Guide for crawl space encapsulation contractors · checked 12 November 2026
Crawl space encapsulation software for liners, readings, permits and warranties
An encapsulation job is sold on a moisture meter reading and kept on a humidity log. The liner overlaps 6 inches at every seam and runs 6 inches up the wall, the dehumidifier that removes 70 pints a day on the box removes 43.7 at 65°F, North Carolina wants a permit for every conversion whatever it costs, and a pest inspector in Georgia has to write up a crawl space that is neither vented nor conditioned. This guide covers how the work runs, the code paths, the numbers and what to look for in software.
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Short answer
Most crawl space encapsulation contractors run on home improvement sales CRMs such as MarketSharp or Leap, or on home service software such as QuoteIQ, Jobber or Housecall Pro, plus a moisture meter, a hygrometer and often the app that comes with a connected dehumidifier. The deciding features are the in-home inspection with readings and photos, good/better/best options by liner thickness and drying method, the code path (vented, IRC R408.3 unvented, or North Carolina R409 closed), permits and termite inspection gaps, and the warranty and service plan that follow the house. Fieldproxy is one option. Best for processes that don't fit a template, set up for you: it is built around your readings, your packages and your state's rules.
6 in
Liner seams overlap 6 inches, sealed or taped, and the liner runs at least 6 inches up the stem wall (IRC R408.3 as adopted in South Carolina)
source: S.C. Code Regs. 8-1221, IRC R408.3 Unvented crawl space (Cornell LII)
1 cfm / 50 sq ft
Exhaust or conditioned supply air rate for an unvented crawl space; dehumidification is sized to the manufacturer instead
Any cost
North Carolina requires a permit to convert a vented crawl space to a closed one regardless of the price of the work
43.7 pints
What a 70 pint (rated at 80°F) crawl space dehumidifier removes per day at 65°F and 60% RH
source: Santa Fe Compact70 dehumidifier submittal sheet (Therma-Stor), model 4044110
How a job runs
One crawl space encapsulation job, from first call to paid
The order the work really happens in, and what has to be written down at each step so nothing is argued about later.
- 1
Take the lead and find out what started it
Encapsulation leads rarely come from someone asking for encapsulation. They come from a home inspection or a wood destroying organism report in a sale, a musty smell, cupping floors, a termite renewal, or a pest company that writes the crawl up. In Georgia the Structural Pest Control rules make inspectors note insufficient under-floor ventilation as a conducive condition on the Official Georgia Wood Infestation Inspection Report. The office needs the trigger, any closing date, who pays, and whether a pest or radon report already exists.
- 2
Inspect and measure the crawl space
The inspector crawls the whole space: wood moisture readings on joists, sills and subfloor, air temperature and relative humidity inside and outside, standing water, grade and downspouts, insulation hanging or wet, pests, existing vapor barrier coverage, vents, ductwork, and any gas appliance in the crawl. Measure clear height under joists and girders, since IRC R317.1 requires decay protection for wood joists closer than 18 inches and girders closer than 12 inches to exposed ground. Photos of every problem become the sales presentation.
- 3
Choose the code path
Three paths cover most houses. A vented crawl needs 1 sq ft of vent per 150 sq ft of floor, or 1 per 1,500 with a Class I vapor retarder on the ground. An unvented crawl under IRC R408.3 needs a continuous sealed liner plus one drying method: continuous exhaust at 1 cfm per 50 sq ft, conditioned supply air at 1 cfm per 50 sq ft, a plenum in existing houses, or dehumidification sized to the manufacturer's specifications. North Carolina has its own closed crawl space chapter, R409, with five moisture control methods.
- 4
Price good, better and best
Most quotes offer tiers built from the same parts: liner thickness (6, 10, 12 or 20 mil), walls covered with liner, foam board or neither, vents and rim sealed, drainage matting or a sump, and the drying method. This Old House puts basic encapsulation at about $3 to $7 per sq ft and up to $10 with serious moisture, totals from $1,500 to $15,000, and a dehumidifier at $800 to $2,000 installed with its wiring. Mold remediation, joist sistering and pest treatment are add-on lines, often by other trades.
- 5
Pull the permit and line up the trades
In North Carolina a vented-to-closed conversion needs a permit regardless of cost, because every R409.5 drying method adds or changes mechanical or electrical equipment. The dehumidifier, exhaust fan and house air methods do not need an H-3 heating license; the supply air and conditioned space methods do. Elsewhere, the dehumidifier circuit, a sump pump outlet and any duct work can still need an electrician or HVAC contractor and an inspection.
- 6
Prepare the space
Remove debris and old wet insulation, fix grade and downspouts outside, treat or remediate mold, repair or sister damaged wood, and add drainage where water runs in. If a furnace or water heater in the crawl is atmospherically vented, sort combustion air before sealing: ICC's CodeNotes say crawl spaces ventilated by mechanical means are not an acceptable source of combustion air, so many contractors require sealed combustion equipment or a dedicated outdoor air opening.
- 7
Install the liner, walls and seals
Lay the ground liner with 6 inch overlaps sealed or taped, run it at least 6 inches up the stem wall and attach and seal it there. Wrap and seal piers. In North Carolina, a wall liner must stop 3 inches below the top of the masonry wall as a termite inspection gap, and liner on beam columns is attached at least 4 inches up. Foam on walls in South Carolina must leave a 6 inch termite inspection gap along the top of the foundation wall and sill plate. Seal vents, rim and penetrations.
- 8
Start up the drying method and record the baseline
Mount and level the dehumidifier, run the condensate to a drain or pump, set the humidistat, and record the starting crawl RH, temperature and wood moisture readings at the same marked points as the inspection. EPA's mold guidance keeps indoor humidity below 60%, ideally 30 to 50%, and the long-used rule for decay risk is wood moisture content above 20%, a rule Forest Products Laboratory researchers found nothing in the literature to contradict.
- 9
Hand over, invoice and keep the system on a service plan
The homeowner gets a report with before and after photos, readings, the liner and dehumidifier warranty, and the permit closeout. Many companies sell an annual inspection: re-read the same points, clean or change the dehumidifier filter, check the pump and liner for tears, and record the logged humidity. Liner warranties are often transferable when the house sells, so the system record must follow the address, not the buyer.
What to record
The fields every crawl space encapsulation job should capture
Inspection and readings
- Trigger: home inspection, WDO report, odor, floor problem, pest renewal, radon result; closing date and paying party
- Crawl footprint in sq ft, perimeter in linear ft, average height, number of piers, access opening size and location
- Wood moisture % at marked points (sill, rim, joists, subfloor), crawl RH and temperature, outdoor RH and temperature, time of day
- Joist and girder clearance to soil, standing water, grade and downspouts, existing vents (count and size), existing ground cover %
- Gas appliances in the crawl and their venting type (atmospheric, sealed combustion), ducts and their condition
What was installed
- Code path: vented, IRC R408.3 unvented (which drying option), North Carolina R409 (which R409.5 method)
- Ground liner make, mil and class, sq ft, seam overlap and tape, wall height or wall treatment, pier wrap, termite gap height
- Wall insulation type and R-value (foam board, spray foam) and its ignition barrier, rim joist treatment, vents sealed
- Dehumidifier make, model, serial, rated pints, humidistat setpoint, drain or pump, circuit; or exhaust fan cfm, or supply register cfm
- Drainage matting, sump pump model and discharge, mold or wood repair done and by whom
Proof, permit and warranty
- Permit number, inspection date and result (North Carolina always; elsewhere when mechanical or electrical work is added)
- Licensed trades on the job: H-3 heating license for NC supply air or conditioned space, electrician for the circuit
- Before and after photos per area, startup RH and wood moisture at the same points, 30 day follow-up readings
- Liner warranty and dehumidifier warranty registration, transferable yes or no, service plan visits due
Rules and standards
The rules that shape the work, with their sources
| Rule | What it means on the job |
|---|---|
| IRC R408.3 unvented crawl space: the liner | Exposed earth is covered with a continuous vapor retarder. Joints overlap 6 inches and are sealed or taped, and the edges extend at least 6 inches up the stem wall and are attached and sealed to the wall or insulation. South Carolina's adopted text names ASTM E1745 Class A; the model IRC and Larimer County's handout say Class I (0.1 perm or less). source: S.C. Code Regs. 8-1221, IRC R408.3 Unvented crawl space (Cornell LII) |
| IRC R408.3: one of four drying methods | Continuously operated mechanical exhaust at 1 cfm per 50 sq ft with an air pathway to the common area and insulated walls; conditioned air supply at 1 cfm per 50 sq ft with a return pathway; a plenum in existing structures under M1601.5; or dehumidification sized in accordance with the manufacturer's specifications. source: S.C. Code Regs. 8-1221, IRC R408.3 Unvented crawl space (Cornell LII) |
| Vented crawl spaces: 1/150 or 1/1,500 | Larimer County's 2024 IRC handout: vents of 1 sq ft per 150 sq ft of crawl space, reducible to 1 per 1,500 with a Class I vapor retarder sealed or taped on the ground, R-30 in the floor above, access of 18 by 24 inches through the floor or 16 by 24 inches through a wall, and duct insulation of R-8 for ducts 3 inches and larger. source: Larimer County, Colorado, Community Development: Crawlspace requirements (2024 IRC), updated 4/28/2026 |
| Georgia: pest control operators police crawl space ventilation | Since 1 April 2014, Georgia's Structural Pest Control rules require inspection of under-floor ventilation on Wood Infestation Inspection Reports (item 9, conducive conditions) and on fungi and wood boring beetle treatments. The 1/1,500 vent reduction needs 90% of the ground covered with a Class I retarder; an unvented crawl must meet R408.3; a dedicated dehumidifier supplying at least 2 cfm per 100 sq ft must drain automatically. source: Georgia Department of Agriculture, Structural Pest Division: Compliance Fact Sheet, Under-floor space ventilation |
| North Carolina: permit for every conversion (NCACP 106.1, 2025) | Converting a wall-vented crawl space to a closed crawl space under 2018 NCRC R409 needs a permit regardless of cost, because each R409.5 moisture method adds or changes heating, air conditioning or electrical equipment, which triggers N.C.G.S. 143-138(b5)(3) and 160D-1110(c)(3). Otherwise the residential no-permit threshold is $40,000. source: NC Department of Insurance, OSFM: Permit required for closed crawl space (2018 NCACP 106.1), 11 Dec 2025 |
| North Carolina: R409.5 methods and the H-3 license | Five moisture control methods: dehumidifier with condensate pump or drain and an outlet, supply air from the house AC, house air blown in by a fan, an exhaust fan, or a heated and cooled conditioned space. The State Board of Examiners of Plumbing, Heating and Fire Sprinkler Contractors says supply air and conditioned space need an H-3 license; dehumidifier, house air and exhaust fan do not. source: NC Department of Insurance, OSFM: Closed crawl space moisture control, permitting and H3 licensure (2018 NCRC R409.5), 20 Mar 2019 |
| North Carolina: wall liner termite gap (R409.2.2) | The ground vapor retarder may be run up the walls as a full liner but does not have to be. If it is, it stops 3 inches below the top of the masonry foundation wall as a termite inspection gap. It must be sealed to walls and beam columns, at least 4 inches up the columns. source: NC Department of Insurance, OSFM: Polyethylene ground vapor retarder permitted as wall liner (2018 NCRC R409.2.2), 16 Apr 2026 |
| Foam on crawl space walls: termite inspection gap (IRC R318.4) | As adopted in South Carolina: foam plastic in crawl spaces leaves a termite inspection gap of at least 6 inches along the top of the foundation wall and sill plate, foam above grade stays 6 inches from exposed earth, and in very heavy termite probability areas foam may not go on or under foundation walls below grade. source: S.C. Code Regs. 8-1216, IRC R318.4 Foam plastic protection (Cornell LII) |
| Decay protection near the soil (IRC R317.1) | Wood joists or the bottom of a wood floor closer than 18 inches, or wood girders closer than 12 inches, to exposed ground in a crawl space must be naturally durable or preservative treated. Low crawls are where the inspection finds untreated framing that needs a plan before it is sealed in. source: NC Department of Insurance, OSFM: Formal interpretation quoting 2018 NCRC R317.1 Location required (decay protection) |
| Combustion air once the crawl is sealed | Crawl spaces count as a combustion air source only when they have adequate natural ventilation directly to the outdoors; crawl spaces ventilated by mechanical means are not an acceptable source. Outdoor openings are sized at 1 sq in per 4,000 Btu/h for direct or vertical ducts. source: ICC Building Safety Journal, CodeNotes: Gas appliance combustion, ventilation and dilution air, Part 1 (outdoor air methods) |
| Insulate the walls of an unvented crawl, the floor of a vented one | Under 2021 IRC R1102.2.11 the walls of an unvented crawl space are insulated instead of the floor; the prescriptive table is commonly summarized as R-10 continuous or R-13 cavity in climate zones 4 to 8. Local amendments change this: Larimer County asks for R-15 continuous with no exposed paper or combustible facings. source: Jaspector, 2021 IRC: Do I insulate the crawl space walls or the floor above? (R1102.2.11 summary) |
| Ground retarder classes (ASTM E1745) | Plastic vapor retarders in contact with soil are specified as Class A, B or C. All three are 0.1 perm or less; they differ in tensile strength (45.0, 30.0 and 13.6 lbf/in) and puncture resistance, which is why mil thickness alone does not tell you the class. source: ASTM E1745-17 (reapproved 2023), Plastic water vapor retarders used in contact with soil (Class A, B, C), sample |
| The humidity and wood moisture targets | EPA's mold guidance: keep humidity below 60%, ideally 30 to 50%. Forest Products Laboratory researchers reviewing above-ground decay found nothing in the literature contradicting the 20% wood moisture content rule. source: US EPA, Tribal IAQ Resource Directory: Mold and moisture (humidity below 60%, ideally 30 to 50%) |
| Why closed crawls are sold in the Southeast | Advanced Energy's DOE-funded field study compared 12 matched houses on one cul-de-sac and concluded that a properly closed crawl space is a robust measure in humid southeastern conditions, producing a substantially drier crawl and significantly lower annual conditioning energy. Energy Vanguard's summary: the closed crawls stayed under 60% RH all summer while the vented ones tracked outdoor humidity. source: Davis et al., Advanced Energy, A field study comparison of ventilated versus sealed crawl spaces in the South (DOE/OSTI 850459, June 2005) |
Rules vary by state, council and contract. Checked 12 November 2026; confirm against the source for your area before relying on it.
Numbers
The numbers on an encapsulation quote and startup sheet
Code rates, manufacturer ratings and one published price guide. Dehumidifier capacity is rated at 80°F; crawl spaces usually run cooler, so read the low-temperature line.
| Item | Figure | Source |
|---|---|---|
| Liner seam overlap and wall run-up | 6 in overlap, 6 in up the stem wall | IRC R408.3 (SC 8-1221) |
| Exhaust or supply air, unvented crawl | 1 cfm per 50 sq ft | IRC R408.3; Larimer County |
| Georgia dedicated dehumidifier option | At least 2 cfm per 100 sq ft, auto drain | Georgia SPCC fact sheet |
| Vent area, vented crawl | 1 sq ft per 150 sq ft; 1 per 1,500 with Class I cover | IRC R408; Larimer County |
| Crawl access opening | 18 x 24 in (floor) or 16 x 24 in (wall) | Larimer County |
| NC wall liner top | 3 in below top of masonry wall | NC OSFM R409.2.2 |
| SC foam termite gap | 6 in at top of wall and sill | IRC R318.4 (SC 8-1216) |
| Wood clearance needing decay protection | Joists under 18 in, girders under 12 in | IRC R317.1 |
| 70 pint dehumidifier at 65°F, 60% RH | 43.7 pints/day | Santa Fe Compact70 sheet |
| Same unit, crawl coverage (5 ft height) | 1,800 to 2,600 sq ft | Santa Fe Compact70 sheet |
| Same unit, operating range | 49°F to 95°F | Santa Fe Compact70 sheet |
| Target humidity | Below 60%, ideally 30 to 50% | US EPA |
| Wood decay rule of thumb | 20% moisture content | USDA FPL (Carll and Highley) |
| Encapsulation price | $3 to $7 per sq ft, up to $10 | This Old House |
| Dehumidifier installed | $800 to $2,000 | This Old House |
source: S.C. Code Regs. 8-1221, IRC R408.3 Unvented crawl space (Cornell LII)source: Larimer County, Colorado, Community Development: Crawlspace requirements (2024 IRC), updated 4/28/2026source: Georgia Department of Agriculture, Structural Pest Division: Compliance Fact Sheet, Under-floor space ventilationsource: NC Department of Insurance, OSFM: Polyethylene ground vapor retarder permitted as wall liner (2018 NCRC R409.2.2), 16 Apr 2026source: S.C. Code Regs. 8-1216, IRC R318.4 Foam plastic protection (Cornell LII)source: NC Department of Insurance, OSFM: Formal interpretation quoting 2018 NCRC R317.1 Location required (decay protection)source: Santa Fe Compact70 dehumidifier submittal sheet (Therma-Stor), model 4044110source: US EPA, Tribal IAQ Resource Directory: Mold and moisture (humidity below 60%, ideally 30 to 50%)source: Carll and Highley, USDA Forest Products Laboratory (1999), Decay of wood and wood-based products above ground in buildingssource: This Old House, Crawl space encapsulation cost
Where it breaks
Where spreadsheets and generic software fall over
A salesperson quotes a 70 pint dehumidifier for a 2,400 sq ft crawl from the box rating. The crawl sits at 62°F in spring, the unit removes far less than 70 pints, and the humidity log never drops below 65%.
The quote sizes the dehumidifier from the crawl's measured temperature, height and sealing level against the model's low-temperature rating and coverage table, and flags any unit sized only from the 80°F number.
A North Carolina crew closes a crawl with a dehumidifier and skips the permit because the job was $9,000. The inspector finds it at resale.
Jobs with a North Carolina address carry a required permit step whatever the price, and the R409.5 method picked on the quote decides whether an H-3 license holder must be on the job.
The liner goes up to the sill plate. The termite company later refuses to renew the bond because there is no inspection gap.
Wall treatment fields carry the state's gap rule (3 inches below the top of masonry in North Carolina, 6 inches for foam in South Carolina) and the install checklist asks for a photo with a tape at the gap.
An atmospheric gas water heater sits in the crawl. The crew seals every vent, and the appliance now has no combustion air.
Gas appliances and their venting type are inspection fields; an atmospheric appliance blocks the 'seal vents' line until a combustion air plan or a sealed combustion replacement is on the quote.
The inspection readings live on a sales rep's tablet. A year later the homeowner says the floors still cup and nobody can show the startup numbers.
Readings are stored per marked point on the property, so the startup and each annual visit read the same sill, rim and joist points and the trend is on one page.
The house sells and the new owner calls about a torn liner. The office cannot find the job because it was filed under the seller's name.
The system and its transferable warranty sit on the property record; the sale updates the owner and the service plan continues.
Checklist
The crawl space encapsulation operations checklist
Print it, or hand it to whoever runs the office side.
- Lead trigger, closing date, paying party and any WDO, home inspection or radon report attached
- Footprint, perimeter, height, piers and access opening measured
- Wood moisture and RH readings at marked points, inside and outside, with time
- Joist and girder clearance checked against 18 and 12 inches
- Gas appliances in the crawl and their venting recorded before any sealing
- Code path chosen: vented, R408.3 unvented with drying method, or NC R409 with R409.5 method
- Dehumidifier sized from crawl temperature, height and sealing, not only the 80°F rating
- Permit pulled where required (every NC conversion) and licensed trades booked
- Grade, downspouts, standing water, mold and damaged wood dealt with first
- Liner seams overlapped 6 inches and sealed, 6 inches up the wall, piers wrapped
- Termite inspection gap left at the state's height and photographed
- Startup RH, temperature and wood moisture recorded at the same points
- Warranty registered and transferable terms on the property record
- Annual service visit booked with filter, pump, liner and readings
Software options
What software crawl space encapsulation contractors actually use
Judge each one on whether it fits the way your jobs run, not on the feature list. Bring a real job to every demo.
MarketSharp
In-home sales companies selling encapsulation, waterproofing and insulation
Home improvement CRM for lead tracking and follow-up. Crawl Space Ninja used it to mark appointment results such as demo sale or demo maybe and trigger different follow-ups. Field readings and permits sit elsewhere.
Leap (SalesPro)
Contractors who sell at the kitchen table on a tablet
CRM plus an in-home sales app for presenting options, pricing and signing. Built for home improvement sales in general rather than crawl space readings.
QuoteIQ
Small and mid-size crawl space companies wanting quotes, scheduling and invoices in one app
Plans from $29.99 to $399.99 a month; markets tiered encapsulation options, satellite footprint measuring and crawl space inventory. It publishes its own ranking that puts itself first.
Jobber or Housecall Pro
Owner-operated crews doing encapsulation alongside other home services
Strong on quotes, scheduling, invoices and reviews. Readings by marked point, permit and termite gap rules, and transferable warranties would be custom fields and reminders.
Basement Systems dealer network tools
One of the 350+ contractors in the Basement Systems network selling CleanSpace
Basement Systems says its products, such as the 20 mil, 7-ply CleanSpace liner, are sold only through local contractors in its network. The product line is fixed; the dealer still needs its own system for readings, permits and service plans.
Published prices, compared:source: Pro Remodeler, How better sales tracking accelerated growth for Crawl Space Ninja (MarketSharp)source: FDD Ninja, Crawl Space Ninja 2024 FDD Item 20: franchised outlets at end of 2023source: Leap, Sales software for the modern contractor (CRM and SalesPro in-home app)source: QuoteIQ, CRM for crawl space companies (plans and features)source: Basement Systems, CleanSpace crawl space vapor barrier (20 mil, 7-ply, dealer network)
Questions to ask any vendor
- Can the field app hold wood moisture and RH readings at named points under the house, offline, and show them against the next visit's readings?
- Can a quote carry good, better and best options built from liner mil, wall treatment and drying method, with the dehumidifier sized from crawl temperature?
- Can it require a permit step on every North Carolina conversion and an H-3 license holder when the method is supply air or conditioned space?
- Can install checklists demand a photo of the termite inspection gap at the right height for the state?
- Does the system and its warranty live on the property, so a resale moves it to the new owner with the service plan intact?
- Can it track dehumidifier serials, filters and warranty registrations as inventory and service history?
Bring one real crawl space encapsulation job. We show it running in Fieldproxy.
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Crawl space encapsulation on Fieldproxy: built around how you already work
A Fieldproxy setup for a crawl space encapsulation company is built around the crawl as a measured space: footprint, readings at marked points, the code path, the drying method and the warranty that stays with the house. State rules (North Carolina permits and H-3 licensing, termite inspection gaps, Georgia's pest board ventilation checks) are built into statuses and blocks, so a job cannot be sealed up ahead of its paperwork.
Module 1
Lead intake and trigger
Most jobs start from someone else's report, often with a closing date.
- Records: Customer (owner, buyer, seller, landlord, builder, pest company partner) > Property > Crawl space > Job
- Fields: trigger (home inspection, WDO report, odor, floor cupping, pest renewal, radon result), report PDF, closing date, paying party, referring pest company
- Status: New, Inspection booked, Inspected, Quoted, Sold, Permit pending, Prep, Installed, Startup logged, Closed, Service plan
Module 2
Crawl space inspection form
The readings and photos are the sale, and later the proof.
- Dimensions: footprint sq ft, perimeter ft, average and minimum height, piers, access opening size; crawl volume calculated
- Marked reading points (e.g. NE sill, center joist, rim at kitchen) with wood moisture %, plus crawl and outdoor RH and temperature with time
- Checklist: standing water, grade, downspouts, existing cover %, vents count and size, insulation condition, pests, joists under 18 in and girders under 12 in from soil
- Gas appliances in the crawl with venting type; atmospheric venting raises a combustion air flag
Module 3
Good, better, best quote builder
Every company sells tiers; the parts and the sizing must be right in each.
- Lines priced from measurements: liner sq ft by mil (6, 10, 12, 20), wall liner or foam board by perimeter and height, pier wraps by count, vent and rim sealing, drainage matting, sump
- Drying method per tier: dehumidifier model chosen against crawl temperature, height and sealing level from the manufacturer's coverage table; exhaust fan cfm or supply register cfm at 1 per 50 sq ft
- Add-on lines for mold remediation, wood repair, pest treatment and electrical, with the trade that does each
- Customer-signed option on a quote PDF from your template, with photos from the inspection
Module 4
Code path and permit rules
The path decides the drying method, the permit and who must be licensed.
- Code path picker: vented, IRC R408.3 unvented (which of the four options), North Carolina R409 (which R409.5 method)
- Block: a North Carolina conversion cannot move to Installed without a permit number; supply air or conditioned space methods need an H-3 license holder on the job
- Permit record: number, jurisdiction, inspection date, result, closeout photo
- Combustion air flag must be cleared (sealed combustion unit or outdoor air plan) before the vent sealing line is scheduled
Module 5
Crew scheduling across prep and install
Prep, mold, wood repair, electrical and liner work are different crews and sometimes different companies.
- Job phases: clean-out, drainage, remediation, wood repair, liner, walls, dehumidifier and circuit, startup
- Subcontractor phases for electricians and HVAC with their license numbers and insurance expiry
- Material pick list per job from the quote: liner rolls by mil, seam tape, fasteners, foam board, dehumidifier, pump
Module 6
Install checklist in the field app
The details inspectors and termite companies check are easy to skip under a house.
- Required: seam overlap confirmed 6 in and taped, liner height on wall, pier wraps, vents sealed, rim treatment
- Termite gap: required height by state (3 in below masonry top in NC for wall liner, 6 in for foam in SC) and a photo with a tape
- Wall insulation type, thickness and R-value, ignition barrier where the foam needs one
- Works offline under the house; photos tagged to the marked reading points
Module 7
Startup and readings log
A closed crawl is judged by its numbers over time.
- Startup: dehumidifier serial, setpoint, drain or pump, circuit; RH, temperature and wood moisture at the same marked points
- Follow-up reading at e.g. 30 days and each annual visit; chart per point against the 60% RH and 20% wood moisture lines
- A reading above target opens a callback with the inspection, quote and startup data attached
Module 8
Equipment, warranty and service plan
Dehumidifiers, pumps and liners have serials, filters and warranties that outlive the sale.
- Asset per property: dehumidifier and pump model and serial, install date, warranty end, filter change interval, liner make and warranty terms, transferable yes or no
- Annual service plan: inspect liner, clean or change filter, test pump, read the points; renewal invoiced automatically
- Resale updates the owner on the property and keeps the warranty and plan
Module 9
Homeowner and partner portal
Buyers, sellers, agents and pest partners all want the same proof.
- Per property: before and after photos, readings chart, permit closeout, warranty certificate, invoice
- Pest company partners see the termite gap photos and the referral status of their leads
- QuickBooks or Xero sync for invoices and financing payments
The AI agents, set up for crawl space encapsulation contractors
| Agent | When | What it does | What you get |
|---|---|---|---|
| Document intelligence agent | A home inspection report, WDO report or pest company referral PDF arrives by email | Reads the address, the crawl space findings (moisture, vapor barrier, ventilation, wood damage), the closing date and the referring company | A new lead with the trigger, report and closing date filled and an inspection request queued |
| Vision agent | The inspector or installer photographs a moisture meter, a hygrometer, a dehumidifier nameplate or the termite gap with a tape | Reads the reading, the model and serial, and the measured gap | Reading points, the equipment asset and the gap field filled on the checklist |
| Watcher agent | A North Carolina job moves toward Installed with no permit, a vent sealing line is scheduled with an atmospheric appliance unresolved, or a follow-up reading comes in above e.g. 60% RH | Checks the job against the code path, permit and readings on file | A blocked status change with the reason, or a callback job, and an alert to the production manager |
| Autopilot | A quote sits unsigned e.g. 3 days before a closing date, or an annual service visit is e.g. 30 days away | Drafts the follow-up with the inspection photos and options, or the service visit booking for the current owner | A draft a person approves before it sends |
| Scheduler agent | Every Monday at 7 am | Lists inspections this week, quotes open by tier, permits pending, jobs waiting on remediation or electrical, crawls above target humidity and service visits due | A weekly briefing emailed to the owner and production manager |
Straight answers
Crawl space encapsulation: FAQ
What software do crawl space encapsulation contractors use?
Many use home improvement sales CRMs such as MarketSharp or Leap, or home service software such as QuoteIQ, Jobber or Housecall Pro, plus moisture meters, hygrometers and the apps that come with connected dehumidifiers. What matters is storing readings at fixed points, quoting tiers with the right dehumidifier, permit and termite gap rules by state, and warranties that follow the house. Fieldproxy is set up around your own readings, packages and states.
What does the IRC require for an encapsulated (unvented) crawl space?
Under IRC R408.3: a continuous vapor retarder over exposed earth with 6 inch overlaps sealed or taped, run at least 6 inches up the stem wall and sealed there, plus one drying method: continuous exhaust at 1 cfm per 50 sq ft, conditioned supply air at 1 cfm per 50 sq ft, a plenum in existing houses, or dehumidification sized to the manufacturer's specifications.
Do you need a permit to encapsulate a crawl space?
It depends on the state and what is added. North Carolina's Office of State Fire Marshal says converting a vented crawl to a closed crawl under R409 needs a permit regardless of cost, because every drying method adds or changes mechanical or electrical equipment. Elsewhere, a new dehumidifier circuit or duct work can still need a permit.
Who can install the drying system in a North Carolina closed crawl space?
The State Board of Examiners of Plumbing, Heating and Fire Sprinkler Contractors says the supply air and conditioned space methods need an H-3 heating license; the dehumidifier, house air and exhaust fan methods do not. Electrical work can need its own license.
What size dehumidifier does a crawl space need?
Size from the manufacturer's crawl space table, not the headline pints. Santa Fe's Compact70 is rated 70 pints a day at 80°F and 60% RH but 43.7 pints at 65°F, and covers 1,800 to 2,600 sq ft of crawl at a 5 foot height depending on how tightly the space is sealed. Georgia's pest rules describe a dedicated dehumidifier option of at least 2 cfm per 100 sq ft with an automatic drain.
What humidity should an encapsulated crawl space hold?
EPA's mold guidance says keep humidity below 60%, ideally 30 to 50%. In Advanced Energy's North Carolina study the closed crawl spaces stayed under 60% RH all summer, while the vented ones tracked outdoor humidity.
How thick should a crawl space vapor barrier be?
Code asks for a Class I vapor retarder (0.1 perm or less); 6 mil polyethylene meets that. Contractors sell 10, 12 and 20 mil liners for puncture and tear resistance where people crawl or store things. ASTM E1745 classes A, B and C differ in tensile strength and puncture resistance, not permeance.
Does encapsulation affect termite inspections?
It can. South Carolina's adopted IRC R318.4 requires foam in crawl spaces to leave a 6 inch termite inspection gap along the top of the foundation wall and sill plate. North Carolina requires a wall liner to stop 3 inches below the top of the masonry wall. Leaving no gap can make a termite company refuse to renew.
How much does crawl space encapsulation cost?
This Old House puts it at $1,500 to $15,000, about $5,500 on average, or $3 to $7 per sq ft for basic work and up to $10 with serious moisture. A dehumidifier adds $800 to $2,000 installed and mold remediation $500 to $4,000.
Can a furnace or water heater stay in an encapsulated crawl space?
Only with a combustion air plan. ICC's CodeNotes say crawl spaces ventilated by mechanical means are not an acceptable source of combustion air, so an atmospherically vented appliance needs outdoor combustion air openings sized to its input or replacement with sealed combustion equipment.
Related guides
All sources on this page (33)
- source: S.C. Code Regs. 8-1221, IRC R408.3 Unvented crawl space (Cornell LII)
- source: Larimer County, Colorado, Community Development: Crawlspace requirements (2024 IRC), updated 4/28/2026
- source: NC Department of Insurance, OSFM: Permit required for closed crawl space (2018 NCACP 106.1), 11 Dec 2025
- source: Santa Fe Compact70 dehumidifier submittal sheet (Therma-Stor), model 4044110
- source: Georgia Department of Agriculture, Structural Pest Division: Compliance Fact Sheet, Under-floor space ventilation
- source: NC Department of Insurance, OSFM: Closed crawl space moisture control, permitting and H3 licensure (2018 NCRC R409.5), 20 Mar 2019
- source: NC Department of Insurance, OSFM: Polyethylene ground vapor retarder permitted as wall liner (2018 NCRC R409.2.2), 16 Apr 2026
- source: S.C. Code Regs. 8-1216, IRC R318.4 Foam plastic protection (Cornell LII)
- source: NC Department of Insurance, OSFM: Formal interpretation quoting 2018 NCRC R317.1 Location required (decay protection)
- source: ICC Building Safety Journal, CodeNotes: Gas appliance combustion, ventilation and dilution air, Part 1 (outdoor air methods)
- source: Jaspector, 2021 IRC: Do I insulate the crawl space walls or the floor above? (R1102.2.11 summary)
- source: ASTM E1745-17 (reapproved 2023), Plastic water vapor retarders used in contact with soil (Class A, B, C), sample
- source: US EPA, Tribal IAQ Resource Directory: Mold and moisture (humidity below 60%, ideally 30 to 50%)
- source: Davis et al., Advanced Energy, A field study comparison of ventilated versus sealed crawl spaces in the South (DOE/OSTI 850459, June 2005)
- source: Carll and Highley, USDA Forest Products Laboratory (1999), Decay of wood and wood-based products above ground in buildings
- source: This Old House, Crawl space encapsulation cost
- source: Pro Remodeler, How better sales tracking accelerated growth for Crawl Space Ninja (MarketSharp)
- source: FDD Ninja, Crawl Space Ninja 2024 FDD Item 20: franchised outlets at end of 2023
- source: Leap, Sales software for the modern contractor (CRM and SalesPro in-home app)
- source: QuoteIQ, CRM for crawl space companies (plans and features)
- source: Basement Systems, CleanSpace crawl space vapor barrier (20 mil, 7-ply, dealer network)
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