A lot of bathroom projects go wrong before the first tile is lifted.

Not because the suite was wrong, or the tiles were ugly, or the fitter was bad. Usually it is because the decisions were made in the wrong order.

This guide is built around the real search intent behind bathroom renovation queries: what should I decide first, what matters most, and what mistakes are easiest to avoid?

What should you decide before a bathroom renovation?

If you want the shortest version, decide these first:

1. Who uses the bathroom and how

2. Whether it is bath, shower, or both

3. Where the waste runs and plumbing need to go

4. How the room will be ventilated

5. What flooring is safe and practical

6. What lighting and electrics you need before the walls are closed

That order matters because ventilation, drainage, hot water safety and electrical work all sit inside recognised Building Regulations guidance, not just the decorative part of the job. Approved Document G covers bathrooms, hot water safety and water efficiency, Approved Document F covers ventilation, Approved Document H covers drainage and waste disposal, and Approved Document P covers electrical safety in dwellings.

If you want the installation side handled professionally, the most relevant internal page is Kitchen & Bathroom Installations.

What should you plan before choosing tiles and taps?

This is the bit people rush.

Before you choose finishes, decide:

• whether this is a family bathroom, ensuite, cloakroom or guest room

• whether you need daily practicality or more of a spa feel

• how much storage you actually need

• whether the room needs to feel bigger, brighter, warmer, or easier to clean

Once that is clear, the layout becomes much easier. If you pick the tiles first, then try to force the room around them, you usually end up compromising on storage, extraction or movement space.

A simple rule that helps: plan the function first, then the fixed positions, then the finishes.

Should you choose a bath, a shower, or both?

That decision shapes almost everything else.

Choose a shower-first layout if:

• this is the main everyday bathroom

• speed and ease matter most

• the room is small and you need better circulation

• you want simpler cleaning

Keep a bath if:

• you have young children

• it is your only bathroom and you want flexibility

• you know the household actually uses one regularly

This sounds obvious, but it saves a lot of regret. Too many bathroom renovations are designed for a fantasy version of the home, not the way the room is really used.

What plumbing and drainage checks should you do before work starts?

This is one of the easiest ways to avoid nasty surprises mid-project.

Before committing to a new layout, check:

• whether the current waste runs suit the new positions

• whether the existing drainage is already slow

• whether water pressure is strong enough for the shower setup you want

• whether there are signs of previous leaks under basins, baths or trays

Drainage and waste disposal are covered by Approved Document H, which is one reason layout changes should be thought through early rather than after strip-out.

If the room already has signs of slow drainage, smells or repeat blockages, sort that first. Checkout this related article for that: Blocked Drains and Leaks: Weekly Routine + Never Pour List.

How important is ventilation in a bathroom renovation?

It is one of the most important decisions in the room.

A bathroom that looks great on day one can still become a condensation problem if the extraction is weak, badly ducted or treated like an afterthought. Approved Document F sets out the ventilation requirements for dwellings, and wet rooms like bathrooms are exactly where extract ventilation matters most.

So before choosing mirrors, wall colours or fancy fittings, ask:

• where will the extractor go?

• is it venting properly to the outside?

• will it actually clear steam after showers?

• is there enough background airflow to stop moisture hanging around?

If this is already a condensation-prone room, pair this article with Ventilation Upgrades That Reduce Condensation.

What flooring works best in a bathroom?

The practical answer is usually porcelain tile or a bathroom-suitable resilient floor such as LVT, depending on the look and the installation plan.

Porcelain is still a strong option because it is hard-wearing and has very low water absorbency. The Tile Association also highlights slip resistance as a key consideration, especially in wet areas such as shower spaces and bathrooms.

That means the right bathroom floor is not just about colour or pattern. It is about:

• slip resistance

• moisture suitability

• cleaning

• how it feels underfoot

• whether it fits the rest of the house

If you want the broader room-by-room flooring piece for internal linking, use Flooring Trends for 2026: Family-Proof LVT, Herringbone Looks and Tile Choices That Don’t Date.

What electrical and lighting decisions should you make early?

Bathroom lighting should not be a last-minute add-on.

Before work starts, decide:

• whether you want task lighting at the mirror

• whether you need better general ceiling lighting

• whether storage lighting or feature lighting actually helps the room

• whether the extractor and lighting controls should work together

Electrical safety in dwellings is covered by Approved Document P, and the current edition explains when notification of work is required.

That does not mean the article needs to become a technical lecture. It just means the electrical plan belongs in the early design stage, not after tiles are chosen.

What mistakes cause the most bathroom renovation regret?

1. Choosing finishes before layout

This is still the biggest one. Nice tiles do not rescue a poor layout.

2. Ignoring ventilation

If the room traps moisture, the bathroom will feel older faster, no matter how new it looks. Approved Document F exists for a reason.

3. Forgetting storage

A bathroom without enough storage looks cluttered quickly.

4. Picking the wrong floor for the room

A good-looking floor that is awkward to clean or too slippery in wet use is not a smart choice. The Tile Association specifically advises considering slip resistance according to intended use.

5. Starting without checking drainage and existing issues

If the room already has slow waste, hidden leaks or recurring damp, the renovation should solve that, not cover it.

Bathroom renovation checklist

Use this as the working checklist before anything is ordered.

First decisions

• Who uses this bathroom every day?

• Bath, shower, or both?

• Do we need more storage than we have now?

• What really annoys us about the current room?

Practical checks

• Is the drainage already slow or problematic?

• Are there any signs of old leaks?

• Is the current extractor good enough?

• Does the layout need major plumbing moves?

Finish decisions

• What floor is safest and easiest to live with?

• What wall finish suits the moisture level in the room?

• What lighting do we need at the mirror and ceiling?

• Are we choosing things that will still feel right in a few years?

FAQs

What should I choose first in a bathroom renovation?

Start with layout and function, not finishes. Then make the plumbing, ventilation, flooring and lighting decisions before picking the decorative details.

Do bathrooms need special ventilation?

Bathrooms need effective ventilation because they are a major source of indoor moisture. Approved Document F sets out ventilation guidance for dwellings, including wet rooms such as bathrooms.

Is tile always the best bathroom flooring?

Not always, but it is often the safest traditional answer. Porcelain tile is especially popular because it is hard-wearing and low in water absorbency, while slip resistance should be considered based on the wet use of the space.

Do bathroom electrics need special consideration?

Yes. Electrical safety in dwellings is covered by Approved Document P, which is why lighting and electrical choices should be planned properly from the start.