APF VaporSolve LP | 99% RH Moisture Mitigation Epoxy
APF VaporSolve LP (Low Perm) is a specialized, 100% solids epoxy coating engineered to isolate moisture-sensitive flooring systems from concrete with high moisture levels. It acts as a high-performance moisture mitigation layer, designed to prevent the devastating flooring failures caused by excessive moisture vapor transmission through the slab.
VaporSolve LP is suitable for concrete substrates showing up to 99% Relative Humidity (RH) when measured in accordance with ASTM F2170. It is part of the proven APF VaporSolve system, formulated for low viscosity and superior substrate wetting to promote deep penetration and a permanent bond, even to damp concrete.
Technical Performance Snapshot
| Physical Property |
Value |
| Maximum Moisture Rating |
99% RH (ASTM F2170) |
| Permeability (ASTM E-96) |
0.01 Perms |
| Adhesion to Concrete (ASTM D-4541) |
>500 psi (Concrete Failure) |
| Pot Life / Bucket Time (ASTM D2471) |
10–15 Minutes at 77°F |
| VOC Content |
<50 g/L |
Critical Bucket Time Warning: VaporSolve LP has an extremely short pot life of 10–15 minutes. You must pour the material out of the pail immediately after mixing. If left in the bucket, the material will rapidly generate heat and kick, significantly reducing your application window. Once spread on the cooler concrete surface, your actual working time will extend, but the material must get out of the pail immediately.
The Silicate Conflict
If the concrete surface is known or suspected to have been treated with silicates, densifiers, or reactive silicate curing compounds, the use of APF VaporSolve Primer is required before applying VaporSolve LP. Shot-blasting or diamond grinding alone will not reliably remove metasilicate residues from within the concrete pores. In these cases, the primer is a mandatory step to bridge the gap and ensure the system maintains a permanent bond.
Where This Product Fits in a System
APF VaporSolve LP is used below moisture-sensitive flooring systems (Epoxy, Urethane, Polyaspartic, or Cementitious Overlays) when elevated concrete moisture is present. It is a functional moisture control membrane designed to isolate the finished floor from moisture vapor coming through the slab.
Packaging and Coverage
Packaging: Supplied in complete A+B units in 1.5 gallon and 3.0 gallon kits. Use only as a complete mixed unit; do not break down into partial mixes.
Coverage Rates: To achieve the 0.01 perm rating, the material must be applied at 100 sq. ft. per gallon (16 mils Wet Film Thickness). Proper coverage is critical because moisture mitigation is a thickness dependent application. If spread too thin, the system may fail to isolate moisture vapor effectively.
Surface Preparation
Concrete must be clean, structurally sound, and mechanically prepared to a minimum ICRI CSP 2 to 3 surface profile. The concrete must be free of wax, grease, loose coatings, curing compounds, and dust.
Note: Acid etching is not a professional installation procedure and should not be used in place of mechanical grinding or shot blasting. It does not create a consistent surface profile and may void manufacturer warranties.
Mixing Instructions
Thoroughly pre-mix Part A before adding Part B. Combine both components and mix for 2 to 3 minutes using a slow-speed drill and paddle mixer. Scrape the sides and bottom of the mixing container during mixing. Do not mix by hand. Do not mix at high speeds, as whipping air into the material can create bubbles, pinholes, and surface defects.
Application Instructions
Apply VaporSolve LP immediately after mixing. Spread the product with a squeegee and back-roll with a quality solvent-resistant 3/8-inch nap roller cover.
The material must be rolled twice to achieve proper substrate wetting and to ensure a pinhole-free seal. Use a North-South and East-West rolling pattern to distribute the product evenly across the prepared concrete. Recoat within the 12–24 hour window. If the 24-hour window is exceeded, you must abrade the surface with 80–100 grit until it is uniformly gloss-free and dust-free before proceeding.
Common Frequently Asked Questions
Can I use this on "Green" concrete?
Concrete typically needs to cure for 28 days before coating. While VaporSolve LP can handle high humidity, it is still recommended to wait for the concrete to stabilize. If you are on a fast-track construction schedule, please contact us to discuss the specific age of your slab before proceeding.
Why is the Perm rating so important?
A perm rating measures the rate of water vapor transmission. VaporSolve LP’s 0.01 perm rating reduces moisture vapor transmission to near zero, helping prevent failure of moisture-sensitive flooring systems installed above it.
What happens if I see "Pinholes" after application?
Pinholes occur when air escapes the concrete as the epoxy cures. This is common on porous slabs and should be expected in some cases. If you see pinholes after your first coat, you must apply a second tight coat. A single pinhole can allow moisture vapor to pass through and eventually cause a failure in the finished flooring system.
Can I use this as my final garage floor finish?
No. VaporSolve LP is a functional industrial resin. It is not UV stable and is not designed for aesthetics. It must be covered with a pigmented epoxy, decorative flake system, or appropriate topcoat.
Do I need to sand before my next coat?
If you apply your next layer within the 12 to 24 hour recoat window, no sanding is required. If you wait longer than 24 hours, the surface becomes too hard for a chemical bond and must be sanded with 80–100 grit to create a mechanical profile.
Can I use Pigmented VaporSolve LP directly on concrete?
Pigmented VaporSolve LP is designed to be applied over VaporSolve Primer. If you are applying directly to properly prepared concrete without a primer, use the clear version.
Why can't I split the kits into smaller batches?
The mix ratio for moisture mitigation products must be exact to maintain the permeability rating. Measuring by eye or in small batches leads to errors. Even small mix inaccuracies can create weak spots that allow moisture to pass through, leading to system failure. Always mix the full kit as supplied.
