Hardscaping in Seattle

Between $18 and $120 per square foot depending which element you mean, and a whole-garden project across several elements usually runs $25,000 to $120,000. The three things that move a quote most here are access for machinery, how steep the ground is, and how much of what is already there has to come out first. We quote fixed and take no deposit, so the number you agree is the number you pay.

It depends on the element and sometimes on the total. A retaining wall is exempt only if it is four feet or lower measured from the bottom of the footing, outside an Environmentally Critical Area, and causing no damage to adjoining property. Paving does not usually need a construction permit but runs into impervious surface limits counted across the whole parcel. The case that catches people is three individually exempt elements crossing a threshold together. We check the parcel once for the whole job.

Because glacial till does not drain. Under most of the city there is a dense hardpan a foot or two down that water sits on rather than passes through, so a patio base built shallow into that ground becomes a reservoir every winter. The fix is a deeper base in free-draining material and an actual route for the water to leave — a drain line to daylight or an approved discharge, not a hopeful fall into a lawn that is already saturated.

A single patio or one wall is typically one to two weeks on site. A multi-element garden runs three to six weeks, and the variable is almost never the visible work — it is excavation, disposal and base building. Access is the other factor: a job a machine can reach moves several times faster than one where everything is barrowed through a side return.