The best floor for housing by the roadside in the United States is typically the high floor. This is due to several factors that enhance the quality of life and property value. High floors offer several advantages over low floors, including better views, less noise, and greater privacy. According to a study by the National Association of Home Builders (NAHB), homes on higher floors tend to have higher resale values due to the aforementioned benefits.

High floors provide better views, which can significantly enhance the aesthetic appeal of a home. This is particularly important in urban areas where skyline views are a desirable feature. Additionally, higher floors are less likely to be affected by noise pollution from roads and traffic, as they are further from the source. The NAHB study found that noise pollution is a major concern for homeowners, with 70% of respondents indicating that it negatively impacts their quality of life.

Privacy is another key advantage of high floors. Residents on higher floors are less likely to be seen from the street, which can be particularly appealing for those who value their privacy. This is especially true in neighborhoods with a high density of homes or in areas where there is a lot of foot traffic.

Moreover, high floors often offer more natural light and ventilation, which can lead to lower energy bills and a healthier living environment. Natural light has been shown to have numerous health benefits, including improved mood and sleep quality. According to the U.S. Department of Energy, homes with ample natural light can save up to 10% on energy costs.

While high floors offer numerous benefits, it's important to consider the potential drawbacks. High floors may be more expensive to maintain due to the increased cost of utilities and potential repair issues. Additionally, residents may have to deal with higher elevator wait times and may be more susceptible to extreme weather conditions, such as strong winds or heavy rains.

In conclusion, the best floor for housing by the roadside in the United States is typically the high floor. This is due to the better views, reduced noise pollution, enhanced privacy, increased natural light, and potential for lower energy bills. However, it's important to weigh these benefits against the potential drawbacks, such as higher maintenance costs and potential exposure to extreme weather conditions.