What is the minimum lap requirement for rabbeted horizontal lap siding?

The minimum lap requirement for rabbeted horizontal lap siding is 1/2 inch. This measurement is critical for ensuring proper water drainage and preventing moisture accumulation behind the siding, which can lead to potential damage to the structure. Having a 1/2 inch lap helps to direct rainwater off the edges of the siding and provides a barrier to wind-driven rain, enhancing the durability and effectiveness of the siding system.

Additionally, the 1/2 inch lap allows for slight variations in installation and weather conditions, accommodating natural expansion and contraction of materials over time. Proper understanding of lap requirements is essential for contractors, as it directly influences the longevity and performance of the siding installation.