Sammamish sits on a plateau above Lake Sammamish, and most of it was built out as subdivisions in the last thirty years. Under a thin layer of topsoil is glacial till, a hardpan that water barely soaks into, and many lots back onto tall stands of Douglas fir. Shade pavers grow a film. The base still has to be honest, and the surface has to shed, or that film is a slick coating on a puddle.
King County · ZIP 98074
Pavers that will be wet and green
We do not promise a bright, dry patio under a cedar. We promise one that does not settle and does not pitch at the house. Joints stay filled so weeds and moss have less soil to work with. You will still wash it.
Roots are the other constraint. We do not excavate a base through a main root and then act surprised when the tree declines or the patio lifts. The patio moves, or it gets smaller.
The ground in Sammamish
The till is the reason so many yards here stay soggy in winter and dry out fast in summer. Water sits on top of the hardpan, so a new lawn or patio needs drainage planned in from the start. We put in French drains, grade the yard away from the house, and build patio bases deep enough that they do not heave.
Many neighborhoods have HOA rules for fences, front yards, and plant choices, and we work to those standards. Lots along the greenbelts get heavy shade and needle drop, so we use shade-tolerant planting and bark where grass has given up. Larger backyards here are a good fit for a full redesign: a paver patio, a low retaining wall to level the slope, and irrigation on a timer for the dry months.
How we do the work
The paver is the skin. The base is the job: excavated, built up in compacted rock, deep enough that this climate will not heave it into waves. We pitch the surface away from the house, we restrain the edges so the field cannot spread, and we sand the joints.
A paver patio set on a couple of inches of loose gravel over clay will look perfect in September and rock underfoot by March. We do not build that, even if the other bid did.
What we look at first
- How the water leaves the surface today
- Clay, fill, or roots under the area
- Edge restraint and where the field ends
- Whether the project is a walk, a patio, or a drive, because the base changes
Joint sand
Swept and settled, then checked. Polymeric sand has a place where ants and heavy rain empty the joints, and it has a failure mode if it is installed wet or left on the face. We use it when it helps, and we wash the haze off before we leave.
The base depth
Deeper for a drive than for a walk, and deeper on clay than the brochure drawn for a dry state. We compact in lifts. A single dumped pile of gravel, raked once, is not a base. You should not see waves after the first winter.
Edges
Plastic or metal restraint, spiked into the compacted base, then buried so you see paver, not a black strip. An edge against soil with no restraint is the row that opens up.
More from this crew
- Paver installation across the region
- Patio installation in Sammamish
- Hardscaping in Sammamish
- Gravel installation in Sammamish
- Pressure washing in Sammamish
- Paver installation in Mercer Island
Sources for the climate and the water
- USDA plant hardiness map for choosing plants that can take a King County winter.
- EPA WaterSense on watering less once a lawn or a new planting is established.
- EPA Soak Up the Rain on keeping roof and yard water from becoming someone else’s problem.
