Thursday, October 28, 2010

Landscape Construction -- Interlocking pavers

The interlocking paver project in Landscape Construction was a great team effort.

We started with a design that we developed collaboratively starting with the idea of using a diagonal element and maintaining symmetry. From this we puzzled out several design challenges to maintain balance, not have it get too busy, not have to many cases were seems lined up in a way that was unappealing, etc. Where we needed a half-paver we just placed one on end in the design to mark the spot. When we had something we all liked, we took some photos to record the design for later.

The first step (since the sod was kindly already removed for us) was to determine our excavation depth and start digging. The depth calculation was a little tricky since we wanted
excavation depth = 4" bed + 7/8 " sand + 2 3/8" paver - 1/8" settling - 1" proud
The last term reflecting the fact that (especially in Oregon) we want the finish grade of the path to end up an inch above the surrounding grade. This keeps things high and dry.

We next put in the geotextile fabric to keep our gravel bed from mingling with the subsoil. Ew.

A little thought went into how much fabric we needed to make sure we had enough to keep the gravel in the sides of the excavation.

The gravel went in in three lifts. We used the plate compactor and some hand tamping after each lift. The third lift was required because of the settling that occurred through compaction.

We laid out a 3-4-5 right triangle to give us a good right angle for staking two sides of the edge restraint in place. After this, we laid down 7/8" screed rails to level our bedding sand with the screed board (which was just another piece of edge restraint).

Once we had a sand bed we liked we reassembled our paver design, with the half-pavers cut on the paver saw with a diamond blade.

Transferring the pavers onto the sand beg was very satisfying. We worked from one corner towards the opposite. A few taps of attitude adjustment from the rubber mallet were needed to keep the pavers in line.

We swept in joint sand and used the plate compactor to settle it in.

Looked good in the end.

High fives were had by all.

1 comment:

  1. Looks like you guys did a good job. I'm really looking forward to our brick path to the front porch!