On Oct 24, 5:40*pm, Aaron Fude wrote:
Hi,

My carpenter just told me that if I am having a skylight put in
between two rafters, I should double up each rafter because the hole
in the wall weekens the roof. Do you agree with that?

Thanks,

Aaron

If the roof is on engineered trusses, modifications are needed. Allay
your doubts by getting sound professional advice (architect) and
asking questions at your building inspection department. We can't give
you good advice based on so little information. Good luck.

Joe