Transcript Document
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.
CELL PHONES
Industry Studies
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”
Moisture
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.
Substrate Preparation The Key to Success!
Concrete
Concrete Subfloor Preparation
Smooth, clean, dry
Free of ALL surface treatments and contaminants
Efflorescence
“Effervescence”
Efflorescence
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
Shot blasting a concrete surface
Scarifying
Grinding
Scabbling
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
Cracks
Concrete Crack Repair
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
Wood Subfloors
Wood Subfloors
Plywood/OSB
Solid Strip or Plank
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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.
All wood must be:
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Prepared to bare wood
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Surface may require primer and the use of a lath mesh.
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Additive may be required to further accommodate movement.
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Joints must be filled full width and depth.
Summary- failure to properly prepare a wood subfloor
Wood not structurally sound
Inadequate fastening of wooden subfloor
Didn’t use lath or additive as required
Preparation of Substrates using Self leveling & Patching Materials
Hang in there!
Categories of Materials Used Gypsum-based Portland cement-based Self-leveling Trowel grade
Use a Portland cement based material
Can be used on all grade levels
Can handle periodic moisture
Have similar compressive strengths to that of the structural concrete – 3000 to 4000 psi
When to use a Trowel grade or Self-leveling Material
Do not base it on square footage.
Do not base it on substrate.
Do not base it on the thought that trowel grade materials dry faster than self-leveling materials.
When to use a Trowel grade or Self-leveling Material
Look at the thickness needed to achieve the required flatness or level of the concrete.
1/8” or less use a patching material
1/8” or greater float the substrate with a self-leveling material.
Look at the whether a slope is required .
Selecting a Self-leveling Material
Versatility
Installs over any common substrate – concrete, non-porous, wood, metal & adhesive residues.
Installs to any thickness.
Install flooring in 16 hours – even at any thickness.
Some Self-leveling materials can have flooring installed in 2 hours.
Selecting a Self-leveling Material
Not all Self-leveling materials are the same.
Compare Apples to Apples.
Some materials may be limited to certain substrates.
Some materials may be limited in thickness.
Some materials may take longer to dry – 2 to 3 days.
Selecting a Self-leveling Material
Select a material that fits the job.
Select a material that has a track record.
Select a material that is Portland Cement-based.
Select a material that is recommended by the flooring manufacturers.
Selecting a Patching Material
Decide whether a skim coating or ramping and sloping material is needed
Selecting a Patching Material
Ramping/Sloping Material
Fluid consistency that is easily screeded but can maintain slope.
Installs up to 3”
Install flooring quickly – even at 3” in thickness.
Selecting a Patching Material
Skim coating material
Unsanded
Installs over any common substrate – concrete, non-porous, wood, metal & adhesive residues.
Dries quickly
Has excellent coverage.
Selecting a Patching Material
Not all Patching materials are the same.
Once again, compare Apples to Apples.
Some materials may be limited to certain substrates.
Some materials may require an additive.
Some materials may be limited in thickness.
Some materials may take longer to dry – 1 to 3 days.
Coverage per pound may vary from on product to another.
Selecting a Patching Material
Select a material that fits the job.
Select a material that has a track record.
Select a material that is Portland Cement-based.
Select a material that is recommended by the flooring manufacturers.
What can go Wrong?
What can go Wrong?
Improper Product Selection
Improper Mixing
Improper Installation
Surface defects
Compatibility is critical!
Improper product selection
Substrate not appropriate for the Self leveling or patching material.
Gypsum product used on or below grade.
Used self-leveling material instead of trowel-grade material or the reverse.
Applied too thick.
Improper Mixing of the Self leveling or patching material
“Over-watering” – the number one cause of failures when it comes to patching materials!
Didn’t use additive as required.
Improper Installation of the Self leveling or patching material
Inadequate drying time allotted.
Primer applied too thick.
Wrong primer for type of substrate.
Surface defects not detected prior to installation of flooring
Surface defects not detected prior to installation of flooring Flatness tolerance not achieved
Don’t have time to do it right!
Discipline!
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Free Training Seminars – go to www.ardex.com
Website/Phone/Etc.