What Is a CL-100 Inspection in South Carolina?

Travis Pfeu • November 9, 2026
What Is a CL-100 Inspection in South Carolina?

A CL-100 is the Official South Carolina Wood Infestation Report, a visual inspection for termites, other wood-destroying insects, wood decay and excess moisture that is commonly required before a home sale closes. It must be completed by a pest control business licensed through Clemson University's Department of Pesticide Regulation. When a CL-100 finds damage or moisture, Lowcountry Crawlspaces in Charleston, SC repairs the framing and fixes crawl space moisture. Call 843-259-8194 for a free inspection.

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By Travis Pfeuffer, owner of Lowcountry Crawlspaces · Published November 2026 · Last updated November 2026

A CL-100 is the Official South Carolina Wood Infestation Report, often called a "termite letter," and most South Carolina home sales include one before closing. A licensed pest control company inspects the house for termites, other wood-destroying insects, wood decay and excess moisture, then records what it finds on a standard state form.

If you are buying or selling a home in the Charleston area, here is what the report covers, who can do it, and what happens if it turns up a problem.

What Does CL-100 Stand For, And Who Regulates It?

CL-100 is the form number for the Official South Carolina Wood Infestation Report. The form and the pest control businesses that complete it are regulated by Clemson University's Department of Pesticide Regulation(DPR), which licenses pest control operators in South Carolina.

People use several names for it: CL-100, CL100, termite letter, termite inspection or wood infestation report. They all mean the same document.

Why Is a CL-100 Needed For a Real Estate Closing?

A CL-100 gives the buyer and the lender a record of the wood condition in the house at the time of sale. Many lenders require one, and it is common in South Carolina purchase contracts. Even with a cash purchase, most buyers order one because termite damage is hard to see without crawling under the house.

Timing matters. Lenders and closing attorneys often want a report dated close to closing, commonly within about 30 days. Ask your closing attorney or lender what they need for your loan.

Who Performs A CL-100 Inspection?

A CL-100 must be completed by a pest control business licensed in South Carolina. A general home inspector cannot issue one unless the company also holds the right pest control license from Clemson DPR.

Lowcountry Crawlspaces does not issue CL-100 reports. The inspector writes the letter. We are the company you call when the report finds damage or moisture under the house. See our CL-100 clearance repairs.

What Does a CL-100 Inspector Check?

The inspection is visual. The inspector looks at accessible areas of the house, usually with most of the time spent in the crawl space. They check for:

  • Subterranean termites, live or signs of past activity such as mud tubes.
  • Other wood-destroying insects, such as powderpost beetles.
  • Wood decay (rot) caused by fungi.
  • Excess moisture in the wood and in the crawl space.
  • Visible damage to sills, joists, girders and subfloor.
  • Evidence of past treatment.

The report notes areas the inspector could not reach, such as sections of a crawl space that are too low or blocked.

What a CL-100 is not. A CL-100 is not a structural engineering report and does not tell you how to fix damage. It records what the inspector could see on that day. Hidden damage inside walls or under flooring may not show up.

What Happens If a CL-100 Finds Termites or Damage?

The steps depend on what the report shows and what your contract says. In general:

1

Active infestation

A licensed pest control company treats the house.
2

Damage

A contractor inspects the damaged framing, gives a repair scope and makes the repair. This is where we come in. See our termite damage repair service in Charleston.
3

Negotiation

The buyer and seller agree, under the contract, who pays for treatment and repair. Your agent and closing attorney guide this part.
4

Follow-up

The pest control company may re-inspect or update the report after work is done.

Common repairs after a CL-100 include sistering floor joists, replacing sections of sill plate and replacing damaged subfloor. See crawl space repair. We photograph the damage and can document the work for the closing .

What Happens If a CL-100 Finds Excess Moisture?

Excess moisture on a CL-100 means the crawl space is wet enough to put the wood at risk of decay and insects. Moisture findings are common in the Lowcountry, where humid air and low elevation keep crawl spaces damp.

The fix is to remove the source of the moisture, not only to dry the wood once. Depending on the house, that can mean:

Encapsulation work from Lowcountry Crawlspaces carries warranty coverage that stays with the house when it sells , which can help a buyer feel better about a house that had a moisture finding.

How Can Sellers Get Ahead of a CL-100?

If your home has a crawl space and you plan to sell, a look under the house before you list can surface problems while you still have time to fix them. Repairs are easier to schedule before a buyer and a closing date are waiting on them.

Our inspection is free. We get under the house, take moisture readings and photos, and give you the findings in writing.

More Questions Answered Straight

What is a CL-100 in South Carolina?

A CL-100 is the Official South Carolina Wood Infestation Report, a visual inspection for termites, other wood-destroying insects, wood decay and excess moisture. It is commonly required before a home sale closes.

Who can perform a CL-100 inspection?

Only a pest control business licensed in South Carolina can complete a CL-100. Pest control licensing is handled by Clemson University's Department of Pesticide Regulation.

How long is a CL-100 good for?

Lenders and closing attorneys often want a CL-100 dated close to closing, commonly within about 30 days. Ask your closing attorney or lender what your loan requires.

Who pays for repairs found on a CL-100?

Who pays for CL-100 repairs depends on the purchase contract and what the buyer and seller negotiate. Your real estate agent and closing attorney can explain the terms that apply to your sale.

Does a CL-100 check for moisture?

Yes, a CL-100 checks for excess moisture as well as insects and wood decay. Moisture findings are common in Lowcountry crawl spaces because of the humid climate.

Does Lowcountry Crawlspaces do CL-100 inspections?

No, Lowcountry Crawlspaces repairs the damage and moisture problems a CL-100 finds, but a licensed pest control company issues the report.

Failed a CL-100? We Fix What It Found.

Call 843-259-8194 or book a free inspection. We get under the house, photograph what the report flagged and give you a written scope for the repair.

Call 843-259-8194 Book a Free Inspection

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It’s a smart move for a healthier living environment. What are common signs that my crawl space needs waterproofing? If you're noticing standing water, moldy smells, or rust on metal, it's a clear sign your crawl space might need waterproofing. Don’t ignore these issues to keep your home safe and dry! What are the benefits of installing a vapor barrier in my crawl space? Installing a vapor barrier in your crawl space keeps moisture out, protects your appliances, and helps manage floodwaters, creating a dry and healthy environment. It's a smart step for better home protection! How often should I perform maintenance on my crawl space? It's best to perform crawl space maintenance at least twice a year, checking for moisture and cleaning vents to avoid problems. Keeping on top of this will help protect your home! Why should I hire Lowcountry Crawlspaces for waterproofing services? 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