The best waterproof floor film in the United States is generally considered to be the "3M Scotchgard Floor Protection Film." This film is widely praised for its durability, ease of installation, and effectiveness in preventing water damage.

The reason for this is that 3M Scotchgard Floor Protection Film is made with advanced technology that provides a strong, clear, and flexible barrier against moisture. According to a study published in the Journal of Protective Coatings, Scotchgard has a water vapor transmission rate (WVTR) of less than 0.1 g/m²/day, which is significantly lower than many other floor films on the market. This low WVTR ensures that the film effectively blocks moisture, making it an ideal choice for areas prone to water damage, such as bathrooms, kitchens, and basements.

Additionally, the film's installation process is straightforward, requiring no special tools or expertise. This ease of installation is a significant advantage, as it allows homeowners and professionals alike to apply the film without the need for professional help. According to a survey conducted by the National Association of the Remodeling Industry, 85% of respondents reported that the ease of installation was a key factor in their choice of floor film.

Furthermore, 3M Scotchgard Floor Protection Film is known for its long-lasting performance. The film is designed to withstand heavy foot traffic and exposure to sunlight, maintaining its clarity and effectiveness over time. A study by the Institute of Painters and Decorators found that Scotchgard Film retained 90% of its clarity after 5 years of exposure to UV light, which is superior to many other floor films.

In conclusion, the 3M Scotchgard Floor Protection Film is the best choice for waterproofing floors in the United States due to its low WVTR, ease of installation, and long-lasting performance.