Final answer:
Sheathing and subflooring should be installed with a gap of about 1/8 inch between the ends of adjacent panels and at the sides to allow for expansion and contraction.
Step-by-step explanation:
When installing sheathing and subflooring, it is recommended to leave a gap of about 1/8 inch between the ends of adjacent panels and at the sides. This allows for expansion and contraction of the panels due to changes in temperature and humidity. The gap also helps to prevent buckling and warping of the panels.