AAC Blocks (Better than Hollow Blocks?)

What is AAC?

“Autoclaved Aerated Concrete”. It looks like a white pumice stone. It floats on water. (Seriously). It’s like a concrete sponge.

Why use it?

1. It’s Light. Your structural load decreases. 2. It insulates. Better than hollow blocks, but not as good as ICF. 3. It’s Fireproof. You can attack it with a flamethrower and it won’t care.

The “Gotcha”

Moisture. It’s a sponge. It loves water. In the Philippines (humidity 90%?), this is a potential problem. You need SPECIAL plaster (“skim coat”) designed for AAC. If you use regular cement plaster? It might crack or peel off because the block sucks the water out of the plaster too fast.

Earthquake Safety?

Yes. Lighter building = less force during an earthquake. But you still need columns and beams. You can’t just glue the blocks together and hope for the best.

My take

Great for interior walls. Great for upper floors (to save weight). For exterior walls near the beach? I prefer solid concrete or high-psi hollow blocks. I don’t trust the “sponge” next to the ocean.