What is Pyrite?

Pyrite testing determines whether the material beneath a home’s concrete slab contains reactive pyrite that could damage the foundation. It typically involves drilling a small hole in the basement floor to collect samples of the underlying backfill, which are then analyzed in a laboratory using the CTQ-M200 standard. The results are used to calculate an IPPG score, indicating the level of risk—from no concern to high risk requiring remediation. In some cases, an engineering report may also be provided for real estate or financing purposes. Most tests take a few hours onsite, with results available within a few days, and typically cost between $400 and $1,200 depending on the scope.

A typical pyrite test takes a few hours on-site. This includes drilling, sampling, and sealing the hole. Lab analysis usually takes a few days to about a week, depending on the lab and service level.

It depends. If the previous test is old (e.g. 10+ years) and you are preparing to sell or refinance, you may want a new report since testing standards and methods have changed. You might also consider a new test if your old report lacks detail. However, it is probably not necessary if the test is recent, completed by a reputable firm, and includes a clear IPPG score with proper documentation.

Yes, the test is moderately noisy since it involves drilling into the floor. However, drilling typically lasts no more than 15–30 minutes. Most firms can schedule the work at a convenient time if noise is a concern.

There is no official expiration, but reports are generally considered reliable for 5–10 years, or until testing standards change. For real estate transactions, lenders and buyers often prefer more recent tests (within 3–5 years).

Yes. The drilled hole is typically sealed with concrete or patching material. The finish may be basic (functional) or more refined depending on the company. You should confirm in advance if cosmetic finishing is included.

The PSPI (Potential Swelling Potential Index) measures the potential for swelling in the backfill. Lower scores indicate minimal risk, while higher scores suggest increased risk and possible need for remediation.

PSPI Range	Risk Level	With Sulfation	Likely IPPG
0–10	Safe	None	IPPG 0–1
10–20	Moderate	None	IPPG 1–2
15–25+	Moderate–High	Present	IPPG 2–3
20+	High	Present	IPPG 3

Some dust is generated during drilling, but reputable companies use dust control methods to keep the impact localized and temporary. There should be no long-term pollution or contamination.

You can request that the company drill in an unfinished or less visible area, such as a utility room. Placement should always be discussed before the test begins to avoid surprises.