What Is a CL-100 Inspection?
A Columbia, SC Homebuyer’s Complete Guide

What the CL-100 Actually Is

The CL-100 is South Carolina’s Official Wood Infestation Report — the document a licensed pest control professional issues after inspecting a property for wood-destroying organisms and moisture conditions. The form, the inspection standards, and the licensing requirements are all governed by S.C. Code Regs. § 27-1085, administered by the Department of Pesticide Regulation at Clemson University. Only a technician currently licensed in Category 7A — Industrial, Institutional, Structural, and Health-Related Pest Control — can issue a legally valid CL-100 in South Carolina.

You’ll hear people call it a “termite letter,” but that name undersells what the report actually covers. Termites are part of it, but the inspector is looking at a broader picture of wood-destroying threats that could affect the structural integrity of the home you’re about to buy.

What the Inspector Is Looking For

A CL-100 inspection covers six categories of wood-destroying organisms: subterranean termites (including Formosan), drywood termites, old house borers, powder post beetles, carpenter ants, and carpenter bees. It also covers wood-destroying fungi — the kind that takes hold when wood gets wet and stays wet.

On the moisture side, the inspector takes moisture readings throughout the crawlspace and accessible substructure. The regulation sets two thresholds that trigger required reporting. Moisture content at or above 20% constitutes excessive moisture conditions and must be noted, even if no fungi are visibly present. At 28% or higher, wood-decay fungi become active and structural damage begins to occur — that’s a more serious finding that typically requires remediation before closing.

The inspection covers all accessible areas below the first living floor: the crawlspace, substructure framing, foundation elements, lower exterior doors, door jambs, steps, and porch columns. Upper siding, fascia, trim, and roof areas are outside the scope. So is anything hidden behind wall coverings, insulation, or stored belongings — the report reflects what the inspector can physically see and probe on the day of the inspection, nothing more.

Who Orders It and Who Pays

In South Carolina, either party can technically order the CL-100, and the purchase contract determines who pays. In practice, sellers frequently order and pay for it — especially on VA transactions, where the historical convention was that the buyer couldn’t pay for the pest inspection. That changed in June 2022, when VA Circular 26-22-11 was issued, allowing veterans to pay for the wood-destroying pest inspection when it’s required as part of their loan.

Speaking of VA loans: if you’re buying with a VA loan in South Carolina, a CL-100 is mandatory. The VA’s official local requirements classify South Carolina as requiring wood-destroying insect documentation statewide because the entire state sits in the highest termite risk category. There are no county-by-county exceptions. If you’re financing through VA, the inspection has to happen, and if active infestation or structural damage is found, it has to be addressed before closing.

FHA loans work similarly in practice. FHA doesn’t mandate a pest inspection on every property, but requires one when the appraiser spots evidence of infestation, when it’s standard practice in the area, or at the lender’s discretion. Given South Carolina’s termite risk classification and the CL-100’s status as a standard closing requirement here, FHA lenders in the Columbia market almost universally require them.

The volume of VA loan activity in this market is significant. Fort Jackson — the Army’s largest Initial Entry Training center, right in the heart of Columbia — brings a permanent military community of approximately 3,500 active-duty personnel and 12,000 family members into the local housing market. Richland County ranked 45th nationally for VA loan volume in FY 2019, putting it alongside military markets far larger than Columbia, and VA loan volume in South Carolina grew over 16% from Q4 2023 to Q4 2024. If you’re a veteran buying here or selling to one, the CL-100 is a required piece of your transaction.

The 30-Day Window and Your Closing Timeline

The CL-100 is valid for 30 days. That language appears at the top of the official form itself, and the standard South Carolina residential purchase contract (SCR Form 310) reinforces it — requiring that the CL-100 be dated no more than 30 calendar days before closing. If your transaction takes longer than expected, or if the first inspection turns up findings that require remediation and re-inspection, the 30-day clock can create scheduling pressure. Schedule the inspection early enough that you have time to address findings without backing against your closing date.

When the CL-100 Comes Back With Problems

This is what most buyers are actually worried about, and the good news is that the SC Association of Realtors contract (SCR Form 310) gives you a clear framework when findings are adverse.

The contract’s default position is that the seller is responsible for remedying any active infestations and damage documented in the report. The seller must either provide an updated, clear CL-100 showing the property is free from infestation and damage, or supply documentation confirming that treatment and repairs were completed in a workmanlike manner before closing.

If the seller refuses to address the findings, the buyer has three options: proceed with the purchase as-is, negotiate with the seller for a price reduction or repair credit, or terminate the contract using SCR Form 313 — with full earnest money returned, because the seller’s refusal to perform constitutes a breach of contract. You don’t lose your deposit because the seller won’t fix a termite problem.

When findings require significant repairs that can’t be completed before the closing date, parties can use a repair escrow arrangement — the sale closes on schedule, but funds (typically 1.5 times the estimated repair costs) are held by the closing attorney until the work is done. It’s a practical solution that keeps transactions moving without letting a seller off the hook.

Why Columbia, SC Has Higher Termite Risk Than Most Markets

South Carolina sits in Termite Infestation Probability Zone #1 — the highest of four risk classifications, covering states with “very heavy” termite pressure. That’s not a local marketing claim; it’s the classification used by HUD for federal lending purposes.

What makes the Columbia market particularly significant right now is the confirmed expansion of Formosan subterranean termites into Richland and Lexington counties. According to Clemson University’s Home & Garden Information Center, Formosan termites have now been documented in 16 South Carolina counties, with both Richland and Lexington on that list. Formosan termites were first confirmed in Lexington County in 2018, more than 100 miles inland from where the species had been established for decades along the coast.

The distinction matters because a Formosan colony can contain one million or more workers — roughly ten times the size of a native Eastern subterranean termite colony. That means dramatically faster damage when a colony establishes itself in a home’s structure. Buying a home in Columbia without a current CL-100 is a different kind of risk than it would be buying in a state where the termite pressure is lower. The South Carolina climate — hot, humid summers, mild winters, and the clay-heavy soils common in the Midlands — creates conditions where subterranean termites thrive year-round, with limited population die-off in winter.

Why You Should Order Your Own CL-100, Not the Seller’s

The Department of Pesticide Regulation at Clemson University prints this recommendation directly on the official CL-100 form: the purchaser of the structure, rather than the seller, should obtain the Wood Infestation Report.

The reasoning is straightforward. When the buyer orders the report, the pest control operator’s obligation is clearly framed as full disclosure — reporting everything visible and accessible. When the seller orders and pays for the report, an inherent tension exists, even if unintentional. The seller has a financial interest in a clean report; the inspector is being paid by the seller. There’s no suggestion of widespread misconduct, but the buyer who orders their own inspection has a direct contractual relationship with the inspector and a stronger legal footing if something is missed.

There’s a disclosure gap worth knowing about: South Carolina does not require sellers to disclose prior termite damage that has already been repaired. A home could have had significant termite damage repaired years ago, and the Seller’s Disclosure Statement doesn’t require that history to appear. The only way to know whether prior repairs were done properly — and whether the property is currently clear — is to have an independent inspector evaluate it yourself.