Borate treatments, moisture control, and structural repair under one roof
Crawl Space Termite Treatment McLean VA That Stops Damage Cold
Crawl Space Termite Treatment McLean VA is how you end an active subterranean termite colony before it eats through your floor joists. We inspect the whole crawl space, treat the soil and wood, then fix the moisture that invited the termites in the first place. If you have seen mud tubes, sagging floors, or a musty smell in your McLean home, call (571) 773-0698 for a same-week inspection.
Live phone supportUpfront optionsBacked workmanship
What's included
What Our Crawl Space Termite Treatment Includes
Every termite treatment we sell includes the full inspection, the soil and wood treatment, and a written warranty. Moisture control and structural repair are priced separately so you can see exactly what each part of the job costs. Most McLean homeowners choose to bundle treatment with encapsulation because the termites come back without it.
Full Crawl Space Inspection
A licensed inspector crawls the entire space with a boroscope and moisture meter, checking every joist, sill plate, pier, and subfloor edge. You get photos, moisture readings, and a written report the same day.
Soil Termiticide Barrier
We apply a continuous termiticide barrier along the foundation wall and around every pier, creating a treated zone that foragers carry back to the colony. The barrier is rated for years of protection, not months.
Borate Framing Treatment
All accessible framing gets a borate treatment that penetrates the wood grain and stops termites from feeding. Borate also protects against future infestation and is safe for your family and pets once dry.
Mud Tube Removal and Sealing
We remove every active mud tube, seal the entry points, and document the locations so the follow-up inspection can verify the barrier is holding. This step is what turns a treatment into a permanent fix.
Moisture Readings and Report
We take six or more moisture readings across the crawl space and include them in your report. Those numbers tell you whether encapsulation and dehumidification are needed to keep termites from coming back.
Written Warranty and Follow-Up
Every treatment carries a written warranty, and we schedule a 12-month follow-up inspection at no charge. If termites return to a treated zone during the warranty period, we re-treat at no cost.
Service overview
What Crawl Space Termite Treatment McLean VA Actually Involves
Crawl Space Termite Treatment McLean VA is a licensed pest and moisture service that eliminates active termite colonies in the crawl space, treats the wood framing with a borate-based preservative, and corrects the damp conditions termites need to survive. We start with a boroscope inspection of every joist, sill plate, and pier, then map mud tubes, frass, and soft wood. Treatment combines a soil-applied termiticide barrier with a borate treatment on exposed framing. Because termites in Fairfax County almost always follow moisture, we pair every treatment with a vapor barrier or encapsulation liner and a Santa Fe or AprilAire dehumidifier to keep relative humidity under 55%.
Most McLean crawl spaces sit on clay-heavy soil that holds water after every storm, and the older homes in Chesterbrook, Franklin Park, and Salona Village were built before modern vapor barriers were standard. That combination is a termite buffet. We see active colonies in roughly one out of every four crawl spaces we inspect in 22101 and 22102. If you are searching for affordable crawl space termite treatment in McLean VA, the honest answer is that treating the termites without fixing the moisture means they come back within two seasons. We fix both.
How we workWe verify the cause, compare realistic options, and confirm the repair before we leave.
The service timeline
Our Crawl Space Termite Treatment Process
The process flexes to the condition, but these checkpoints keep decisions clear.
Full Inspection
A licensed inspector crawls the entire space with a boroscope and a moisture meter, checking every joist, sill plate, pier, and subfloor edge. We photograph mud tubes, frass, and soft wood, and we take moisture readings at six or more points. You get the photos and a written report the same day. Typical inspection runs 60 to 90 minutes.
Treatment Plan
We price the termite treatment separately from the moisture work so you can see exactly what each part costs. The plan lists the termiticide, the borate treatment on framing, any joist or beam repair, and the encapsulation or vapor barrier scope. You approve it before we start, and the price does not move unless you add work.
Termite Treatment
We apply a soil termiticide barrier along the foundation wall and around every pier, then treat all accessible framing with a borate solution. Active mud tubes are removed and the entry points sealed. Most treatments take two to four hours. The treated zone is safe for your family and pets once it dries, usually within a few hours.
Moisture and Repair Work
If the inspection found rot, we sister or replace damaged joists and beams with pressure-treated lumber, then install a 20-mil encapsulation liner or vapor barrier and a Santa Fe dehumidifier sized to the cubic footage. This step usually runs one to two days depending on square footage and how much repair is needed.
Verification and Warranty
We re-check moisture levels with a meter, confirm the dehumidifier is holding 45-50% relative humidity, and walk you through the space. You get a written warranty on the termite treatment and on the encapsulation work. We schedule a follow-up inspection at 12 months to confirm the barrier is holding.
Tools & methods
Tools and Methods We Use for Crawl Space Termite Treatment
Purpose-built equipment, used by trained technicians, so the job is done accurately the first time.
Boroscope
Lets us see inside joists, sill plates, and wall cavities without cutting the wood open. We use it to confirm termite damage and to check that repairs are solid before we close the job.
Moisture Meter
Reads wood and soil moisture content at multiple points across the crawl space. Termites need wood above 20% moisture, so these readings tell us whether treatment alone will hold or whether encapsulation is required.
Thermal Imaging Camera
Finds hidden moisture behind framing, under subfloor, and around plumbing penetrations. It shows us where water is collecting before it becomes visible mold or a new termite feeding site.
HEPA Vacuum and Air Scrubber
Removes mold spores, pest debris, and dust from the crawl space after treatment. The air scrubber runs during the job so spores do not migrate into your living space.
Fogger
Applies a fine antimicrobial mist to framing and subfloor in areas a sprayer cannot reach. We use it after HEPA vacuuming to treat the whole surface, not just what we can see.
Santa Fe and AprilAire Dehumidifiers
Hold the crawl space at 45-50% relative humidity year-round, which is the range where termites stop thriving and mold stops growing. We size the unit to your cubic footage, not a generic box.
Mold Test Kit and Air Quality Sampler
Takes air and surface samples after treatment and encapsulation so you have before-and-after numbers. The lab report confirms the space is clean before we close the job.
Use cases
When McLean Homeowners Call Us for Termite Treatment
These examples show how the service framework adapts rather than forcing every call through one repair.
Sagged Floor Fixed in Langley Forest
A bouncy kitchen floor in a 1985 home. The inspection found two joists with termite damage that had hollowed the center of the boards, plus a slow plumbing leak that had been feeding the colony for years. → We repaired the plumbing leak, sistered both joists with pressure-treated lumber, treated the surrounding framing with borate, and encapsulated the crawl space. The floor is solid again and moisture readings are holding at 11-13% across the repaired area.
Real Estate Inspection Cleared in Franklin Park
A home inspector flagged termite damage on the sill plate two weeks before closing. The buyer's lender wanted documented treatment and repair before funding. The seller had no prior pest history and no idea how long the colony had been active. → We inspected the same day, treated the soil and framing, replaced the damaged section of sill plate, and provided a written report with photos and moisture readings. The lender accepted the documentation and the closing happened on schedule.
Problems we solve
Crawl Space Termite Problems We Solve in McLean
Termites are a symptom. The real problem is almost always moisture, and until that is fixed the colony comes back. Here are the issues we see most often in McLean crawl spaces and how we handle each one.
Active mud tubes on foundation walls and piers
We remove the tubes, apply a soil termiticide barrier around the foundation and every pier, and treat all accessible framing with borate. The barrier stops foragers from re-establishing the run, and the borate stops feeding on contact. Most colonies collapse within two weeks.
Sagging or bouncy floors above the crawl space
We inspect every joist with a boroscope, sister or replace the damaged ones with pressure-treated lumber, and treat the surrounding framing with borate. Then we fix the moisture source so the new wood does not become the next meal.
Musty odors rising into the living space
We treat the termites, remove moldy insulation and debris, HEPA vacuum the framing, and apply a Concrobium or Fiberlock antimicrobial coating. Then we seal the space and install a dehumidifier to hold humidity at 45-50% so the smell does not come back.
Standing water or wet soil under the vapor barrier
We install interior drainage that channels water to a sump pit, add a sump pump with a battery backup, and seal the foundation. Once the soil drains, the vapor barrier performs and the framing dries out.
Pricing process
Crawl Space Termite Treatment Cost in McLean VA
$850 - $9,000 depending on scope
Crawl Space Square Footage
A 900-square-foot crawl space takes less termiticide and less labor than a 3,000-square-foot space. Most McLean homes fall between 1,200 and 2,200 square feet of crawl space, which is where our typical pricing sits.
Extent of Termite Damage
If termites have hollowed joists or sill plates, we add structural repair to the scope. Sistering a joist costs less than replacing it, and replacing a main beam costs more than either. The inspection tells us which one you need.
Moisture Control Scope
A vapor barrier alone costs less than full encapsulation with a dehumidifier. We recommend the scope based on your moisture readings, not a sales target. If a barrier will hold the space dry, that is what we quote.
Customer reviews
What McLean Homeowners Say
★★★★★
“We found mud tubes on the pier in our 1968 ranch and panicked. TerraVault came out two days later, treated the whole crawl space, and showed us the moisture readings that explained why the termites showed up. They installed a vapor barrier and a dehumidifier in the same visit. Six months on, the space is dry and the follow-up inspection was clean.”
★★★★★
“Our inspector found termite damage in two joists under the kitchen. TerraVault sistered both joists, treated the framing with borate, and encapsulated the crawl space. They gave us a fixed price before starting and it did not change. The floor no longer bounces and the musty smell is gone.”
★★★★★
“We had a musty odor for two years and three other companies told us to just ventilate more. TerraVault found active termites and mold on the subfloor. They treated the termites, removed the moldy insulation, and sealed the space. The air upstairs is noticeably cleaner and my allergies are better.”
Questions before we arrive
Frequently Asked Questions About Crawl Space Termite Treatment in McLean
How much does crawl space termite treatment cost in McLean VA?
Most McLean crawl space termite treatments run $850 to $2,400 in 2026, depending on square footage and how much framing needs borate treatment. Adding encapsulation and a dehumidifier typically pushes the total to $4,500 to $9,000. Repairing rotted joists or beams is priced per board. We give you a fixed written price after the inspection, so the number you approve is the number you pay.
What are signs of termites in a crawl space in McLean?
The four signs we find most often are mud tubes on the foundation wall or piers, frass (small pellet-like droppings) under joists, wood that sounds hollow when tapped, and a musty odor that does not go away after ventilation. Sagging or bouncy floors are a late-stage sign. If you see any of these, call (571) 773-0698 and we will inspect within 48 hours.
How long does crawl space termite treatment take in McLean VA?
The termite treatment itself takes two to four hours on a typical McLean crawl space. If we are also installing encapsulation and a dehumidifier, plan on one to two full days. Structural repair for rotted joists adds a day or more depending on how many boards need sistering or replacement. We tell you the schedule up front so you can plan around it.
Can I treat crawl space termites myself in McLean VA?
You can buy consumer termiticide at a hardware store, but you cannot legally apply the restricted-use products that actually kill a subterranean colony, and you cannot reach the soil under a pier without disturbing the foundation. DIY sprays also miss the moisture problem that caused the infestation. Most DIY attempts we inspect fail within one season. A licensed treatment plus moisture control is the cheaper path over five years.
Related services
Related Crawl Space Services
Crawl Space Mold Removal
Termites and mold share the same wet wood. After we treat the colony, we remove mold growth from joists and subfloor with HEPA vacuuming and a Fiberlock antimicrobial coating so the space is clean, not just pest-free.
Crawl Space Mold Remediation
When termite damage has opened the wood grain to moisture, mold follows fast. Our remediation crew removes affected material, treats the framing, and verifies clearance with air quality testing before we close the job.
Crawl Space Mold Inspection
A mold inspection pairs naturally with termite treatment. We use thermal imaging and a moisture meter to find the wet zones that feed both problems, then document everything with photos for your records.Ready when you are
Get Crawl Space Termite Treatment McLean VA Before Damage Spreads
Termites work year-round in Fairfax County, and every week you wait is another week of chewing. Call (571) 773-0698 for a same-week inspection with photos, moisture readings, and a fixed written price. We treat the colony and fix the moisture that brought it in.
Talk with the local team
Request Crawl Space Termite Treatment
Call us at (571) 773-0698 or send an email and we'll get back to you the same business day. We schedule inspections Monday through Friday, 8 a.m. to 6 p.m., and we can usually be in your crawl space within 24 hours. If you've got water, mold, or a smell you can't place, we'll find it.