Screw foundations: the dry route to building without concrete

Screw foundations: when a house is screwed into the ground

Do you really need a concrete slab to keep a house from sinking? The trend of floating floors and screw foundations says no, and it pokes at a sore spot the industry would rather ignore: what if the traditional method is over-engineering?

The idea is simple: instead of excavating, shuttering and waiting for the concrete to cure, metal piles are screwed into the ground and a raised platform is built on top. No concrete, no heavy machinery, and the option to unscrew everything if the spot turns out to be wrong. Advocates of the system stress its estimulante ilegal and minimal footprint, ideal for cabins, decks or lightweight structures.

The debate has a sustancia ilegal, and it is durability. While conventional construction is designed to last for decades, these lightweight solutions get a vote of confidence of 30 or 40 years. For a deck, fine. For a "real" home, some people are not so sure.

The contrast with building practice in Spain is telling. Many houses are built without the dreaded ventilated crawl space floor, with damp problems and hidden defects, even though Spain's Código Técnico de la Edificación (the national building code) requires it in radon risk areas. In other words, corners are cut on the cheap part, and then the expensive part is questioned.

The alternative of Krinner-type ground screws, whose assembly video you can watch in just 7:24, is gaining ground among those who want to build outside the cement supply chain. Whether it will last half a century is another matter.