Background: Toilet in hall bathroom on 2nd floor; Toilet flange was cracked; Repaired by my contractor: Cut 3” PVC pipe to remove the broken flange. Used insert flange that fit inside the 3” PVC pipe, interior diameter 2.5"; there is a 90-degree elbow immediately beneath the toilet, After the flooring was laid, flange height about flooring = 3.16/16” = 0.1975”
Toilet installation: Done by my plumber,toilet did not rock.
Toilet starts to leak 2 months later: It leaks out the side of the toilet only when it is flushed. We have not had any toilet clogs where I needed to plunge the toilet.
Photos below: Wax ring after I pulled the toilet. Repaired toilet flange with insert, mounted on top of sub-floor.
Here is a picture of the toilet leaking out when flushed, and picture of toilet flange insert pulled and sub-floor is soaked.
Pulled up LVP flooring. Sub-floor soaked.
Opened up sub-floor. Very little water leaked down (luckily caught this leak quickly). There is a 90-degree elbow right beneath toilet.