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The Choice of Professionals ™. Seth Pevarnik Manager of Technical Service. Self-leveling & Patching Materials Categories of flooring failure. Proper methods of substrate preparation. Selection of Self-leveling & Patching materials. Failure modes for Self-leveling & Patching materials.
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The Choice of Professionals™ Seth Pevarnik Manager of Technical Service
Self-leveling & Patching Materials Categories of flooring failure. Proper methods of substrate preparation. Selection of Self-leveling & Patching materials. Failure modes for Self-leveling & Patching materials.
WHY FLOORS FAIL . . . • 85% OF ALL FLOORING INSTALLATIONS FAILURES ARE DUE TO SOME ASPECT OF SUBFLOOR PREPARATION!
THREE MAIN CATEGORIES OF FAILURE • EXCESSIVE MOISTURE VAPOR EMISSIONS • IMPROPER SUBSTRATE PREPARATION • IMPROPER USE OF “PATCH”
CONCRETE & MOISTURE Every manufacturer of floor covering has specific statements regarding the moisture content of the substrate to receive their flooring and the proper method of moisture testing.
CONCRETE & MOISTURE Excess moisture in concrete slabs causes a variety of flooring failures, disrupting building operations and necessitating expensive repairs. Consequences can be particularly serious in schools, hospitals and commercial installations where the loss of use of certain facilities, and hazardous conditions can jeopardize people’s safety, not to mention loss of business.
When Moisture Testing Fails • Refuse to install • Wait for the concrete to dry • Fix the problem • Accept a sign off from the general contractor!?
Subfloor Preparation • ASTM F 710 – Standard Practice for Preparing Concrete Floors to Receive Resilient flooring
ASTM F 710 • Available from the American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken PA 19428; [610] 832-9500; www.astm.org • Preparation of concrete slabs to receive resilient flooring
ASTM F 710 (cont.) • Dry, clean, smooth, and structurally sound. • Free of dust, solvent, paint, wax, oil, grease, residual adhesive, adhesive removers; curing, sealing hardening, or parting compounds; alkaline salts, excessive carbonation or laitance, mold, mildew, and other foreign materials that might prevent adhesive bond • Calcium chloride moisture tests [ASTM F 1869]; results should be 3 pounds or less or resilient flooring manufacturer’s recommendations
ASTM F 710 (cont.) • Relative Humidity [ASTM F2170] 75% or less • Alkalinity testing; maximum pH of 10 • Don’t use adhesive removers. • Flatness requirements: ±1/8” in 10 feet • Drying time for slab: minimum of 60 to 90 days • Moisture retarders recommended under all on-grade and below-grade concrete floors.
Concrete Subfloor Preparation • Smooth, clean, dry • Free of ALL surface treatments and contaminants
Other Contaminants • Dry Wall Mud • Paint Overspray • Oil & Grease • Asphalt or Tar
Other Contaminants (cont.) • Flooring Adhesives • On a concrete substrate only. • Not water soluble. • Scrape to a thin well bonded residue. • Asbestos Adhesive - Wet-Scrape Only! Follow the guidelines of the Resilient Floor Covering Institute and comply with state and local laws. • Resilient Floor Covering Institute 401 East Jefferson Street, Suite 102 Rockville, Maryland 20850 Telephone: 301-340-8580 www.rfci.com
Mechanical Cleaning of Concrete • Shot Blasting • Scarifying • Scabbling • Bush-Hammering • Grinding • Sand or Water Blasting
The use of sanding equipment is not sufficient to remove curing and sealing compounds from the surface of concrete!
Do not use chemicals such as adhesive removers or acid to prepare the concrete!
Adhesive Removers • The only part of our industry that recommends adhesive removers are the adhesive remover manufacturers! • The use of solvents and “removers” on concrete will result in failure! • Mechanically clean the concrete!!!
Acid Etching • Cannot be 100% certain that acid is neutralized. • Introducing a tremendous amount of water to the concrete. • Mechanically clean the concrete!!!
Other Concrete Substrates Lightweight Concrete must be structural lightweight! • Min. 3,000 psi in compressive • Min. 100 lb.cu.ft. in density
Repair of Cracks • All dormant cracks larger than hairline (1/32”) must be filled • V-out or “chase” • Fill full width and depth • Does not ensure against telegraphing in case of further movement
Joints in Concrete • Expansion / Isolation Joints • Control / Contraction Joints
Summary-failure to properly prepare a concrete substrate • Mechanical preparation not used on standard concrete • Concrete inherently weak – should have a tensile strength of at least 200 psi • Assumed no curing compound was used or that it had dissipated • Sealer remaining on concrete substrate
Summary - failure to properly prepare a concrete substrate • Used adhesive removers or acid etching • Adhesive residue too thick • Went over expansion joint • Went over moving crack • Went over isolation joint
Non-Porous Substrates Ceramic Tile – make sure tile is solidly bonded.
Non-Porous Substrates Metal • Make sure foils are solidly adhered with epoxy!
Non-Porous Substrates Epoxy Coatings If these can be removed, do so. Don’t assume they are solidly bonded.
Non-Porous Substrates Terrazzo Make certain that sealers, waxes and dressings are completely removed.
Summary - failure to properly prepare a non-porous substrate • Loose ceramic tile not removed. • Metal foil not solidly bonded. • Epoxy system flaky or disbonding. • Wax or dressing not stripped from terrazzo.
Wood Subfloors • Plywood/OSB • Solid Strip or Plank • Make sure all are structurally sound and solid and installed according to code.
Type 1 Plywood • Suitable for uses not permanently exposed to the weather. • Panels classified as Exposure 1 • are intended to resist the effects of • moisture on structural performance due • to construction delays, or other conditions • of similar severity.