Answer
Jul 11, 2025 - 11:47 AM
We always suggest and follow what Forbo says in their installation guide : https://www.greenbuildingsupply.com/cdn/shop/files/doc-IG_Installing-Marmoleum-
Cinch-LOC-Seal_v1.13-USE-2024GreenBuildingSupply.pdf?v=9781004195053798756 "Marmoleum Cinch LOC Seal can be installed on any clean, dry, structurally sound subfloor. The subfloor must be flat to within 3/32� in 6� (2.0mm in 2 meters). " It is best practice to go by the actual manufacturer words. According to the QuietWalk Plus installation : https://www.greenbuildingsupply.com/cdn/shop/files/doc-MP-Global-QuietWalkPLUS_
Installation-_USE_2024_GreenBuildingSupply.pdf?v=3492844962335458378" . If the flooring manfuacturer does not specify requirements for flatness, your subfloor must be flat within 1/8� over 6� span, or 3/16� over a 10� span. All leveling, prep work, priming, etc must be done prior to installation of underlayment."
Cinch-LOC-Seal_v1.13-USE-2024GreenBuildingSupply.pdf?v=9781004195053798756 "Marmoleum Cinch LOC Seal can be installed on any clean, dry, structurally sound subfloor. The subfloor must be flat to within 3/32� in 6� (2.0mm in 2 meters). " It is best practice to go by the actual manufacturer words. According to the QuietWalk Plus installation : https://www.greenbuildingsupply.com/cdn/shop/files/doc-MP-Global-QuietWalkPLUS_
Installation-_USE_2024_GreenBuildingSupply.pdf?v=3492844962335458378" . If the flooring manfuacturer does not specify requirements for flatness, your subfloor must be flat within 1/8� over 6� span, or 3/16� over a 10� span. All leveling, prep work, priming, etc must be done prior to installation of underlayment."
