Sunday, February 6, 2011

New Concrete or Urbanite?

PG&E has finally begun to respond, and we now have a date of Feb. 28 for the start of the 200 amp upgrade. We began the process in late October, and in November were given a start date of December 24. December 24 came and went, and in early January they began asking the same questions that they were asking us in early November when we started the process, suggesting that someone had forgotten about our application. The Lovely Wife sent a irritated note to the woman in charge and someone else,  who forwarded it to the manager. Now, things seem to be moving along, if still somewhat slowly. We would like to get an earlier start date, since Aerovironment is supposed to come on Feb. 28 to do a site assessment for the electric car charger. The 240V/40 amp circuit needs to be in place and hot by the time Aerovironment shows up. In any case, sometime in the next month  we expect PG&E to have the service at least started.

This week, we began the process by having the concrete removed on the area around the gas and electric meter, where our underground service enters the house, as you can see below:

Because we have underground service, it is not simply a matter of stringing a new wire. We need to have a trench dug, the conduit removed and replaced with a larger one containing a larger cable. However, there are complications. Since our house was built,  the code has changed and now they will not put a breaker panel  directly next to a gas meter where the current one is, probably due to the possibility that a spark from the breaker could ignite a leaking meter, especially during an earthquake. So they need to  move the new breaker panel around 4 feet down the side of the garage,  on the other side of the gate to the back yard. The electrician is coming this week to put in the new breaker panel. He will wire in all the new circuits,  including the three 220V/20 amp circuits for the electric on-demand hot water heater, the circuit for the car charger, and probably a couple of 110V/15 amp circuits, like the new one in the garage where the plug-in converted Prius will be plugged in. That leaves only connecting up the new breaker panel to the main and into the old main panel, which will become a subpanel, for the service upgrade to be complete.

We also want to reroute the rain gutters on the west side of the house so that we do not have two downspouts emptying onto the sidewalk on the west side. They leave a mess there every winter: leaves from our neighbor's Polycarpus trees, gravel from the roof, a wet spot that doesn't go away because the area doesn't get any sun at all, and, to top it all off, green moss that makes the sidewalk slippery. The new design will drain around 2/3 of the roof on that side forward and down a spout on the front next to where the concrete is currently out rather than through two spouts onto the sidewalk. The water will drain out into a narrow strip garden between the driveway and the neighbor's property. The garden will need to be replaced, because it is exactly there that PG&E will be digging the trench.

The removal of the concrete left open the question: what to do about the hole? Our original plan was to simply lift one section of the sidewalk off or have PG&E tunnel under it rather than remove it, but the need to move the breaker panel impacted more of the sidewalk than we had originally anticipated so it had to be removed. To handle the new roof drainage, we had planned to slip a pipe under the sidewalk for the downspout drain. Now, we have to replace a larger section of the sidewalk. We could of course have fresh concrete poured, but cement production has one of the highest green house gas production rates of any product, so avoiding new concrete seemed like a good idea.

Besides, the old concrete is still in good condition. These days, they don't take a jackhammer to concrete when they want to break it up, but use a saw to cut it very precisely. Unlike the concrete in our backyard that we had removed a few years ago to enlarge the garden, this sidewalk didn't have any rebar embedded in it so it was fairly easy to remove and came out in regular pieces as you can see in the following photo:

The pieces look like the concrete pavers we saw at Lyngso Garden Supply last week, just bit thicker and denser. In fact, they look as if they should work quite fine as urbanite, the sort of fancy name people in the green garden trade give to concrete that has been removed, broken up, in some cases dyed, and reset as pavers. One of our neighbors had her backyard redone last year and had her concrete sidewalk broken up into urbanite:

The advantage of urbanite is that the cracks between the slabs allow water to seep in rather than run off as a sheet. This recharges the water in the garden and reduces the load on the city storm drain system. Plus, it looks much nicer than a single slab of concrete.

So our plan now is to reset the concrete slabs as urbanite in gray decomposed granite, and not dye them, since the current color matches the driveway and the rest of the sidewalk. For the water drain, our garden designer, Chris (from Garden Escapes by Chris Todd) recommends a small gravel-filled channel level with the urbanite surface rather than a pipe. This will drain down into a pebble filled faux streambed in the small strip garden where the water can filter in. Chris will be in charge of resetting the paving and redoing the side garden once PG&E is through.


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