Bathroom Renovation: A Step-by-Step Guide From Planning to Finish

The bathroom is the most expensive room in an apartment per square meter. Water, electricity, ventilation and finishes all meet here, and mistakes don't show immediately but months later — as a leak to the neighbors, mold behind the tiles or cracked grout. That's why a bathroom renovation needs especially careful planning. Let's go through every stage, from the idea to hanging the mirror.

Step 1. Planning

Define How It Will Be Used

• How many people will use the bathroom? Do you need two sinks?
• Bath or shower? Are there small children who are easier to bathe in a tub?
• Will there be a washing machine and dryer?
• Do you need storage for cleaning products, towels and cosmetics?

Ergonomics

Minimum clearances for comfort:

• in front of the toilet — 60 cm of free space, 20–25 cm from its axis to the side walls;
• in front of the sink — 70 cm;
• shower entrance — from 60 cm;
• sink height — 80–90 cm, depending on height.

Redevelopment

If you plan to enlarge the bathroom into the corridor or merge it with the toilet, remember: "wet" zones can't be placed above neighbors' living rooms. More in apartment redevelopment.

Step 2. Demolition and Inspection

Remove old tiles, sanitaryware and pipes. After demolition, assess:

• the risers — if they're old, agree replacement with the condominium association and neighbors;
• walls and floor — cracks, damp, mold;
• the ventilation duct;
• the room's geometry.

Step 3. Ventilation

Without effective ventilation, even perfect waterproofing won't prevent condensation and mold. The US Environmental Protection Agency (EPA) names moisture control as the key to preventing mold, and the World Health Organization's Housing and health guidelines link damp and mold in homes to respiratory illness.

What to do:

• check the natural ventilation draft — a sheet of paper should be drawn toward the grille;
• install an extractor fan with a non-return valve so neighbors' smells don't reach you;
• wire the fan to the light switch with an overrun timer or a humidity sensor;
• leave a gap under the door or fit a transfer grille for supply air.

More on the causes of damp in mold and damp prevention.

Step 4. Plumbing

• Pipe material — polypropylene (PPR) with welded joints or cross-linked polyethylene (PEX) with press fittings. Avoid metal-plastic pipes with threaded joints inside walls.
• Manifold or tee system — a manifold lets you shut off each fixture separately.
• Filters and a pressure reducer at the inlet protect appliances from sand and water hammer.
• Installation frames for a wall-hung toilet and sink save space and make cleaning easier.
• A leak protection system with sensors and automatic valves — cheap insurance against flooding the neighbors.

Photograph all pipework with a tape measure before closing the walls.

Saving Water

The EPA WaterSense program notes that efficient faucets, showerheads and dual-flush toilets significantly reduce water use without sacrificing comfort. Check the flow rate in the fixtures' specifications.

Step 5. Electrics and Safety

A bathroom is a high-risk area for electric shock. The basic rules:

• A residual current device (RCD) with a 30 mA rated residual current on the bathroom circuit — mandatory.
• Zoning — near the bath and shower only equipment with the appropriate ingress protection (IP) rating and, as a rule, low-voltage supply is allowed. Sockets must be at a safe distance from water sources.
• Sockets with covers rated at least IP44.
• Equipotential bonding — metal elements (bath, pipes) are connected to the earthing system.
• Separate circuits for the washing machine and water heater.

More on wiring in apartment electrical wiring. Leave bathroom electrical work to a qualified electrician.

Step 6. Leveling and Waterproofing

1. Level walls with cement plaster or moisture-resistant plasterboard (for boxing-in).
2. Pour a screed sloping to the drain if you're planning a tray-less shower.
3. Apply waterproofing:
   • over the whole floor, turned up the walls by 15–20 cm;
   • in the shower area — the full height of the walls;
   • by the bath — 20–30 cm above the rim;
   • tape all corners and joints with waterproofing tape;
   • fit special collars around pipe outlets.
4. Let the waterproofing dry and test it: flood the floor with water for 24 hours.

Waterproofing is the most important hidden stage. Always photograph the process.

Step 7. Bath or Shower

A bath:

• you can lie down and relax;
• convenient for bathing children;
• takes more space and uses more water.

A walk-in shower (with a floor drain):

• visually enlarges the space;
• barrier-free — convenient for older people;
• requires careful waterproofing and a sloped floor.

A shower cabin with a tray:

• simpler installation;
• fewer demands on the screed;
• less attractive.

Step 8. Tiles

• Format — large-format tiles (60×120 cm and up) make the space look bigger and have fewer joints, but need perfectly flat walls.
• Floor — tiles with an anti-slip surface (R10 and above).
• Grout — epoxy grout is more resistant to moisture and dirt than cement grout.
• Layout — plan it in advance to avoid narrow cuts in visible places.
• Margin — 10–15% for cuts and breakage.

Step 9. Sanitaryware and Furniture

• Faucets — ceramic cartridges last longer; thermostatic faucets keep a stable temperature.
• Toilet — wall-hung or back-to-wall with a rimless bowl for easier cleaning.
• Furniture — moisture-resistant materials; wall-hung vanities make cleaning easier.
• Towel rail — hydronic (from hot water or heating) or electric; in apartments, electric is independent of the season.
• Underfloor heating — electric under tiles adds comfort; size the power correctly and connect via an RCD.

Step 10. Lighting

• General — ceiling lights with moisture protection.
• Task — around the mirror, without shadows on the face.
• Decorative — LED strips in niches and under the vanity.

Ideas for a Small Bathroom

Most bathrooms in typical apartments are 3–4 m². To make them more convenient:

• replace the bath with a shower with a drain and glass screen — the space visually doubles;
• use wall-hung sanitaryware — more floor shows and the room feels bigger;
• hide the cistern and pipes in an installation frame or boxing and add a shelf above;
• choose light large-format tiles and the same material on floor and walls;
• install a mirrored cabinet instead of a plain mirror — extra storage without losing space;
• move the washing machine to the kitchen or a hallway niche if possible;
• choose sliding doors or doors that open outward.

More techniques for small spaces in small apartment design.

How to Accept the Work

Check each stage before it's covered by the next:

• pipework — under pressure (pressure testing), with photos;
• waterproofing — by flooding with water for 24 hours;
• tiles — by tapping (no hollow sounds), even joints, slope to the drain;
• sanitaryware — no leaks during use, hot and cold correctly connected;
• electrics — the RCD works (press "Test"), earthing, protected sockets.

Order of Works

1. Demolition.
2. Riser replacement (agreed with the condominium association).
3. Water and drainage pipework, installation frames.
4. Electrical work.
5. Ventilation.
6. Plaster, boxing-in, screed.
7. Waterproofing with testing.
8. Tiling and grouting.
9. Ceiling.
10. Fitting sanitaryware, furniture, lights and accessories.
11. Sealing joints with sanitary silicone.

Budget

The main cost items:

• rough materials and waterproofing;
• tiles and adhesive;
• sanitaryware and installation frames;
• furniture and mirrors;
• labor;
• a 10–15% contingency.

Large-format tiles, concealed sanitaryware and complex solutions like a walk-in shower have the biggest impact on the budget. Don't skimp on hidden works — waterproofing, pipes and ventilation.

Common Mistakes

• Waterproofing only the shower area instead of the whole floor.
• No access panels for meters and valves.
• Incorrect slope to the drain — water collects in the corners.
• Weak ventilation — mold in the grout within months.
• Sockets in dangerous zones without proper protection.
• No photos of hidden utilities.
• Cheap silicone without antifungal additives around the bath.

Frequently Asked Questions

How long does a bathroom renovation take? Three to six weeks depending on complexity, including drying time for the screed and waterproofing.

Can I lay new tiles over old ones? Technically yes, if the old tiles are firmly attached, but it reduces space and hides possible problems with the substrate.

Paint or tiles? Tiles for areas in contact with water. Outside wet zones, moisture-resistant paint is cheaper and more modern.

Should I replace the risers during renovation? If the risers are old (corroded steel or cast iron), renovation is the best time, since otherwise you'll have to break new tiles later. Risers are common property, so agree the work with the condominium association and the neighbors above and below.

How do I choose a tradesperson? Ask for photos of previous work, including the waterproofing stage, and check reviews. More in how to choose a renovation contractor.

Is underfloor heating worth it in a bathroom? Yes — it dries the floor quickly, reduces damp and makes tiles pleasant underfoot. An electric mat on a timer adds little to the bills if used sensibly.

Conclusion

A good bathroom isn't just beautiful tiles — it's first and foremost proper ventilation, reliable waterproofing, quality pipes and safe electrics. Plan the space, don't skimp on hidden works, photograph everything and follow the sequence — and the bathroom will serve you trouble-free for 15–20 years. More on general planning in our apartment renovation guide.

Sources

• EPA: A brief guide to mold, moisture and your home.
• WHO Housing and health guidelines.
• EPA WaterSense.
• Law of Ukraine on Consumer Rights Protection.
• Civil Code of Ukraine — Chapter 61 "Contract Work".

Read Also

• Mold and damp prevention
• Apartment electrical wiring
• Kitchen renovation: planning and budget
• How to choose a renovation contractor