ADU Construction in South Pasadena
South Pasadena ADUs built on treated sills bolted to engineered footings, with fiber cement siding that holds its shape under hard inland sun.
Pressure-treated Douglas fir goes under every wall of a South Pasadena ADU, bolted straight to the footing, because the sill is the piece that touches concrete and the piece termites and damp reach first. A foam gasket under it stops ground moisture from wicking up. Above it, fiber cement siding holds its shape through hard inland sun and dry wind without the warping or splitting wood boards can show as the temperature swings.
The sill and what it is bolted to
Anchor bolts every few feet, with square plate washers, clamp the sill to the concrete so the wall cannot slide when the ground moves. Pressure-treated lumber is required where wood meets concrete, and its chemicals call for galvanized hardware. At wall ends, hold-downs reach from the frame into the footing with threaded rod, carrying overturning force past the sill entirely. The plywood on each shear wall is nailed to the sill along its whole length, which is how the load reaches those bolts and, through them, the soil.
Plan review in South Pasadena
Construction details for those connections go into the set submitted to the South Pasadena building department, along with the foundation plan and the engineer's calculations. Reviewers compare the hold-down capacities to the forces in the calculations and check setbacks from the side and rear lines. Where the ground is uncertain, the footing size comes from a soils report. We make the corrections asked for, in writing and on the sheets, and inspections then start with the footing, bolts and hold-downs, ahead of any framing.
About our adu construction serviceEverything we do in South Pasadena
ADU Construction in South Pasadena: questions
Where the ground is firm, the unit sits on a concrete slab cast together with its perimeter footing, and softer soil calls for footings dug deeper, or a wood floor raised on concrete stem walls. Either one is drawn with the anchor bolts and hold-down rods at the spacing the engineer sets, so sill and walls lock to it.
The test is the slab edge. When it has real depth and sound concrete, we bolt a treated sill to it and frame the walls. When it is a thin lip, we add footing beneath each shear wall before the sill goes down, and the floor gets a vapor barrier.
Units on one floor, 500 square feet or smaller. Larger and two-story designs are priced on their own after a lot visit. A South Pasadena set from us carries the sill, bolt and hold-down details in full on the structural sheets, where the reviewer reads them.
ADU Construction in other cities
More we build in South Pasadena
Book an inspection in South Pasadena
Describe the house and what it needs. We look at the structure first and send the quote in writing.