When sleeving through a foundation, the sleeve must be how much larger than the pipe?

When sleeving through a foundation, the sleeve must be 2 pipe sizes larger than the pipe. This requirement ensures that there is sufficient space between the pipe and the sleeve, allowing for any movement or expansion of the pipe due to temperature changes or pressure. Additionally, this extra room helps prevent friction and wear on the pipe, which could potentially lead to leaks or other plumbing issues over time.

The larger sleeve also facilitates the installation of insulation materials if needed and accommodates any future modifications or maintenance that may be necessary. Having a sleeve that is adequately oversized, in this case, by 2 pipe sizes, promotes better stability and longevity of the plumbing system as a whole, which is crucial for structural integrity and system performance in plumbing applications.