Foundation : Random Rubble ; For mud construction

Foundation for natural building

Random Rubble Foundation -A Sturdy Link to the Past and Sustainable Future, But Is it Safe and Reliable?

1. The Big Why:

1. The concept of random rubble foundations can be traced back to ancient civilizations, where skilled craftsmen used locally sourced stones to create strong and resilient bases for their structures. From the magnificent ancient pyramids of Egypt to the grandiose Roman architecture, random rubble foundations stood as a testament to human ingenuity.

1. The strength of the random rubble foundation lies in its seemingly chaotic arrangement of stones. This randomness leads to interlocking stones, creating a monolithic structure that can bear substantial loads. The uneven distribution of pressure ensures that no single point is overloaded, enhancing the foundation's resilience.

1. The flexible nature of the stones allows the foundation to absorb and disperse seismic forces, reducing the risk of structural damage during earthquakes. Moreover, in areas with unstable soil or varying ground conditions, the flexibility of the foundation prevents cracks and shifting, thereby maintaining the building's structural integrity over time.

1. One of the most remarkable aspects of random rubble foundations is their eco-friendliness. The use of locally sourced stones reduces the need for energy-intensive manufacturing processes associated with concrete and bricks. As a result, this foundation style has a significantly lower carbon footprint. Additionally, the absence of mortar or cement between stones allows for better water drainage and prevents moisture-related issues such as mold and mildew growth.

How to build a random rubble foundation

Step 1: Dig Trenches - 1 1/2 or 2 ft deep. The width of the trenches depends on the kind of plinth you are building on top; the width has to be wider than the plinth wall by a few inches. Check the natural slope of the site.

                                              2ft x 2ft trenches dug for super adobe structure

Step 2: Tamp the base and add small coarse aggregate up to 8 inches and level it by tamping more, making sure there is no undulation because it might cause waterlogging and seepage in the future.

Tamping tool used to level the gravel infill

Step 3: Add a French Drain; add big coarse aggregate on top to cover the pipe up to the plinth level, keep tamping the gravel to make sure each level is balanced and filled up correctly.

Random Rubble Foundation