ICC B1 foundation inspections: footings and walls

How much of the B1 is footings and foundations

ICC's B1 content outline gives the area 16% of the exam. On a 60-question test that is roughly nine or ten questions, and it is split into four topics:

The verbs matter. Nearly every line starts with "verify" or "inspect", so questions describe a situation and ask whether it complies, what is missing or what happens next.

Footings: what you check before the pour

Think of the footing inspection as a short list you run in the same order every time.

1. Soil and plans. The footing is sized for a soil capacity. The inspector checks that the soil on site matches what the plans on file or soils report assumed.
2. Depth. Footings must reach below the frost line for the jurisdiction. The local depth comes from the jurisdiction, so a question that gives a frost depth wants you to compare, not recall.
3. Size and layout. Width and thickness come from tables that depend on the load and the soil. Setbacks are measured from the lot lines on the site plan.
4. Footing drains. Basements and crawl spaces have drain requirements. Know where the drain section sits in your edition so you can confirm when one is required.
5. Materials. Concrete strength and any reinforcement come from the plans and the code.

Questions often hide the failing item in a detail that sounds minor, such as a footing bottom sitting on loose fill or a drain outlet with nowhere to go. Read the whole scenario before choosing.

Stepped footings, piers and columns

Stepped footings handle a sloping site. The outline only asks you to verify that they follow the plans on file or the code, so expect questions about when a step is allowed and what the footing must do at the step. Open your IRC to the footing chapter and tab the stepped footing provision.

Columns and piers get their own 3%. Two ideas come up again and again: the load has to be carried down to a proper support, and the member has to be anchored. Wood in contact with concrete or soil also needs protection against decay and termites. The footing versus foundation wall guide explains the vocabulary if you keep mixing those parts up.

Foundation and basement walls: the 5% most people underprepare

This topic bundles many checks, which makes it good value to study.

• Stem wall height above grade. The wall must rise a minimum distance above the finished grade. Look up the figure for your edition and your wall type.
• Anchor bolts. The sill plate guide covers what the plate is. For the exam, know that bolt size, spacing and embedment are table or section lookups.
• Dampproofing and waterproofing. The outline asks you to verify they are installed where required. The key skill is telling which condition triggers which.
• Unbalanced fill. Backfill heights against a wall are limited by the wall's type and thickness. Questions describe a wall and a fill height and ask whether it is allowed.
• Bracing before backfill. A basement wall that is not yet tied into the floor above can fail under soil pressure. The outline lists bracing before backfill as an inspection point, so be ready to say when backfill must wait.

Where to look in your IRC

Do not memorize page numbers, because they change between the 2021 and 2024 editions. Do this instead:

1. Find the footings and foundations chapter in the table of contents. The chapter guide shows how the chapters map to B1 areas.
2. Tab the footing tables, the foundation wall tables and the anchorage provisions separately.
3. Keep a short list of the section number behind each tab. Tabs must follow ICC's rules, so check them in the tab guide.
4. Confirm your edition before you drill. The 2021 versus 2024 guide lists where sections moved.

A 20-minute foundation drill

Set a timer for two minutes and ask yourself one question: where does my book cover X? Cycle through footing depth, footing width, stepped footings, pier support, anchor bolts, unbalanced fill and dampproofing. If any lookup takes more than 90 seconds, tab it better. Then run a few of them in the lookup drill.

For a reasoning check, give yourself an inspection scenario in your head: "Concrete is scheduled for tomorrow. What do I verify today?" Say the list out loud. If you skip soil, depth, layout and drains, you have found your study gap.

Find out where you stand

Foundations are one of seven outline areas, and your other areas may cost you more points than this one. Take the free 10-question check to see your score by area with no signup, and every answer comes with an explanation that names the section it relies on. If foundations come up as your weakest area, ask Plumb, the study assistant, to explain the questions you miss and show your weakest topics and what to drill next. When you want timed practice exams and a study plan built from your exam date, see the plans.

Sources

• B1 Residential Building Inspector Content Outline, International Code Council: area weights, topic weights and the scope of each topic. Section content is described in general terms only; use your own copy of the IRC for the text.

FAQ

How many B1 questions are about footings and foundations?

The outline gives footings and foundations 16% of the exam. On 60 questions, that is about nine or ten.

Do I need to memorize footing sizes and depths?

No. The B1 is open book, so the skill is finding the right table and reading its conditions. Practice getting to the table in under a minute.

Is the frost line the same everywhere?

No. The local jurisdiction sets the depth that applies, so questions that mention a frost depth expect you to compare the footing against it.

Which IRC edition should I study from?

Use the edition for the exam you book. The edition guide explains how to choose and what changed.