Product
SlabCollar™
SlabCollar is a precision-molded EPDM boot that seals a 4″ Sch 40 pipe penetration through a concrete slab or thin-panel lid against radon, soil gas, and moisture vapor. It delivers four independent seal lines — three against the concrete, one on the pipe — from a single compression-fit part, with no sealant, no adhesive, and no fasteners.
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Four Seals, One Part
A soft top lip, two annular ribs, and an inner pipe flange form four independent compression seals — three against the concrete, one on the pipe — with no sealant, no adhesive, and no cure time.
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Two Install Modes
Seats in a ≈127 mm (5.0″) cored hole, or clamps a thin plastic or wood lid from 1/8″ to 1/2″ thick. One SKU covers both methods.
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Inspectable & Removable
Compression fit means the seal is visible, testable, and the pipe can be pulled and re-seated for service — no destructive tear-out.
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Engineered EPDM
50A-durometer EPDM rated −55 °C to +125 °C, with tested ozone resistance — the classic long-term failure mode for rubber seals below grade.
The Four Seals
Annotated Cutaway Diagram
Four independent seals — three on concrete, one on pipe.
Top sealing lipSeal
A soft, flexible lip presses flat to the slab face or lid top for a continuous surface seal.
Wide overhang
Reaches past the chipped edge of the cored hole onto solid concrete; locates and covers a lid opening.
Clamp-and-seal shoulder
In lid mode, seals the underside and clamps the panel top-and-bottom. Idle in concrete-core mode.
Inner pipe sealSeal
An inward flange (109 mm) grips the 4″ pipe OD, sealing the pipe-to-boot interface.
Dual annular compression sealsSeal
Two ribs at two heights compress against the cored-hole wall — two independent seal lines from one feature.
Support ledge
An internal shelf catches the cut pipe end so it can't drop into the hole, and supports over 200 lb.
Two Install Modes
| Feature | Concrete Core | Thin Lid (Plastic/Wood) |
|---|---|---|
| 1 Top sealing lip | Seals the slab surface | Seals the lid’s top face |
| 2 Wide overhang | Bridges to solid concrete; covers rough edge | Covers / locates on the lid |
| 3 Clamp-and-seal shoulder | Idle | Seals the underside and clamps the lid |
| 4 Inner pipe seal | Seals the pipe | Seals the pipe |
| 5 Dual compression ribs | Seal the hole | Idle (hang free below panel) |
| 6 Support ledge | Supports the pipe | Supports the pipe |
Why EPDM
Ozone & Water Resistance
Tested to ASTM D1171 with no ozone cracking, and low water uptake (+3.6% volume) — the two classic long-term failure modes for a seal at or below grade.
Temperature Range
Rated −55 °C to +125 °C — passed low-temperature brittleness at −55 °C (ASTM D2137) and heat ageing at 125 °C. Stays flexible in cold sub-slab conditions.
Compression Set
Tested compression set of 13% (ASTM D395, 100 °C) — the low-durometer EPDM holds its sealing force instead of taking a permanent set.
Fit & Compatibility
Compatible With
- •4″ Sch 40 PVC (OD 4.500″ / 114.3 mm)
- •4″ Sch 40 ABS (OD 4.500″ / 114.3 mm)
- •3″ Sch 40 via a 4×3 reducer (available today)
- •Core hole: ≈127 mm (5.0″)
- •Panel / lid thickness: 1/8″–1/2″ (3–13 mm)
Future Sizes
- •3″ Sch 40 — dedicated mold in development
- •2″ — in development, for block-wall sub-slab penetrations
Contact us for updates on additional sizes.