Life At Villa Boswell

A colleague of mine, who is significantly remodeling his house, said to me, "I am continually amazed at how complex this process is turning out to be."  Most people tend to visualize building a house in sweeping "mental gestures" that over-simplify each phase of construction, and I was no exception. It all seems so simple in your mind. This post describes work that was completed by the beginnning of August, 2007.

Clearing the Lot

Let’s start with the lot itself.  As you could see in my earlier post, the very "building envelope" was weird.  But that’s a 2-D view, and if you’re not so good at interpreting ISO contour elevations, this post will give you some idea of the lot.  You can see the easement lane sweeping to the left, and all the Eucalyptus trees in front that had to come out.  The materials in the foreground were supplies that our neighbor had placed there. 

The first thing was to get the materials out of the way and clear the trees. Here you can see the view from the "driveway."

What Does 40% Grade Mean?

The previous photo gives you some idea of how sloping our lot was, but this one really spells it out.  Ooof! Overwhelming, but quite typical of this area, I came to realize later.

Widening the Easement

Part of the lot preparation required by San Mateo county was that we widen the easement.  Here, the photos shows the machine that drilled the piers that would support the initial retaining wall marking the boundary of our lot. The second shot shows the view potential from our house.

Our Contractor

At this point, Chris has quit his job at Brocade Communications and would be working full time on the construction of the house.  These early days in the summer of 2007 were really trying, because every day he had to drive all the way from Pine Cottage in the Santa Cruz Mountains to Half Moon Bay, a 45-minute trip one way.

Main Retaining Wall Complete

The following photos show the completion of the easement retaining wall.  The photo below is the view from the "driveway" and you can see the steel moment frames beginning to be erected.

The stairway from the easement to the main entrance is yet to be poured.  Its molding is on the left.  The completed steel moment frame in the far background shows the basic shape of the narrowest part of the house. 

The photo below shows the structure of the soil of our lot: decomposed granite.  You can see here where one cut for a retaining wall is made.  The wall simply stays in place due to the nature of the granite.  You can also see the pile of rebar used to construct the pier cages.

The photo below shows one of the piers that was drilled for the foundation, along with the form for the 2nd retaining wall.  There were 31 piers altogether, each of which were 18′ deep and 18 inches in diameter.  The soils engineer required that the piers be only 16" in diameter/15 feet deep, but the auger operator only had an 18" auger and to be safe, we made them 18′ deep.  The rebar protruding from the top of the sono tube is part of a big cage of rebar embedded in each pier.  The cage is composed of 8 rods 5/8" in diameter, held together by a spiral of 3/8" rod.

Retaining walls complete

The photo below gives a nice shot of the retaining walls, which were finished with a patterned mold that created a look of stacked  blocks.  Later, we’ll fill the voids left by the mold and use concrete stain to finish the look.

Moment Frames In Place

The photo below shows all the steel moment frames in place, each of which is anchored on one of the 31 piers.  These moment frames had to have full penetration welds for shear strength, and each weld had to be inspected by an independent engineering organization (cha-CHING!) in order to conform to California’s strict seismic requirements.  This house is engineered to withstand an earthquake greater than 8.0.  Given that the soil is decomposed granite, and the piers themselves exceed the requirements set out by the SE, we feel it’s a pretty solid construction.  Additionally, people with older homes who live in the ridge area where our house is located have reported that they hardly felt anything when the Loma Prieta earthquake struck.  This is because the terrain here is bedrock, as opposed to the alluvial soils found in the lower regions.

Foundation Beginnings

The final photo shows how the rest of the foundation of the house will be constructed, tying in the moment frames with yet more rebar, and building forms for each component of the foundation. If we thought it took a lot of time to get to this phase, the construction of the foundation would offer yet another realization of how complex a house like this can be.