The 10 most common plumbing mistakes DIYers make · Overtightening connections · Wrapping threaded tape backwards or using the wrong tape · Use. Overtightening supply pipes, pipes, and toilet fittings and screws is one of the most common mistakes made by DIYers. If you crank too tightly a galvanized or black pipe, coupling, T-elbow, or elbow, you run the risk of breaking the connection. The crack may not occur immediately, but excessive force can break the pipe weeks later and cause a flood.
Learn how to protect your home with ventilation grilles. PTFE tape (commonly called Teflon tape) must be wound around the threads clockwise to work properly. However, many DIYers wrap it upside down so that the tape unrolls from the threads as they tighten the attachment. This defeats the whole purpose of using adhesive tape, since it cannot seal if it is not embedded in the threads.
Saddle drill valves do not meet current plumbing codes. However, they still come packaged in some humidifier kits for icemakers and ovens, and you can still buy them at home care centers. So DIYers keep installing them. Saddle valves are known to leak, especially after being subjected to the shutoff cycle and opening many times.
As they are usually installed in secluded places, the leak can go unnoticed for months and cause mold problems. Discard the saddle valve and install a ball valve instead. If you've already installed a saddle valve, remove it and install a ball-type shutoff valve now, before the old valve starts to leak. January 16, 2025 by Carolyn Casper.
