What are common NHIE exam mistakes on anchorage & lateral connections?

Assuming anchorage exists because the house is old and 'has survived.' The fix: Pre-modern homes often have zero bolts — look for heads/nuts along the sill in the crawl; absence is the finding. Counting diagonal let-in braces as cripple-wall shear. The fix: Racking resistance comes from structural panel sheathing — let-ins alone are the pre-retrofit condition. One-size-fits-all lateral reporting. The fix: Emphasize seismic anchorage in quake zones, uplift connectors in wind country — the hazard picks the checklist.

How long does this lesson take?

About 11 minutes to read, plus a ten-question check in the free course.

Anchorage & Lateral Connections

~11 min read · Check anchor bolts, shear transfer and seismic/wind hardware the way the exam expects.

Gravity is only half the load story: wind and earthquakes push sideways, and the lateral system — anchor bolts, shear panels, connectors, and braced cripple walls — is what keeps the house on its foundation. The stable number: bolts at 6 feet on center, within 12 inches of plate ends.

Anchorage

The sill plate bolts the structure to the foundation: anchor bolts at maximum 6 feet on center, with a bolt within 12 inches of each plate end and at corners/splices; nuts and washers present and snug (modern seismic practice wants plate washers). Findings: missing bolts (older homes — pre-anchorage construction simply sits by gravity), corroded or nutless bolts, and retrofit anchors (expansion/epoxy or foundation plates) noted as upgrades. Unbolted houses slide off foundations in earthquakes — the retrofit with the best cost-benefit in seismic country.

6 ft o.c., 12 in from plate ends — the stable rule
Nuts, washers, and corrosion checks
Unanchored older sills = the classic seismic finding

Shear elements

Cripple walls (short stud walls between foundation and floor) fail by racking — unbraced ones collapse sideways in quakes; bracing means structural panel sheathing (plywood/OSB), not diagonal let-ins alone; probe the crawl to see it. Shear walls and bracing in the main structure hide behind finishes — read distress instead: racked openings, diagonal cracking. Garage door walls with living space above (soft-story geometry) concentrate lateral weakness at the big hole. Wind country adds uplift connectors: hurricane clips/straps tying rafters to walls, straps at wall-to-wall and wall-to-foundation — the continuous load path DOWNWARD for wind trying to lift the roof.

Unbraced cripple walls: the quake collapse mechanism
Soft-story garage fronts concentrate weakness
Hurricane clips/straps = uplift path in wind country

Reading and reporting

The inspector reports what is visible where accessible: anchorage presence/spacing sampled in the crawl, cripple-wall bracing, connector hardware, and evidence of movement (slid plates, cracked stucco lines at the base). Framing is climate-appropriate: seismic-zone reports emphasize anchorage and cripple bracing; wind-zone reports emphasize uplift ties. Retrofit recommendations are common-sense referrals — evaluation by qualified contractors/engineers for houses predating modern anchorage.

Worked example

A 1935 bungalow in earthquake country: the crawl reveals a sill sitting on the stem wall with NO anchor bolts visible along 30 feet; 3-foot cripple walls carry only horizontal 1× skip sheathing; and the water heater stands unstrapped beside the furnace. Prioritize the lateral findings.

Textbook pre-retrofit house. (1) Unanchored sill: nothing but gravity connects house to foundation — in ground shaking the structure can slide off; report as the primary seismic vulnerability with retrofit-evaluation referral (expansion/epoxy bolts or foundation plates at the 6-ft/12-in pattern). (2) Unbraced cripple walls: skip sheathing provides no shear resistance — the walls rack and the house pancakes onto the crawl; plywood bracing is the standard companion retrofit. (3) The unstrapped water heater: a tip-over gas-line/fire risk (state-level strapping rules exist for exactly this) — note the restraint principle. Order matters: bolts and bracing protect the structure; the strap protects against the fire after. One era, one finding family, one referral.

Common exam pitfalls

Assuming anchorage exists because the house is old and 'has survived.'

Pre-modern homes often have zero bolts — look for heads/nuts along the sill in the crawl; absence is the finding.

Counting diagonal let-in braces as cripple-wall shear.

Racking resistance comes from structural panel sheathing — let-ins alone are the pre-retrofit condition.

One-size-fits-all lateral reporting.

Emphasize seismic anchorage in quake zones, uplift connectors in wind country — the hazard picks the checklist.

Bolt it down, panel the shorts, strap the roof — sideways loads win wherever the chain has a gap.

Recap

Anchor bolts: 6 ft o.c., within 12 in of plate ends, nuts/washers
Unanchored sills and unbraced cripple walls: the seismic pair
Panel sheathing = cripple bracing; let-ins don't count
Soft-story garage walls concentrate weakness
Wind zones: clips and straps form the uplift path
Report visible hardware + movement evidence; refer retrofits

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