All of our installers are fully trained and rgii registered gas installers who pride themselves on quality of their work and health & safety standards. If you are constantly plagued with clogged or slow drains, have a plumber inspect the plumbing to determine if the drain line was properly designed and installed both drain pipe venting and slope effect how well drains work. Nichola from burton-on-trent on 31st march 2014. Forthside way stirling fk8 1qz. Installing.