What's better, a poured stone foundation or a block foundation? What are the differences? Tim Carter answers in The Washington Post's ASK THE BUILDER Column. He writes:
The difference between the stone and block is that stone is solid all the way through. The concrete block has void spaces to make them lighter and easier to lay in a wall.
In the early 1900s in the Midwest, the only thing that limited the final shape of the [poured concrete] foundation was the design of the wood forms that held the wet, plastic concrete that was placed in them. Concrete block didn’t require any forms to be built. A block foundation contractor that had enough masons and hod carriers could complete a large foundation in one day. It was a revolutionary building material.
You can build a concrete block foundation that’s stronger and more durable than a poured wall as long as the block foundation has lots of vertical and horizontal steel in it and the void spaces in the concrete block wall are filled with pea-gravel concrete. On the other hand, a poured concrete foundation can be formed and poured on the same day.
At the end of the day, I feel your decision will be based on a cost comparison, but both the concrete block and poured walls need to have the mission-critical steel in them and to be designed correctly so you can compare the real cost between the two. Good luck.