How Many Piers Does a House Need?

Every foundation quote is really a pier count wearing a dollar sign. So before you compare bids — or panic at one — it helps to know how the count is honestly derived. The good news: the math is simple enough to do on a napkin.

The rule: affected footage, not house size

Piers don't go around your house; they go under the parts that are moving. The honest formula:

• Step 1: The elevation survey identifies which wall runs are actually low and trending — the affected linear footage.
• Step 2: Divide by 6 (standard spacing, set by what grade beams can span) and round up.
• Step 3: Corner logic: an affected corner needs support on both intersecting walls, with the corner pier shared between them.
• Step 4: Adjustments: two-story sections carry roughly double the load and may need tighter spacing; severe drops sometimes take an extra pier as a lifting point.

Worked examples (typical corridor homes)

• Settled rear corner: 12 ft on the back wall + 12 ft on the side = 24 LF ÷ 6 = 4 spans → 5–6 piers.
• One full side (the dried-out west wall): 48 LF ÷ 6 = 8 spans → 9–10 piers.
• Rear + corner return (the diagram above): 70 LF → about 13 piers, corner shared.

Pair these with per-pier prices from the cost guide and you can sanity-check any bid in your head — which is exactly why we publish both.

Estimate yours in two minutes

The repair calculator runs this exact logic on a sketch of your floorplan: draw the shape, tap the affected walls, and it places piers at 6-foot spacing with the corner rules applied — then shows the math openly, the way a quote should.