Posts having to do with sustainable use of materials that don’t fall under energy or water

Come get hands-on, physical and dusty!  Learn about straw bale building while helping us build the straw bale walls for our library. We will be trimming, notching & stacking the straw bales that make the exterior walls of our superinsulated library.  We’ll supply the bales and tools… but bring gloves if you have them.

Kids are welcome, we have a play structure in the back, mounds of dirt, and lots of sharp objects lying around from construction (just kidding, we’ll rake everything up before the bale raising).  We’ll have supervision for the kids in the back and middle yards, and have art projects, and other activities for them to do.  We will, of course, feed you and we’ll all have a big BBQ at the end with plenty of beer!

RSVP with number of adults and kids (with ages) so we can plan food and activities accordingly.

The drawing of the connection between the house greywater/blackwater sewer system and the greywater wetlands. Stamped “Approved for Construction”

The other exciting news from the week merits its own blog entry.


This is EXTREMELY exciting.  As you could have guessed from previous blog entries, (“Grey is Green” and “Landscaping Plans”), we expected that we would be putting in our greywater wetlands system long after we were done with the house because we expected the planning and permitting to take a long time.

But two things happened.  One, is that in June of this year, our Governator signed the “FInding of Emergency for Proposed Building Standards of the Department of Housing and Community Development regarding the 2007 California Plumbing Code (CPC) California Code of Regulations, Title 24, Part 5 (Graywater Standards)”.  Translated from extended legalese, it essentially said: “we’re in an extended drought, there should be no onerous regulatory red tape in the way of people putting in grey water systems, so get on with permitting them!”.  With one stroke of the pen, he changed the permitting climate entirely, and even exempted single source greywater systems from even needing permits.  This is a pretty major sea change in California.  The current emergency regs can be found here. These will be changing rapidly in the next few months as the wrinkles get ironed out.

The other happening was that Catherine went with our builder to meet with the head of the building department at Mountain View City Hall to review the proposed greywater plan prior to submission.  The plan was to walk through what we would be submitting with his department, and make sure we had all the i’s dotted and t’s crossed before submitting so that we would have as complete a package as possible, and so that we could gauge how receptive City Hall was going to be to our plans – that meeting couldn’t have gone better.

He looked at everything, was very interested in the way we had set up the greywater wetlands, reviewed all the details on Catherine’s hand-drawn “linker drawing” between the architectural house plans and the landscape plans, and predicted that we should have “no problem” getting this system permitted.  We walked out wondering “did we hear what we thought we just heard???”

Yes we did.  Two weeks after submitting the plans, they came back stamped “Approved for Construction”

As Nemo and Dory would say: “We did it! We did it! Oh yeah, yeah, yeah!”

We knew from the very beginning that we wanted to go water independent, and that we wanted to plant native California plants, and we wanted a vegetable garden, and we wanted to irrigate the fruit trees with a permitted grey water system which was filtered through a grey water wetlands, and have a stream, and somehow tie this yard in with both the old guest house we were leaving on the property and the new Zen modern architecture, and and and…  See blog posts “Planning for water independence”, “Fresh canvas”, “Grey is green” and “Rainwater cachement”.  Oh yeah, and have a beautiful yard that was inviting for guests to wander in, children to play in, had cool shady spots for those relaxed summer weekend lunches (for those future relaxed summer weekend lunches that one can have when you aren’t building a house!).

But where to start?  Many decisions were going to be driven by the details of the grey water system, and grey water systems that people put in are often pretty bad eyesores… big external piping and storage tanks full of pea gravel.  We wanted the water management to be a beautiful feature of the yard.   We had some sketches and ideas, and had been reading the bewildering California Plumbing Code on grey water systems, but we knew we’d need help.  Catherine was getting very worried that she wouldn’t be able to figure out how to get all the i’s dotted and the t’s crossed to make a permittable grey water system, and while we both had lots of ideas for the yard, no cohesive aesthetic was emerging that we felt would do justice to the house.

Extremely luckily for us, an old childhood friend of Catherine’s, Amy Cupples-Rubiano, is a LEED certified landscape architect extraordinaire with a lot of experience in California native landscaping from huge commercial projects that she had been working on.  We discussed her taking on this “little project” (the scale of our residential project is tiny compared to what she has been doing!), and she offered to do it through her consulting company Green Pad Designs.

We sat down together at the site and talked about all the things we wanted, and from her first sketch, we knew she would push us in some new directions and manage somehow to build all these desires into a cohesive whole – and we just got the final concept and are thrilled.  

Rainwater cachement tank

This week we put in a 9000 gallon rainwater cachement tank. It is quite a business putting in a tank this big. First, a huge hole must be dug, then the tank is brought in (random people on the street asked if it was a submarine…), a huge crane lowers the tank into the hole, and it gets back-filled with pea gravel before you bury it again under some of the dirt that you just excavated just so you can have a big fiberglass lined hole in the ground. Why on earth bother with all of this? In a word: irrigation.

Although you can’t drink it (yet), rainwater collected off the roof can be used for watering the yard and in arid climates, watering lawns and yard plants is more than half of the water consumption in an average household. In the United States, the domestic water consumption is 572L (about 150 gallons) per person per day. Those of us living in a climate where it only rains part of the year — the numbers tend to be higher than average. An efficient house with lower water use appliances can get water use down inside the house, but unless the water monster in the yard is tamed, installing low flush toilets is making just a small dent.

With a 1/3 acre lot, we were looking at a relatively large chunk of land, the needs of which could easily overwhelm any efficiencies we managed in the house. If we left the 3000 sq ft of lawn that had been there, and we watered according to the standard recommendations (1.5 – 2 inches per week in the hottest months, 1 inch per week in spring/fall), over the course of the dry months, we’d apply about 57 inches of water spread out over 9 months to the lawn (keep in mind, we get 15 inches of rainfall in a good year around here). Add that up over the area, and we’d be looking at over 100K gallons of potable domestic water irrigation spread on the grass alone just to keep it green, in other words, 280 gallons a day on average on that lawn – almost 100 gallons a day for each person in our 3 person household.

The solution for us was no lawn. We read up on California native plantings and figured that with a native garden (and our grey water system when in place), we can cut our water usage for the landscaping dramatically. So dramatically, that we thought we might be able to go municipal water independent for our plants… which brings us back to the tank.

That 15 inches of annual precipitation comes in just a few months, but if we catch all the water that comes off 1500 sq ft of roof, that is 1875 cu ft of water, or 14K gallons a year. Since we have a 9K gallon tank, even in a 70% rainfall year like we’ve been having for the last few years, it will still fill the tank. And 9K gallons is enough to keep our non-native fruit trees, our vegetable garden, and our little pond and stream environment watered (we hope!). In years with hot fall months, or late rains, we’ll probably be using municipal water by October or November — but maybe not.

Does it make sense financially? Um… no. At today’s ridiculously low, heavily subsidized water rates, the rainwater we store in that tank isn’t going to save us much money. There are simply no meaningful financial incentives in place to encourage any kind of conservation. You can’t even make back the cost of a low flow toilet in the lifetime of a house. But we decided to do it anyway. California is rapidly running out of water, and the fee structures will have to change if there is ever to be any real conservations solution. In Australia, rainwater cachement is mandated for all new construction, and at some point California will have to grapple with how to solve this problem. If rates go up dramatically, well, then it will look like a good financial investment, but we’re not holding our breath.

Some interesting numbers from a World Bank 2005 report on fresh water:

The US consumption of water for domestic uses is 572L (150 gallons) per day per person.

Our industrial and agricultural use completely dwarf those numbers at 1,980 L/person/day and 1,643 L/person/day respectively (totaling 4,195 L/person/day!)

We have a sustainable 2,350L/person/day available in the US, so 1,850L/person/day of our use is considered unsustainable, or “excess” use.  What is going to happen as we enter a period of unpredictable climate change, and our population keeps growing?

Graywater plan

The PERMITTED grey water system from the Ecohouse in Berkeley! Check them out at

One of the great ironies of building in chronically water short California is that “grey water” (water from sinks and showers and washing machines) and “black water” (water from toilets) are both dumped into the sewers because you are not allowed to do anything else with your grey water.  Never mind that it could be reclaimed for irrigation, or re-used as water in your toilet tank so that you aren’t filling your toilet with what was potable water before you dumped it in the bowl…  in theory, grey water could be re-used, but the code requirements for permitting are so difficult, that for all intents and purposes, grey water systems can’t be built.  There are all kinds of groups like grey water guerrillas who are flying under the radar, but nothing “legit” until the group at the Ecology Center in Berkeley actually designed and built a permitted residential greywater system in 2007 – with that precedent, we are also going to try.

We will be plumbing our house with parallel sewer systems, and bringing our greywater to the edge of the house near the future stream.  Until we get the permit, the greywater goes into the regular sewer like any normal plumbing, but the plan is to build the leach field underneath the stream bed, and have it terminate in a constructed grey water wetlands at the bottom of the stream, and once we have the permit (and we’ve built the leach field), we turn the diverter valve and start watering the wetlands.  We expect that the permitting process will be long, so we are pursuing it separately from the house building, because the wetlands can be built long after the house is done if we have to.

Rolling Sod

Paul and his dad cut the sod and rolled it up.

The back yard behind the guest house (as opposed to the Middle yard) was a large expanse of water greedy grass which we didn’t want to keep at all.  Bill (Mohr, father of Paul) and Paul cut and rolled up the sod, and we found someone who wanted it on Craigslist!  The sod is now the happy play field of some Los Altos toddlers, and our plan is to turn this area into a California native meadow that requires only minimal watering.

Meadow flowers

Meadow flowers

As part of the house build, we will be installing a 9000 gal rainwater cachement tank which will catch the water from our roof, and our plan is to use it to water the yard, and keep all the landscaping municipal water independent.  We have several fruit trees on the property (figs, plums and loquats), and a few almond trees, and we will be bringing our blueberry bushes and dwarf citrus.  The trees plus a vegetable garden will need some water year round, but the meadow grasses are all adapted to dry climates and go dormant in the summer after being a riot of wildflowers in the spring.  Since we will have lots of dirt left over from the excavation for our rainwater cachement tank, we were planning to put in a few undulations in the otherwise rather flat back yard…  of course we’re keeping the yurt and the play structure!

Back of the original house

The back view of the original house

House interior under deconstruction

The house is coming apart!

House skeleton

The back of the house part way through deconstruction. We had Scott’s Demolition deconstructing the house, and these guys were GREAT. Very conscientious and thorough.

We opted to have the house deconstructed, which means taken apart piece by piece.  It is a longer process than simply knocking it over with a bulldozer and dumping it in a land fill, but much of the wood can be saved and the other parts of the house that are re-useable can be salvaged for use in a new house.