Q: Why cant I just use couplings and pvc piping?
A: You can not buy pvc couplings that will fit on a cast iron pipe (inside or out) that will convert to fit onto pvc.
Q: What about the no hub couplings that have hose clamps on either sides?
A: When using those you have to use a bigger lead boot to fit it, which would then cost more than using a Tubos and you would have to squeeze all the extra lead into the smaller existing pipe. Plus send a worker to pick up the couplings, Tubos comes with all your supplies to the job.
Q: What if the pipes existing on the roof are pvc already?
A: You will still have to use outside couplings, therefore using a bigger more expensive boot. Also, pvc is a new method for plumbing ventilation, 99% of your reroof jobs will be cast iron.
Q: Cant I just get two different size pvc pipes and glue them together like what appears to be with Tubos?
A: The inside and outside diameter of Tubos is one of a kind. This size pvc can not be found anywhere else. The purpose for our measurements is so the insert can fit into a cast iron pipe and pvc while the outer part of the Tubos is wide enough to sit ontop of a pvc pipe without falling down into it.
If you still have questions about our product, please call or email us so we can have an opportunity to answer them. Maybe you do have a better way, we have an extensive roofing background, we would love to know about it, because we don't believe it exists.