Self Leveling Flooring Underlayment

Product Announcement from KOSTER American Corporation

Self Leveling Flooring Underlayment-Image





KOSTER VAP-1® LEVEL PRO-FINISH is a rapid curing, trowel-applied underlayment for thin-finish applications. It is a polymer modified material and may be applied onto a variety of substrates such as the KOESTER MOISTURE VAPOR MITIGATION SYSTEMS, concrete, etc. It accepts all major floor coverings and is compatible with most adhesives.

For installations onto smooth, non absorbent substrates such as KOSTER VAP-1® SYSTEMS, as well as absorbent substrates such as concrete that are properly prepared, use the VAP-1® 06 PRIMER.

LEVEL PRO-FINISH is mixed with water only and may be troweled from a feather edge up to 1/2" thick in one layer.


The VAP-1® LEVEL PRO-FINISH Trowelable Underlayment creates the perfect subfloor demanded by the next generation of today's floor covering systems. When mixed only with water to a cream like consistency all cracks, gouges, dings, and ridges become a smooth surface. VAP-1® LEVEL PRO-FINISH Trowelable Underlayment may be installed up to 1/2" thick to compensate for deeper irregularities such as thresholds etc. it results in a true ultra thin finish, repairing nearly all types of interior subflooring such as concrete, wood, terrazzo, and ceramic tile.


> No large aggregate, resulting in ultra-thin smooth finish.

> Exceptional bond-polymer modified.

> Ideal for flash patching and skim coating.

> Low in place cost due to excellent coverage.

> Rapid installation of floor covering.

> Compatible with most adhesives

> Mixed only with water.

> May be installed up to 1/2" thickness without cracking.

> No offensive odor, free from proteins.

Surface Preparation

Surfaces to receive VAP-1® LEVEL PRO-FINISH must be sound, clean and absorptive, free of curing agents, oil, grease, paint, loose particles or any other contaminant that may weaken the bond. Always use VAP-1® 06 PRIMER prior to the application of the VAP-1® LEVEL PRO-FINISH. Use the VAP-1® 06 PRIMER for smooth non-absorbent surfaces such as VAP-1® 2000, VAP-1® 2000 FS, VAP-1® pH or other non-porous substrates as well as absorbent substrates such as concrete. DO NOT ACID ETCH! Joints must be reflected and

honored through the applied underlayment. Any weak concrete surfaces must be prepared by mechanical means to obtain a sound surface. DO NOT CLEAN SUBSTRATE WITH CHEMICALS. DO NOT APPLY OVER ADHESIVE RESIDUE.


Mix only the amounts of VAP-1® LEVEL PRO-FINISH that can be placed within 15-20 minutes at 70º F (21º C). Higher temperatures will shorten working time and coller temperatures will prolong it. Place 2-2 ½ qts. (1.9-2.4 L) of clean potable water into a mixing container and then add 10 lbs. of VAP-1® LEVEL PRO-FINISH, mixing to a lump-free, creamy consistency. A mechanical mixer such as a paddle and 1/2" heavy-duty drill will result in a better consistency and save time. Do not re-temper or over mix, entraining excess air. Smaller quantities should be mixed by hand.


Use a straight edge steel trowel when applying VAP 1® PRO-FINISH to a properly prepared surface forcing the material into all voids. There is no minimum thickness required. VAP 1® LEVEL PRO-FINISH may be applied from paper thin to 1/2" in one lift without cracking. However; If applied onto substrates such as KOSTER VAP 1® SYSTEMS receiving water based adhesives, a minimum thickness of 80 mils (2mm) is absolutely essential to absorb the excess water to avoid entrapment.

Substrate Priming

Do not prime substrates when surfaces are below 50ºF. Provide dry and clean surfaces. Do not install VAP-1® LEVEL PRO products without using the VAP-1® 06 PRIMER first. Apply the VAP-1® 06 Primer in a way as to avoid a heavy thick coat (refer to the VAP-1® 06 Primer data sheet) as this may result in cracks in the underlayment.

For additional information, please contact Koester American Corporation at 757-425-1206.

Flooring Installation

LEVEL PRO-FINISH is ready to receive floor coverings in approx. 20-30 minutes unless moisture sensitive adhesives are used. For moisture sensitive adhesives allow VAP 1® LEVEL PRO-FINISH to cure for a minimum period of 16 hours. Always use VAP 1® 06 PRIMER with VAP 1® PRO-FINISH in conjunction with KOESTER VAP 1® SYSTEMS.


Per 10 lbs. (4.5 kg.)

Nominal Thickness

Approximate Coverage

1/8" (3 mm) 33 ft2

1/4" (6 mm) 17 ft2

As Skim Coat:

225 ft2

All coverage rates are estimates and are dependent upon substrate characteristics.

Clean Up

Clean tools with water while mortar is still moist.


10 lb. (4.54 kg) resealable pails.

25 lb. (11.36 kg) moisture resistant bags.

(100 bags per pallet)


Always keep in cool, dry place, unexposed to sunlight and tightly re-seal container.

Shelf Life

12 months when stored properly in original unopened container.

For Best Results

> Only install LEVEL PRO FINISH on interior projects.

> Install LEVEL PRO FINISH between 40º F and 100º F.

> Do not install over gypsum based surfaces.

> Do not over-water, retemper, or add additives.

> Always install a test area insuring suitability for intended use.

> Not a wearing surface. Must be covered with flooring.

> Rely upon floor covering manufacturer for directions concerning maximum allowable moisture content of subfloor, adhesive selection, etc.

> Do not fill cracks and joints with LEVEL PRO FINISH.

> Avoid standing water. Avoid exposure to moisture or moisture vapor.

> Protect from freezing for a minimum of 24 hours.

Material Properties:

Working time at 70º F (21ºC) 20 minutes

Compressive Strength ASTM C 109 (Air Cured)

24 hours

2100 psi (14.5 MPa)

7 days

2800 psi (19.3 MPa)

28 days

4700 psi (32.4 MPa)

Working Time: 20 minutes at 70º F (21º C)

Initial Set Time (ASTM C 191): 25 minutes at 70º F (21º C)

Final Set Time (ASTM C 191): 30 minutes at 70º F (21º C)

The above listed values may vary slightly from project to project, depending on environmental and substrate conditions.