7 Critical Mistakes in Bathroom Renovation (That Will Cost You a Lot)

Planning a bathroom renovation? Here are seven mistakes that can turn your bathroom into a source of constant problems (and costs). We break down each one and explain how to avoid them.

Main points from the article:

• Waterproofing is more important than beautiful tiles;

• Start the renovation by replacing pipes if they are over 15 years old;

• Plan storage systems before starting the renovation;

• Ventilation must be forced;

• Cost-cutting on plumbing leads to leaks;

• You need at least two types of lighting;

• All outlets must be protected from moisture.

Ignoring waterproofing

"Why do I need waterproofing if water will go down the drain?" — many think. Then neighbors below come to complain about wet spots on the ceiling.

How to do it right:

• Apply waterproofing to the entire floor surface;

• Extend it onto walls at least 15 cm;

• Pay special attention to joints between floor and walls;

• Don’t forget waterproofing around pipe exits;

• Use special waterproofing tape for corners.

Old pipes behind new tiles

Often people delay replacing pipes to save money. But after a year, they have to break the new tiles to reach the corroded pipe.

How to do it right:

• Replace pipes if they are over 15 years old;

• Install modern polypropylene pipes;

• Install access panels for pipe inspection;

• Replace all gaskets in joints;

• Install new ball valves.

Underestimating storage systems

In the pursuit of visual beauty, functionality is often forgotten. As a result, a beautiful bathroom ends up full of bottles, and towels have to be stored in the bedroom.

Proper planning:

• Plan storage before starting the renovation;

• Provide space for household chemicals;

• Design shelves for towels and bathroom essentials;

• Don’t forget a toilet paper holder;

• Consider installing a cabinet under the sink.

Design: Ekaterina Kotalyevskaya

Ventilation problems

"Ventilation works fine already" — the most dangerous misconception. Without proper ventilation, even the most expensive renovation will soon be covered in mold.

How to do it right:

• Check natural ventilation before renovation;

• Install a humidity sensor fan;

• Ensure fresh air supply (gap under the door at least 1.5 cm);

• Regularly clean the ventilation grille;

• Do not fully block the ventilation duct with a cover.

Cost-cutting on plumbing

Purchasing cheap plumbing and saving seems reasonable. Until the first leak or failure in a month.

Where you shouldn't cut costs:

• Faucets (especially built-in ones);

• Toilet installation system;

• Traps and drains;

• Shower system.

Bathroom curtain or glass partition hardware.

Incorrect lighting

A dim bulb above the entrance is a poor choice. In such lighting, it’s hard to shave or apply makeup.

Proper lighting scheme:

• Main overhead light (IP44 or higher);

• Backlighting for the mirror area;

• Use fixtures with moisture protection;

• Color temperature of 4000K for natural lighting.

Install a switch near the entrance.

Design: Alina Rogovskaya

Mistakes in electrical work

"A socket near the sink is convenient for a hairdryer." But this is a direct safety violation that can lead to tragedy.

How to do it right:

• Use only moisture-proof outlets;

• Place outlets at least 60 cm from water sources;

• Install a GFCI for the bathroom;

• Ensure proper grounding;

• Check all connections before final finishing.

Bonus: Tips for Long-Lasting Renovation

• Make the floor slope toward the drain or outlet;

• Use grout with anti-fungal additives;

• Seal all joints with sanitary silicone;

• Keep instruction manuals for all plumbing fixtures;

• Leave a tile surplus (at least 10% of total area).

Cover: Design project by Julia Tazulakh, JTRoom