Concrete Sealing and Industrial Floor Sealers

What Concrete Sealing Actually Means on an Industrial Slab

The phrase covers three different things, and specifying the wrong one is the usual reason a sealed floor disappoints. A sealer is a thin film — most MavSeal products go down at 2–5 mils, and MavSeal UPA and MavSeal RCU at up to 16 mils — whose job is wear, stain, chemical and UV protection at the surface. A coating is a thicker body layer, such as the 100% solids epoxies on the epoxy flooring page, that builds film, hides slab variation and carries a pigment or broadcast. A moisture vapor barrier such as MavCoat MVB is neither: it is a primer applied directly to concrete to hold vapor drive below the floor, and its sheet says it must be over-coated with a more durable Maverick system.

Two honest limits follow from that. First, the MavSeal topcoats are formulated to go over a primed or coated floor, not raw concrete; the sheets for MavSeal HTU, UHD, HSU and RCU each say so, and MavSeal UPA is designed for floors broadcast to refusal rather than smooth coatings. The clear film that does go straight onto bare or green concrete is MavPrime MVT, a 100% solids, zero-VOC epoxy that its sheet lists as a stand-alone coating or sealer. Second, Maverick does not sell a silicate densifier. Where a bare slab needs hardening rather than a film, we test it and specify the fix case by case, usually inside a concrete floor repair or moisture mitigation scope.

Three layers, three jobs

• Sealer. Thin wear film at 2–16 mils: MavSeal UPA, HWU, HTU, UHD, HSU, RCU and MavCoat CES. It decides gloss, UV stability, abrasion loss and chemical resistance at the surface.
• Coating. Body layer at 10–30 mils that builds thickness and carries pigment or a broadcast; see warehouse floor coatings for how the two are stacked.
• Barrier primer. MavCoat MVB at 16 mils resists moisture vapor transmission up to 25 lbs. per 1,000 sq. ft. in 24 hours (ASTM F1869) or 95% RH (ASTM F2170), then gets over-coated.
• Sealer-primer. MavPrime MVT at 8–10 mils per coat on green concrete: one coat up to 85% slab RH, two full coats above it.

Choosing a Floor Sealer by What the Floor Sees

We do not pick a sealer by finish and hope it holds up. We ask what reaches the surface — daylight, hard wheels, chemistry, or a schedule that cannot wait — and let the data sheet answer. Most industrial floors see two or three of these at once. A warehouse with a south-facing dock door, a battery-charging corner and a 48-hour shutdown window is a normal brief, not a hard one, and it usually resolves to a urethane on the aisles and a polyaspartic or polyurea on the sections that have to open first.

Three cases fall outside a thin sealer. Where the exposure is primarily chemical, the chemical-resistant linings page covers novolac and containment builds; a 3-mil film is a wear layer, not a lining. Where the floor is a parking or traffic deck, the sealer is the final coat in a parking deck and traffic coating system rather than a stand-alone product. And where the real problem is water coming up through the slab, no sealer fixes it; that belongs to moisture mitigation and MavCoat MVB, and sealing over it only moves the failure to the bond line.

Match the sealer to the exposure

• UV and daylight. Aliphatic chemistry only. MavSeal UPA holds 87–89 gloss after 1,000 hours QUV (ASTM G154) and is rated for exterior use; MavCoat CES holds above 85. MavSeal HSU, HTU and UHD are non-yellowing but their sheets limit them to interior service.
• Forklift and hard-wheel wear. MavSeal HWU at 12 mg Taber loss, then HTU and UHD at 20 mg with the high-wear filler. These are the sealers for warehouse and distribution aisles.
• Chemical splash. MavSeal HWU is rated Excellent on its sheet for 10% and 30% hydrochloric acid, 50% sodium hydroxide, MEK and xylene; MavSeal UPA is Excellent for motor oil, brake fluid, E85, bleach and MEK. Confirm the specific reagent against the sheet before specifying.
• Fast turnaround. MavSeal RCU returns to foot traffic in 3 hours and full service in 24. MavSeal UPA Fast takes foot traffic in 4–6 hours and heavy traffic in 48, and is the version required below 60°F, down to 35°F air and surface. See the polyaspartic system and polyaspartic floor coating pages.
• Occupied, low-odor spaces. MavSeal HSU, HTU and UHD at 16 g/L VOC, MavPrime MVT at zero VOC, and MavCoat CES, which is isocyanate free.

Surface Preparation and Moisture Limits Before Any Sealer Goes Down

A thin film has no margin for a bad substrate. Every sheet in the line starts the same way: concrete sound, clean and dry; new concrete cured a minimum of 28 days; and, for the urethane and polyurea topcoats and MavPrime MVT, a minimum surface tensile strength of 300 psi per ASTM D4541. Profile is mechanical, never acid etch. MavSeal HWU and MavCoat CES, which go over an epoxy primer and basecoat, call for CSP 1–3 on the concrete (SSPC-SP13/NACE 6 or ICRI 310.2); MavSeal HTU, UHD, HSU, RCU and MavPrime MVT call for CSP 3–5 per ICRI 310.2R, equal to 60-grit sandpaper or coarser. Our CSP guide explains the choice.

Moisture is tested on every slab, not assumed. The sealer sheets set the same ceiling: moisture vapor transmission no more than 3 lbs. per 1,000 sq. ft. in 24 hours per ASTM F1869 and in-situ relative humidity below 75% per ASTM F2170, with a heavy, unruptured vapor barrier under any slab on grade. MavCoat WBE, which is vapor permeable, allows 10 lbs. and 80% RH. Green concrete gets MavPrime MVT: one 8–10 mil coat up to 85% slab RH, two full coats above it. Where the slab fails outright, the build starts with MavCoat MVB — 16 mils, resistant to 25 lbs. or 95% RH — and the sealer becomes the top of a system. The slab stays at least 5°F above the dew point, and primer goes down while the slab is cooling to limit outgassing.

Prep numbers from the sheets

• 28 days. Minimum cure for new concrete before a MavSeal or MavCoat sealer; earlier than that is MavPrime MVT territory.
• 300 psi. Minimum surface tensile strength, ASTM D4541, on the urethane, polyurea and MavPrime MVT sheets.
• CSP 1–3 or 3–5. Diamond grinding or shot blasting to the profile the sheet names; the CSP 3–5 products equate it to 60-grit sandpaper or coarser.
• 3 lbs. / 75% RH. MVT and slab RH ceilings (ASTM F1869 / F2170) for the sealers; 10 lbs. / 80% for MavCoat WBE; 25 lbs. / 95% once MavCoat MVB is under the system.
• Repairs first. Cracks, joints and spalls are addressed before the sealer goes down; see concrete floor repair.

Keeping a Sealed Floor Sealed

The sheets are blunt about it: dirt and debris tracked over a finished floor will quickly scratch and dull the surface, so a sealed floor needs a routine maintenance program from day one. Walk-off mats at entrances. Sweep, then mop or auto-scrub with soft bristles or pads and a mild cleaner; some cleaning products and equipment, or improper use of them, can damage the surface. Remove spills quickly and keep sloped floors draining so water and chemicals do not stand. Where vehicles or heavy items on rubber wheels sit for long periods, the MavSeal HWU and MavCoat CES sheets recommend a piece of nonporous material such as sheet metal or plexiglass between tire and floor, because tire marking may occur.

Reapplication may be necessary in heavy-traffic areas, and the recoat rules decide how easy that is. Inside the recoat window a sealer bonds to the layer below; MavSeal RCU and MavPrime MVT set that window at 24 hours (RCU at 70°F), and MavSeal HSU and UHD go over a MavCoat epoxy within 24 hours of its installation. Outside the window the floor is abraded, not just cleaned: 60-grit sanding or diamonds for MavSeal HWU; 80/100 grit until no gloss is visible, then vacuum and tack, for MavCoat CES; 100-grit or finer pads and a 50:50 water and isopropanol wipe for MavSeal HSU. A planned recoat of a 2–5 mil sealer is a weekend's work, which is the point of a sacrificial wear layer on an industrial floor.

Return to service, from the sheets

• MavSeal RCU. Foot traffic 3 hours, full service 24 hours at 77°F.
• MavSeal UPA Fast. Foot traffic 4–6 hours, heavy traffic 48 hours; the Slow and XTRA Slow versions trade return time for working time in heat and humidity.
• MavSeal HSU, HTU, UHD. Foot traffic 12 hours, full service 48 hours; no parked vehicles for 36 hours.
• MavSeal HWU. Light foot traffic 20 hours, heavy traffic 48 hours, full cure 5 days.
• MavCoat CES. Light foot traffic 12–16 hours, full cure 5 days.
• MavCoat WBE. Foot traffic 24 hours, full service 48–72 hours.

Floor Sealing Contractor for Michigan, Ohio and the Midwest

Maverick is based at 25911 Northline Commerce Drive, Suite 306, Taylor, MI 48180, and our crews seal and coat floors across Metro Detroit, Southeast Michigan, the rest of Michigan, Ohio and the Midwest. Because we formulate the MavSeal and MavCoat products in our own plants and install them with our own people, one company owns the moisture test, the profile, the mix and the finished surface. Every project carries a single-source warranty covering materials and labor, with the term set per project.

The sealers on this page show up most often on warehousing and distribution floors, in manufacturing plants, in transportation and fleet facilities, and as the traffic-bearing top of parking deck systems. If you can tell us the square footage, the age of the slab, what runs on it and the shutdown window you have, we can usually name the sealer before we arrive; the moisture test and a bond test on site confirm it. Specifiers can pull every sheet cited here from the product data sheet library.

What a quote needs

• Slab facts. Age, on grade or suspended, known vapor barrier, prior coatings or curing compounds.
• Exposure. Wheel type, chemicals handled, daylight at doors, wash-down practice.
• Window. Hours available per section and whether the operation runs around the work, as it does on our warehouse jobs.
• Finish. Clear or pigmented with MavTints; gloss, satin or low sheen.