This year marks the eighth anniversary of FCI’s annual Underlayment and Subfloor Preparation Reference Guide, which has proved to be very popular with our readers. While the subject of underlayment and subfloor preparation might seem to be somewhat limited in scope, this is hardly the case. Problems related to improper subfloor preparation continue to multiply each year, with millions of dollars in damage as a result.

Sadly, most of these problems are preventable when correct installation methods are followed. In order to prevent these types of failures, installers need to pay careful attention to all aspects of the jobsite prior to starting any installation. Standing water and mold in HVAC systems should raise a red flag that moisture issues are likely. Before starting any installation, it is critical to make sure that the subflooring is ready to have flooring installed over it. There are now countless specialized products to help installers ensure that subfloors are clean, flat and dry enough to install flooring over. However, in order to use them effectively, installers need to take the time to learn about the latest products and installation methods.

With that in mind, this special issue of FCI is jam packed with helpful articles to help installers get up to speed on the correct methods of underlayment selection and installation, as well as subfloor preparation. Wood flooring is especially vulnerable to moisture issues related to subflooring, a subject that is addressed by FCI’s resident wood expert Mickey Moore in his article, “Wood Flooring Installation and Framed Construction.” Another category of installations that are experiencing numerous failures are those that are done over lightweight concrete and gypsum-based subfloors. Jon Namba explores the best methods for these types of installations in his article, “Installing Flooring Over Lightweight Substrates.” Moisture testing is a perennial issue for installers, as recommended testing methods vary depending upon the type of flooring to be installed. Resilient flooring expert Christopher Capobianco details the latest updates to the calcium chloride test as well as the proper methods for relative humidity testing, and explains how both methods are complementary to ensure the best substrate prior to installation. These are just a few of the highlights of this special issue; be sure to check out all the articles and columns, as well as the Underlayment and Subfloor Preparation Reference Guide, a handy listing of the latest underlayment and subfloor prep-related products and companies. If there is a subject you would like to see addressed in FCI, be sure to email us your comments and suggestions.