Footing / Foundation Height Question

[white01ss]

I live in Kansas and am in the process of getting permits for my 40x40 garage project. Due to elevation requirements (we have a pond a creek close by), I am going to have to do a foundation to get the garage to height, which will be approx 43" high. My plan is to then backfill around it to get the proper grade and do it looks clean.

My question, the city where I live is saying they are going to require a 30" trench footing, even though I am having to pour a 43" foundation and backfill around it. Does this sound correct? Would backfilling against the foundation wall still suffice to keep proper protection against frost?

The ground I am building on is virgin ground, so the contractor was planning on digging down ~12".

I really wasn't planning on having to pour 70"+ of a concrete wall before I can even pour my pad.

I apologize in advance if I am doing a poor job of explaining this.

 

[sleek98]

When we did my 40x50 the majority of it was on flat ground but one side was cut into a small hill (that foundation wall is 48" tall). I am just outside of Kansas City on the Missouri side.

They trenched down 36" for the flat part with no walls, then formed up 2x4 footings for the portion that was going to be 36" below grade. Where I circled is where they transitioned from 36" down to just the 2x4 footings.

 

[white01ss]

When we did my 40x50 the majority of it was on flat ground but one side was cut into a small hill (that foundation wall is 48" tall). I am just outside of Kansas City on the Missouri side.

They trenched down 36" for the flat part with no walls, then formed up 2x4 footings for the portion that was going to be 36" below grade. Where I circled is where they transitioned from 36" down to just the 2x4 footings.

Thank you for sharing. This is exactly what I was looking for perspective and others have done it.

The city is trying to mandate I dig down 30"+ all the way around. I don't have a construction background, but this does not seem logical to me since the foundation will be backfilled. I am trying to determine how far to push the issue.

If this was on flat ground and was not going to be backfilled I have zero issue with doing the trench footing, but where my garage needs to be built up to get it to the proper elevation. I didn't want to have to pour 70" + walls of concrete.