WLFI Industry Guidelines & Reporting Standards 2 — Questions and Answers
Question 1: Which NWFA document provides the primary installation guidelines for solid hardwood flooring in the United States?
- ANSI A108.01
- NWFA Installation Guidelines (Correct answer)
- ASTM F710
- ICC A117.1
Correct answer: NWFA Installation Guidelines
The NWFA (National Wood Flooring Association) Installation Guidelines is the primary industry document governing solid hardwood flooring installation in the US.
Question 2: When documenting subfloor flatness in an inspection report, what tolerance does NWFA generally accept for most hardwood flooring installations?
- 3/16 inch in 6 feet
- 3/8 inch in 10 feet
- 1/4 inch in 10 feet (Correct answer)
- 1/8 inch in 6 feet
Correct answer: 1/4 inch in 10 feet
NWFA guidelines specify that subfloors should be flat to within 3/16 inch in 10 feet, or 1/8 inch in 6 feet, for most hardwood installations.
Question 3: According to industry reporting standards, which section of a flooring inspection report should describe the conditions at the time of inspection?
- Conclusions and Recommendations
- Limitations and Disclaimers
- Observations and Site Conditions (Correct answer)
- Standards of Practice
Correct answer: Observations and Site Conditions
The Observations and Site Conditions section documents what the inspector found at the time of the inspection, including environmental data and visible defects.
Question 4: ASTM F2170 is referenced in flooring inspection reports primarily to address which issue?
- Adhesive bond strength
- In-situ relative humidity testing of concrete slabs (Correct answer)
- Surface hardness of laminate wear layers
- Coefficient of friction for slip resistance
Correct answer: In-situ relative humidity testing of concrete slabs
ASTM F2170 is the standard test method for determining relative humidity in concrete floor slabs using in situ probes.
Question 5: When a flooring inspector identifies a defect caused by improper acclimation, which party is typically identified as responsible in a compliant report?
- The flooring manufacturer
- The installer (Correct answer)
- The building owner
- The raw materials supplier
Correct answer: The installer
Acclimation is an installer responsibility; if flooring was not properly acclimated per manufacturer and NWFA guidelines, the installer bears responsibility.
Question 6: Which standard provides guidelines for acceptable moisture content levels in wood subfloors relative to the finish flooring being installed?
- NWFA Technical Guidelines
- OSHA 29 CFR 1926
- ANSI/NWFA 1-2011 (Correct answer)
- ICC R506
Correct answer: ANSI/NWFA 1-2011
ANSI/NWFA 1-2011 (Wood Flooring Installation) specifies acceptable moisture content differentials between subfloor and finish flooring.
Question 7: In a WLFI inspection report, photographs are considered best practice for which primary reason?
- They replace the need for written descriptions
- They provide objective visual evidence supporting written findings (Correct answer)
- They satisfy local building code permit requirements
- They establish the inspector's liability protection only
Correct answer: They provide objective visual evidence supporting written findings
Photographs provide objective, visual documentation that supports and corroborates the written findings in the inspection report.
WLFI Industry Guidelines & Reporting Standards 2
Which NWFA document provides the primary installation guidelines for solid hardwood flooring in the United States?