When installing underlayment, what size gap should be left between it and the wall?

When installing underlayment, leaving a 1/4 inch gap between it and the wall is important for several reasons. This gap allows for the natural expansion and contraction of both the underlayment and the flooring material due to changes in temperature and humidity. If the underlayment is installed too close to the wall, it can create pressure points that lead to buckling or warping of the flooring over time.

Additionally, this gap provides a space for any potential moisture accumulation, which is particularly relevant in areas where humidity levels can vary. By leaving a 1/4 inch gap, the installation remains compliant with industry standards, ensuring the longevity and performance of the floor covering. This gap is optimal for most underlayment materials, promoting proper airflow and drainage, which can help to prevent mold and mildew issues in the future.