years old (but they are incredibly energy inefficient).

Having built several passive solar houses, there is no need for movie star incomes.
In my experience, keys to low-cost are:
1) Use recycled materials where possible. I built a passive solar studio using almost exclusively wood rescued from construction site dumpsters. In Boulder, we have Resource 2000 which is a construction material recycling yard with prices often 70% below retail.
I just added a layer of insulation in my attic that I got for free from a dumpster I noticed as I was biking by.
2) Simple design means low-cost. Minimize complicated roof-lines, window layouts, wall framing, etc.
3) Fund operations out of income if possible. Better to build as you can afford over a longer time period than to pay lots of interest. This also synergizes well with used materials which can take a while to acquire and stockpile.
4) Many construction tasks are reasonable do-it-yourself jobs. Figure out the difference. Framing, painting, window/insulation installation, trim, concrete are the parts I do myself. I usually hire out electrical, plumbing, drywall.
5) Proper site orientation and window placement add nothing to project cost, but have a major impact on building thermal performance
6) Learn to operate any building for energy efficiency. Manual thermostat setbacks at night or during unoccupied periods, plus using window coverings according to solar gain, along with hot water conservation/setpoint reduction can reduce energy use by up to 50% without any remodel or green building technologies.

IMO, the best move you can make is to properly orient your house or building to take advantage of sunlight - passive solar design, passivhaus, etc. But this almost never happens in commercial construction. Business owners orient their glass to the street and the streets are not laid out with passive solar in mind.

Around 1988, a friend showed me one service station in Cheshire CT that was built into a berm and faced away from the main road. You had to drive in and down to the back of the site to pump gas. I wish I could say it was successful, but it seemed to change owners a lot and the last time I visited Cheshire it wasn't even a service station. Even with signage the store was almost invisible among the usual street-facing gas stations. People are used to seeing if there are pumps open, if the lights are on, etc. as they drive by.

You have more flexibility with a house, but most spec house builders orient large windows to the street for curb appeal, not for consideration of solar gain.

I have the land paid for and some money for a structure.

I like the concept of and it is the most efficient according to the NREL -

But I feel a similar building cold be accomplished with a steel frame and foam insulation on the outside.

Or possibly "cement sip's"

My concern with superinsulation is that it can trap moisture within the walls, and gases inside the house. Some builders solve this with electrically-powered mechanical ventilation, but given what I see elsewhere in the world, I would prefer some sort of ventilation that doesn't rely on the power grid.

The need for mechanical ventilation is very climate and operation dependent.

Relative humidity is so low in Colorado that moisture build-up inside houses is very rarely a problem, not so in the Northeast and Northwest.

The first step for indoor air quality is to avoid introducing contaminants (unvented gas stoves are terrible). Not installing new indoor petrochemical products (carpet, upholstery, cabinet finishes,etc.) does a lot for IAQ too. If the solar gain area is slightly oversized, rather than mechanical venting, simple convection venting by opening a high window on sunny days is quite practical.

I've also been in old houses in Baltimore that simply have a fan in the attic, and no air conditioning. They had high ceilings in each room. They were quite cool, and in a Baltimore July that is saying something!

I'm thinking a lot of these older strategies will be rediscovered.

this has been tackled, the problem of ventilation. In fact, better to have it controlled in a highly insulated house, than the sort of uncontrolled that goes on now.

R2000 homes have been around for 25 years in Canada, and have a pretty good record. I'm not sure if there is an equivalent US standard.

AFAIK you can build one of these without requiring mechanical ventilation.

Not according to this:

R-2000 construction always includes controlled ventilation to maintain good indoor air quality. Every R-2000 home must have a mechanical ventilation system to bring fresh air in from the outside and exhaust stale air to the outside.

Oops, missed it. Mea culpa.

also uses a mechanical system.

If you wanted to do without a mechanical system at all, and you live in a hot-cold (but dry) climate (Rocky Mountains) then a very traditional building design might serve eg as with Moroccan houses.

What's up with a solar powered trash can?????

Earthships for earth covered but these for earth temperred ....

With climate change happening, staying cool is more of a energy issue than staying warm. At least where I am at . But why not try for both

Just saw this article in the NY Times today. It suggests there may be a growing NYC government level awareness of PO issues and housing in NYC:

"The Bloomberg administration, hoping to inspire more imaginative design in working-class housing, intends to turn over one of a dwindling number of large tracts of city-owned land to a development team with an unusual plan — to build a low- and moderate-income housing complex bound together by courtyards and roof gardens that would be used for everything from harvesting rainwater to farming vegetables and fruit."