Pool Terraces in Somerville, Massachusetts.

The coping is the one line everyone reads, from the water and from the house. We set it dead level to the shell with consistent overhang, and choose thermal bluestone or granite for grip underfoot — matched to the restored Second Empire and Italianate mansions on Spring Hill and Prospect Hill above the city's signature Victorian two- and three-family houses of Somerville so the pool reads as part of the garden, not a hole cut into it.

Seat walls, steps, and planting beds get designed into the surround from the start, whether the property sits in Spring Hill, Prospect Hill, and Ten Hills or anywhere else in town.

Two properties on the same Somerville street can differ by a third in price, and it is almost never the stone. It is access for machines, the base depth clay-rich glacial till capping the drumlins over Cambridge argillite bedrock calls for, how much water has to be managed, and whether existing planting has to be protected while we work.

You get an itemized scope after we walk the property — what is included, what is not, and where the money actually goes. No allowances that quietly become change orders halfway through.

The part nobody photographs: where the pallets sit, where the excavator tracks, and what the property looks like on a Friday afternoon. In Somerville we plan all of that up front and hold the schedule we gave you at the start.

Stone varies wildly pallet to pallet, so we select it ourselves. In Somerville, where the local character runs to restored Second Empire and Italianate mansions on Spring Hill and Prospect Hill above the city's signature Victorian two- and three-family houses, getting the color and cleft right matters more than the grade printed on the invoice.

A pool surround is the hardest-working stone on a Somerville property — wet feet, furniture, chlorine, and a New England freeze-thaw cycle all at once. Because the land here is clay-rich glacial till capping the drumlins over Cambridge argillite bedrock, which drains slowly and demands engineered footings, we excavate to depth and confine a compacted base under the whole terrace, then pitch it so water runs away from the pool shell and the house.

That base is why the coping stays true and the joints stay tight. Pool decks almost always fail at the edges, where backfill settles and nobody confined the base — on a compact grid draped over seven drumlin hills that slope to the Mystic River lowland, that is exactly where we spend the extra day.