I am a little confused about footings and foundations

According to code can someone explain the requirements on footings and foundations for 1 and 2 story homes.

The way I understand it is a 1 story home must have a footing of 12" wide and at least 12" below the frost line.

A two story home must have a footing of 12" wide and 18" below the frost line.


The soil type may affect the width of the footing. Different soil types will bear differently. Where the house is located (affecting the depth of the frost line) is also a factor. Hope this helps.

You really should list your location in your profile. Most of CA requires footings to be a minimum of 18 inches deep.

Your location is not listed on your website either, nor is a phone number for that matter.

here is a link.
It is dependent upon soil weather zoning but you will get it.
We are not code inspectors remember.


Thanks guys and I know we arnt code inspectors but I have pretty much put all of my eggs into this home inspection business and am very dedicated to being successful and doing a good job.

As of now I could do inspections because in Michigan there is no requirement. However I live near the Indiana border and they do require a license and you have to pass the NHIE test to get it. I am confident in doing inspections now but want to be honest about my credibility and credentials before I start doing them. So as of now I haven’t done any type of marketing or advertising.

I really need to pass this test on the 1st shot and if I dont then I will have to sell more stuff heh. I will read that article from the link and hopefully get a better grasp on the subject =).

Again thanks for the help.

Joining InterNACHI has proven its worth already!


nachi.org/education is a great resource.

In my building and safety departments… there are handouts for typical construction TYPES and Drawings of each, you could pick some up and learn the different requirements for the areas you are to be working in.

You can also find information on the web, go to a new construction site (tricky) and see how different types of foundations are built.

Many portions of the home’s foundation are concealed from view upon inspecting a finished home… you will need to learn to be able to properly inspect and discern other indicators of these items as well the Standards of Practice (ours or your License Boards) that will describe how and what you are looking at. Most cracks mean little…others mean alot… couple this information with other methods.

There is a lot to learn… it’s not an easy way to make a living and you are asking people to trust you with what is likely to be there largest purchase. Learn all you can to do a good job for them, it reflects on you AND our trade!

Good luck!

Excellent post Tim.

Heh thanks Tim!

I think I can do this. I worked in contruction for 8 yrs and learned a lot from that and have always been the guy my family would come to for anything built.

I have my degree in computer science and when I took this on I knew it couldnt be worse than that! lmao

I will say though that at first I thought this would be easier than it is and I can already tell that ongoing education is going to be a staple in my success.

Right now with the way the job market is and nobody going to pay me hardly more than minimum wage as a computer scientist in my area I think I found the right path for myself.


I have built and repaired for over 34 years now.
I am not trying to be smug but, when I look back at my life experience in the field, I was only getting grounded on the singular trade after 10 years.
Its what 3 years of labor first?
2 journeymen trades and 1 apprenticeship with every-other trade mixed in.
I wish you the best mate.

Footings (bottom of excavation) must be at least 12" deep, 6" thick, and must extend below the frost line (not 12" below the frost line). That’s the IRC rule.

The width is based on the load bearing value of the soil and the type of siding and is specified in Table R403.1.

Well Robert construction is similar to home inspections where things change and there is always more to learn.
I agree the first 2 years were doing mostly labor haha!

However the experience in construction has taught me far more than I realized. While taking my courses to learn the home inspection trade I ran into several things that made me think “who doesnt know this!”. I dont think your giving yourself credit for how much you do know compared to the average Joe, let alone your average client.

I bet I was the only computer science graduate in the decade that owned a router not to mention $30,000 in other tools lmao! You ask them and there is no such thing as a router thats used for wood. A router conntects computers to a network!!! haha


I also have a BS in Computer Science. Crawling under houses pays more (or used to). :wink:

Don’t follow this first rule whatsoever. Never seen a 6" thick footing, but what do I know…

What do you mean, “don’t follow”? What is it that you see?

No I as not saying this to imply anything but to show you that it is a never ending learning cycle.
You will be good and that experience will help you excel faster than someone without.
I was just being relative in the experience issues you pointed out.
With me its technical language that I lack.
As to the consumer they know little and that is where your professional, sales, technical language, business entrepreneurial etc skills will be developed with residential building inspections training.
I though it helped but was I in for a surprise ( that’s me ) I am still at it and see it never ending.
Good luck , you will be fine.
YEA !!!

WOW you have a wild website opening.
I did not go in but man its the nicest example I have seen yet.
Meaning excellent graphics mate.
Had to say this so others can have a look.
I see you have 100 post and did not recognize your name.
Not being noisy because I wanted to see the person behind the post.
I have seen 6 inch footings and footers before on bad sites.
That being said…
Dam sight to shallow for me but it is relative to the weight being carried.
Is it not?

I wasnt trying to be harsh with my statement. But there are many factors associated with the size of a footing. I do understand that some see a lot of older houses and with that being said may see things that are not that sound. I havent looked in the code book to see what is written (if there are any specifics) but I can tell you that anything within the last 25 years or so you would be hard pressed to find a 12" x 6"D footing. I have build homes in both the northeast and in FL, both very different building styles but even with that the footing is factored larger and determind by the arcitect and engineer.

Thanks on the website. Check out the About Us page. Not finished yet…

I think with things like this everyone would do themselves good to go watch homes and building being built in their area to see how it is done.

The footing dimensions depend on how many stories the home has, how well the soil is and the frost line depth. My problem was not that I didnt know how it works its more of I didnt know how the stupid test is going to want the answer! =)


David, do not get nervous about the test.
Tests are not stupid, but to judge your level of aptitude on any given subject. You will do fine and I wrote things down and numbered them. Not that the questions will come at you in order of sequence to the chapters but it helped me in my method for memory.
Go over everything once quickly and then go back to the start and do a good review and you will be OK.
Its 4 answers to one question David, you will spot the right one when you see it.