Tofu Blocks

Mar 12

Why Your Post-and-Pier Home is a Hidden Gem

If you live in a classic Hawaii home, you’ve probably peeked under the house and seen them: the humble tofu blocks. Known as post-and-pier construction, these concrete blocks have been the foundation of choice for island homes for over a century.

While modern developers love a concrete slab-on-grade, there is a reason so many of our historic homes are still standing strong on their tofu blocks. If you know how to maintain them, a post-and-pier foundation is actually one of the most practical and forgiving ways to build on Hawaii’s volatile terrain.

The Secret Advantage: Flexibility vs. Rigidity

Why is post-and-pier often better than a slab for Hawaii?

The Settling Solution: Red dirt is expansive—it swells when it rains and shrinks when it’s dry. When a concrete slab settles or the ground shifts, the slab cracks, and you’re looking at a massive, expensive repair. With tofu blocks, if the house shifts, we can simply jack up the specific area and shim the post. It’s a surgical fix instead of a structural nightmare.
The Airflow Factor: Elevating the house allows our trade winds to flow under the home. This naturally cools the floor and prevents the moisture buildup that leads to mold and wood rot.
Easier Upgrades: Need to move a bathroom or rewire the kitchen? In a slab home, you’re breaking out the jackhammer. In a post-and-pier home, we just crawl underneath.

Things to Look Out For

Metal barrier: In a perfect world, there should be a metal termite shield between the concrete block and the wooden post.
Leaning Piers: Over decades, a block can sink or tilt (differential settlement). If the pier isn't level, the weight of your house isn't being distributed correctly. This is usually why your kitchen door suddenly won't latch or a closet door won’t slide.
Spalling Concrete: The rebar inside older concrete blocks can rust and expand, causing the tofu block to crumble.

FIXIT Checkup

At FIXIT, we don't just look at the blocks; we look at the whole under-story of your home.

Leveling & Shimming: If your house has the plantation lean, we use specialized jacks to gently lift the beams and install rot-resistant shims to get everything back to level.
Clearing the Highway: We ensure there is a clear air gap between the soil and your wood. We’ll remove old debris, trim back vegetation, and check the integrity of your termite shields.
Post Replacement: If a post has been compromised by termites or dry rot, we can replace individual posts without disturbing the rest of the house.
Moisture Control: We check for water under the house. If your gutters or AC condensates are dumping water right next to a pier, that block is going to sink. We redirect the water to keep the tofu blocks on solid ground.