Field note 01
The install detail that decides whether proofing lasts
Pigeons enter at the corner, the jumper-wire notch and the skirt gap — so a proofing job is judged on those three places, not on the long straight runs.
Long runs are easy. Any installer can clip mesh along a straight module edge and photograph it looking tidy. The failure points are the internal corners where an L-shaped Mountain House array steps around a plumbing vent, the notch where a jumper wire crosses the perimeter, and the triangular gap under the bottom skirt.
We cut mesh to each of those shapes rather than bending a single strip and hoping. A pigeon needs roughly two inches of clearance, and it will find two inches on a 40-module array in a single afternoon.
The clip spacing matters too. Spaced too far apart and the mesh bows under Altamont wind pressure, opening a gap along the bottom edge in the first windy week of spring.
Field note 02
Why stainless, and why not the black plastic netting
We install stainless steel mesh because Mountain House rooftops combine full sun, high wind and a wide daily temperature swing, and plastic netting fails on all three.
UV exposure on a south-facing 95391 slope is brutal. Polymer netting becomes brittle, then it tears at the fastening points, and torn netting is worse than no netting because it entangles birds.
Wind is the second factor. This town sits at the mouth of the Altamont corridor and it gets sustained afternoon wind most of the year. Stainless mesh holds its shape under that load; light netting flaps and chafes the module frame.
The mesh gauge is chosen to exclude pigeons and starlings while staying open enough that heat still moves out from behind the modules — the point is to close the cavity to birds, not to insulate your array.
Field note 03
Working around Mountain House roof and array layouts
Almost every 95391 array is rail-mounted over concrete flat tile, which means all proofing work happens from ladder-set positions and the tile field is never walked.
Concrete flat tile carries weight on the headlap and batten line only. Step wrong and you get a hairline crack that leaks quietly for years, so our professionals work from the eave and from staged positions rather than walking the field to the array.
Split-plane arrays are common here — some modules on the front slope facing the street, some on the rear over the patio. Each plane is its own perimeter, and the per-panel price already accounts for staging both.
Two-story village homes with a rear array over a narrow setback are the tightest case. Those need ladder positioning planned before the truck unloads, which is part of why the array is inspected and photographed first.
Field note 04
What you get in writing before the mesh goes on
You get a module count, a per-panel mesh price, a separate cleanup figure based on what is actually under the array, and photos of the cavity before and after.
The module count is the whole quote. At $58 per panel, 16 modules is $928 and 24 is $1,392 — arithmetic you can check yourself, which is deliberate.
Cleanup is quoted separately because it genuinely varies. A first-season pair might be a $200 line; a colony that has bred under an array for four years is a different job, and we would rather show you a photograph than average it into a vague number.
Before-and-after photos are standard. Nobody is climbing up to inspect the underside of their own array, so the documentation is how you verify the corners were actually closed.
