What began as an ambitious plan to remodel and expand the main home quickly shifted focus to stabilizing the existing structure, which is located in a designated high liquefaction zone. In such zones, the soil can lose its strength and behave like a liquid during an earthquake, posing serious risks to structural integrity.

To address this, we are installing 27 helical piers, each extending approximately 13.5 feet deep, to support and stabilize the existing home. The house had experienced significant settlement over time, with the rear portion sitting more than four inches lower than the front. In addition, the house consistently had issues with doors and windows sticking, making them difficult to open and close.

Due to the need to reallocate a substantial portion of the budget to this critical structural work, the scope of the project evolved. Instead, we pivoted to adding a 715-square-foot attached ADU, featuring 2 bedrooms and 1.5 baths, to serve as living space for the homeowner’s extended family. The new ADU will also require the support of 9 helical piers.

Breaking ground for our new 715 square foot attached ADU.

A trench has been dug around the existing house. Helical piers will be inserted periodically into the trench & then capped with a concrete grade beam which will then tie into the existing house foundation. This new structural system will stabilize the existing house & minimize any new future settlement.

Helical piers have been delivered to site. While manufacturers offer various lengths, our contractor elected to bring in 7-foot helicals. Multiple piers will be tied together to achieve the required depth.

The helical piers are similar to a big screw & will be mechanically turned and sunk into the ground.

Tremendous progress has been made on our attached ADU as all the exterior walls have been framed & windows have been installed.

We are currently awaiting the arrival of our roof trusses, which will enable us to accelerate the roof framing timeline by approximately 25–50% compared to conventional stick framing methods.

We appreciate the contractor’s diligence in putting down a sill sealer, also known as a sill gasket, which is a foam strip placed under the exterior wall sill plate to reduce air leakage and moisture infiltration, thereby improving energy efficiency and preventing potential issues like rot.