Hello. I think it's better than asking such questions on the forum, refer to this site
https://pomplumbing.ca/domestic-water-heating-cooling-riser-replacement-including-engineer-drawings/ where they will tell you in detail about everything. The most important thing that you should know is that masters of their craft work here. They did the plumbing for me so professionally that I didn’t even have time to blink an eye, and that was the most important thing. Moreover, it's great that here you can consult on any issue, which also gives confidence.