Lancaster, Pa.—Armstrong Floor Products is proactively addressing high-moisture installations with a line of moisture resistant adhesives that increase 
product quality and reduce failures due to moisture. These new adhesives allow for installation of select Armstrong resilient flooring products when a relative humidity reading of up to 90% as calculated by an in-situ probe is measured on concrete slabs.
Three adhesives—S-515 Vinyl Composition Tile, S-521 BioBased Tile and Vinyl Composition Tile S-543 Sheet Flooring and Luxury Vinyl Tile—increase allowable subfloor moisture for installing Armstrong floors. These adhesives were engineered to retain their bond strength when installed on concrete slabs with excessive moisture, providing installers a reliable, time-saving installation option from a trusted brand.
“Moisture in concrete subfloors is one of the major causes of adhesive failures today, costing millions of dollars in damage,” said Stephan J. Chmielewski, product manager, Installation, Maintenance & Accessories, Armstrong. “If a flooring failure is the result of moisture, you have to pull up the floor and start over.”
Potential causes of failure can include fast track construction, a high water-cement ratio or simple cost cutting during construction. According to Armstrong, while 90% of the industry’s commercial litigation cases focus on water-related damages, only about 1.5% of the typical building budget is dedicated to waterproofing and related issues. Armstrong adhesives provide a broader range of installation options over concrete to help address these concerns.
The moisture resistant adhesives increase the allowable subfloor moisture for installing Armstrong VCT, BBT, LVT and vinyl-backed sheet flooring products over concrete slabs. A relative humidity reading of 90%, a 20% increase above the industry standard[1] as measured by an in-situ probe and a pH level of up to 11, is allowed.
“Tests conducted on specific Armstrong products installed with S-515, S-521 and S-543 adhesives by an independent lab demonstrated consistent tensile bond strength when applied to high-moisture slabs,” Chmielewski said. “Moisture and bond test performance is so effective these adhesives actually may eliminate the need for more expensive moisture mitigation systems”.
A 5-year warranty covers S-515, S-521 and S-543 installations for Armstrong products on high-moisture slabs. Installation is backed by the Armstrong Guaranteed Installation System, “the name customers know and trust for superior installation,” said Chmielewski.
Proven, trowel-on method provides clean, more consistent application.
The standard trowel-on method covers subfloors more consistently than spray-on adhesives that may be applied thicker in some areas and thinner in others. A consistent adhesive application is desirable for predictable performance, including working time and bond strength.
Troweling provides visual and tactile verification that subfloors are free from debris that could later telegraph through floor coverings after installation, avoiding potential installation claims,” explained Chmielewski. “Adhesives applied via troweling trap any surface dust, creating a clean dust-free environment. By contrast, spray-on methods dispense dust into the air, where particles can be redeposited onto other interior finishes. Trowel-on adhesive methods keep projects running smoothly and on-time.”
Online information can be found at Armstrong Floor Expert Database, floorexpert.com. This database is designed to help dealers, installers and contractors find useful data on Armstrong products, installation procedures and warranties.