Digging around foundation: Rule of Thumb?
#1
02-26-13, 09:18 AM
Digging around foundation: Rule of Thumb?
Digging down around one wall (the downhill side) of my foundation currently, to create access to the foundation, and prepare a site to break an opening in the foundation for a door.
Is there a rule of thumb on how close to the foundation one can dig before needing to support the foundation given the below soil condition? Is there a rule of thumb on how far deep one can go? Not doing -any- digging under it.
The soil composition is compacted moist clay. The house is a 1 story, 1600 square feet, built in 1930.
Is there a rule of thumb on how close to the foundation one can dig before needing to support the foundation given the below soil condition? Is there a rule of thumb on how far deep one can go? Not doing -any- digging under it.
The soil composition is compacted moist clay. The house is a 1 story, 1600 square feet, built in 1930.
#2
02-26-13, 09:25 AM
Group Moderator
As a general rule I draw a line downward at a 45 degree angle from the bottom corner of the concrete footer and do not disturb the soil within that cone underneath the footer. If the soil is sandy or appears loose I will stay further away but compacted clay is usually quite rigid.
I stay out of the cone area under the bottom of the concrete footing. For extra safety I use 45 degrees which is a shallower angle than shown in this diagram.
I stay out of the cone area under the bottom of the concrete footing. For extra safety I use 45 degrees which is a shallower angle than shown in this diagram.
#3
02-26-13, 09:48 AM
Member
Pilot Dane is correct and I recommend 45 degrees out from the toe of the foundation (footing) since it is always safe and reasonable. This is independent of the foundation wall thickness as long as the footing is reasonably sized. This is commonly used when installing french drains to reduce moisture and improve stability.
Dick
Dick
