Until now all the construction effort has been around “building down”, deconstruction, grading, and excavation. The first step in “building up” has been taken, part of the foundation trench has been filled with slurry. Eventually they will build the foundation wall using masonry blocks and their concrete footings on top of the slurry.
Why the trenches and foundation walls? Isn’t the foundation just a concrete slab like all other houses in Southern California? Well, portions of our house will be built on a slab and others on a raised (crawlspace) foundation. A raised foundation requires foundation trenches for the perimeter foundation wall and structural footings. With a raised foundation, plumbing pipes and heating ducts can be accessed via a crawlspace underneath the floors. With a slab foundation, the plumbing is embedded in the slab, buried underneath the slab, or overhead in the ceiling…in all cases disastrous if you have a leak. I’ve also heard that walking on a raised floor is more comfortable than a slab, the raised floor “gives”, hopefully without being creaky. However a raised foundation is more expensive and takes longer to put into place.
So why a raised foundation? Well one of the features of our new house is an engawa (veranda), which requires a raised floor. I’ll talk about the engawa in more detail in a future post.