Lowtech Graph lists low-tech options for every need of a home. Here you can compare them, find tutorials to build them, and link them together into a circular system. Why low-tech?

Skid or point-support foundation

Passive · New build only

One of 2 ways to meet this need. Cost, carbon, footprint and rankings are relative to other solutions for the same need, not absolute.

What your site needs

Site tolerant of a raised, non-slab floor

A house that rests on skids or on separate pads instead of being locked to a continuous foundation. When clay soil swells or shrinks, the house is not dragged with it: it sits on top and can be packed back level. It avoids the cracks that moving ground causes in a rigid building.

Cost

Low

Upkeep

Occasional

Skill to build

Basic

Lifespan

25-40 years typical for timber skids/posts near grade; longer if steel or concrete point supports used

Embodied carbon

Low

Space / material use

Low

Output timing

None

Skill to repair

Basic

Regulation (FR example)

Part of the structure or footprint: covered by the building permit (permis de construire) for a new dwelling. Rural sites are additionally constrained by the commune's PLU zoning, outside a constructible zone, a new dwelling is generally refused.

Inputs

none

Outputs

• Hazard protection

Compare the 2 ways to meet this need

Levels are relative to the other options for this need, not absolute. Fewer dots is lighter.

• Skid or point-support foundation (This page)
  Can I use it? Not in a flat · New build only
  What does it cost me? Upfront cost: Low · Skill to build: Basic · Upkeep: Light · Change to daily life: None · Works without the grid: Yes
  Choose it if you want a cheap, light foundation that lets the house ride on moving clay and be packed back level.
• Deep pile / screwed-pile foundation
  Can I use it? Not in a flat · New build only
  What does it cost me? Upfront cost: Medium · Skill to build: Intermediate · Upkeep: None · Change to daily life: None · Works without the grid: Yes
  Choose it if you want the house fixed and level on clay that swells and shrinks, with nothing to re-level afterwards.

Sources

• General light-structure foundation practice (project engineering judgment, not independently sourced)

Limitations of this page

We don’t list sizing or quantities, as the yield of each technique depends on the quality of its build. The catalogue compares options but doesn’t dimension them. Regulatory notes are indicative, with a French example, and need to be confirmed locally.