Footing Depth Next To Foundation

I have a deck footing 3 feet from existing basement foundation wall.

How deep should this footing be?

There is more than one answer.
First the footing depth depends on the Frost line in your area.
However if the footing is too close to the home it is likely the soil has previously been disturbed and is not properly compacted. If it is not then you must go down to undisturbed soil.
These are the two simplest answers but there can be more!


Limitation. You can not determine depth the foot extends in the soil by looking at the surface. Width, yes.

Typically/usually/normally in my neck of the woods, sono tubes are buried ‘to the required depth’, below the frost line, in that location.

As for 3’ foot clearance from other footings. No issues from here.

Minnesota Rule-O-Thumb… Footings should be set to the same depth as the home’s footings, regardless of it’s distance from the home. (In SoMN, that would be 6-8 feet deep).

The footing should go below the frost line on undisturbed soil…as indicated.

1 Like

Or solid rock.

Yep, Marcel, if the solid rock goes below the frost line…many up here do not.

I think he meant on ledge Larry where it would not matter if it is above the frost line.
I’ve built hospitals with foundations 2’ down on top of the ledge.

Gotcha… … Thanks.

Depth: below the frostline.

DCA6 Says (note the “must”):

Gee… where have I seen that before??

take it easy boss, had to give others a fair chance to play :slight_smile:

PS: I did send you :+1: & be happy I did not ask about a “footer”!

Geez… where’s that thread about having ‘thick skin’?!

P.S. What’s a ‘footer’?

Skin getting too thick… soon will need a moisturizer :expressionless: Hey Jonas!! can you talk to other fellows on this thread… what’s up with the frostline being good enough?

PS: footer is a special type of a footing :smiley:

42" is the requirement in NJ

For a footing right next to existing house basement foundation or somewhere remotely located? there is a slight difference :slight_smile:

Yeap, thanks for posting the drawings :slight_smile:

Depth and Width of Footings
Depth: Footings should extend to a minimum depth of 12 inches below previously undisturbed soil. …
Width: Footings should have a minimum width of 12 inches.

Where did you get that information?

1 Like