Foundation questions, answered

Nobody can tell from a photo, including us. Engineers classify damage by crack width and ease of repair, and put the key line between slight and moderate at around 5 mm, or several cracks over 3 mm. Whether a crack is changing matters more than any single measurement. See which foundation cracks matter.

Not on its own. We could not trace the popular vertical, diagonal and horizontal rule to any code, standard or engineering society; every source was contractor marketing. A horizontal crack in a wall that is also bowing inward is serious, but the bowing is what makes it so. See bowing wall repair.

Start measuring. Photograph each crack beside a ruler with a dated note, mark its ends, and begin an elevation log. Two readings months apart are worth more than one alarming photo, and they cost nothing. Then check where your downspouts discharge.

Settlement is the structure sinking; heave is swelling soil pushing part of it up. They crack walls in similar ways but are corrected in opposite directions, so a wrong diagnosis buys a repair that misses the problem. Piers do not fix heave. See why foundations move.

It depends on the species and its mature height. The only quantified standard we found is British: 1.0 to 1.25 times mature height for high-water-demand trees such as oak, willow, poplar and elm, 0.5 to 0.75 for other broadleaves, and 0.2 to 0.5 for low-demand species. The US has no code equivalent.

We cannot confirm it. The claim and its “$2.3 billion a year” figure trace to a three-page 1973 article in a professional membership magazine, in 1973 dollars, with no retrievable method. Later figures echo the same source, and the newest is 34 years old. We publish none of them.

Get the engineer first if real movement is suspected. An engineer you hire and pay directly has no stake in the pier count, and the report becomes the one document every contractor bids against. Without it you get three diagnoses at three prices. See do I need a structural engineer.

Yes, if you treat it as what it is: a sales visit, which can be entirely honest. The inspector works for the company that would be paid for the repair. That describes an incentive, not a motive, and it means two free inspections are two sales visits, not two opinions.

Almost always because the bids cover different work: a different method, pier count, assumed depth or set of inclusions. An independent engineer’s specified scope removes that gap. Once every contractor prices the same scope, the differences mean something. See choosing a foundation contractor.

It depends on the state. California licenses it through a pile driving and pressure foundation jacking classification. Texas has no state license for it; the state licenses air-conditioning contractors, electricians and water-well drillers, but not the person who lifts your house. Where no license exists, an independent engineer’s specification is the real quality check.

It depends on the house, which is why we publish no national average.

A drainage correction and a piering scheme can both fit the same cracks and differ by more than an order of magnitude.

Depth to bearing alone can double a job from one lot to the next. See what drives foundation repair cost.

Sometimes partly, rarely completely, and it is a separate decision from stabilizing. With push piers and pressed pilings, the lift is capped by the weight of your own house. Lifting also reverses stresses in a settled structure, so cracked finishes and broken plumbing are real risks. Many engineers advise stabilizing and accepting the current position.

No. A push pier evaluation report states that pile-soil interaction “is outside the scope of this report.” It covers the steel, bracket and connection, not whether the pier holds in your ground, and excludes pier settlement and footing suitability. No ICC-ES acceptance criteria exist for basement wall anchors. See foundation repair methods.

At least 6 inches of fall within the first 10 feet, under the base residential code. Separately, patios, driveways and other hard surfaces within 10 feet should slope at least 2 percent away. Those are two numbers for two surfaces. See foundation drainage and grading.

No. The code treats them as separate requirements. Damp-proofing is the baseline for below-grade walls; waterproofing replaces it where a high water table or other severe soil-water conditions are known. The code does not use the phrase “hydrostatic pressure” there. See basement waterproofing.

Either can be legal, but you cannot casually switch. A vented crawl space is designed around a ventilation ratio. A sealed one needs a detailed vapor retarder plus mechanical exhaust or conditioned air. Closing the vents on a vented crawl gives you neither. See crawl space repair.

Usually not. Standard policies exclude earth movement and the settling, cracking and bulging of foundations, and the exclusion attaches to the cause, not the crack. If a covered peril causes the movement, the damage can be covered. See does insurance cover foundation damage.

Generally no. Homeowners policies exclude below-ground seepage and water pressure through earth-movement and maintenance exclusions. Flood policies exclude them through seepage clauses and need an area-wide event covering two or more acres or two or more properties. This sits between two policies, so treat drainage as maintenance you fund.

No. Florida makes catastrophic ground cover collapse coverage mandatory and sinkhole coverage optional, for extra premium. The mandatory cover requires abrupt collapse, a visible depression, structural damage, and the home being condemned and ordered vacated. Settling or cracking alone does not qualify.

Less than most people assume. The FTC’s own rule indicates federal warranty law does not reach work built into a home or a repairer’s workmanship warranty, so the contract may be your only protection. The FTC also notes “lifetime” has at least three meanings. See foundation repair warranties.

Yes, in at least one state. In 2013 the Supreme Court of Texas held that the implied warranty of good and workmanlike repair can be superseded by an agreement describing the manner or quality of the work. A document sold as extra protection displaced a stronger one. Read what your warranty replaces.

Usually yes. The FTC Cooling-Off Rule covers sales of $25 or more at your home, including visits made at your invitation, so calling for a free inspection does not remove it. You have until midnight of the third business day, and Saturdays count. Several states go further.

No. HyreFoundation is an independent information site that is building a way to connect homeowners with foundation professionals. We do not inspect houses, write engineering reports, install piers, lift slabs or waterproof basements. See about HyreFoundation.

No. We publish no company profiles, rankings or star ratings, and will not until we hold something that justifies them. A directory listing is not verification. How we vet foundation professionals lists exactly what we check and what we cannot.