Homeowners without sufficient DIY skills may risk the safety of their property, claim Yorkshire Water.
Richard Kershaw, sewer flooding manager at the water company, has warned that people who have not taken plumbing courses or tiling courses are more likely to block their kitchen and bathroom drains with unsuitable substances due to a lack of awareness.
Yorkshire Water claim to have discovered tools such as hammers, chisels and saws in sewers across the region as well as unwanted building materials like wood, bricks and sand.
"We understand that people want to get everything cleared up quickly after a long battle with a paint brush and four walls, but we'd ask them to think twice before using their drains and our sewers to dispose of the evidence," Mr Kershaw said.
DIY enthusiasts would not face the problems of incorrect waste disposal if they took part in tiling courses, claimed Mr Kershaw.
The water company revealed that tiling grout, paint, varnish and solvents cause the biggest problems to their sewage works, which is often exacerbated during bank holiday weekends when more people take part in DIY.
"Substances such as tiling grout can cause a huge problem as they harden and build up in our sewers, which can lead to blockage and potentially result in sewage flooding people's homes which is the last thing anybody wants at any time of the year," he added.
Homeowners can avoid costly repairs by taking plumbing courses and learning how to deal with DIY debris.
"And if people don't block our sewers, they risk blocking their own drains, which they are responsible for clearing, often at quite a cost. Our message is very simple: Bin it, don't flush it," added Mr Kershaw.
Serious damage can be caused to properties by homeowners who lack the basic skills which can be learned on plumbing courses, according to Yorkshire Water.
Yorkshire Water has produced an educational video which demonstrates the dangers of putting unsuitable items down a sink.
A fire extinguisher, chair, desk, false teeth, prosthetic limb and even a kitchen sink are some of the extreme items which Yorkshire Water have removed from its sewers and sewage treatment works.