7 Things Your Bathroom Plans Must Include (Before You Build)

Written By Mia Blanford

Bathroom renovations don’t go wrong because of tiles or tap ware.
They go wrong because the plans don’t go far enough.

Missing details lead to on-site decisions.
On-site decisions lead to changes.
And that’s where costs start creeping up.

If you’re planning a bathroom renovation, these are the things your drawings need to show — clearly — before construction begins.

1. A Fully Dimensioned Floor Plan

Not just a layout — actual dimensions.

Wall-to-wall measurements, fixture locations, clearances.
Everything needs to be set out so the builder knows exactly where things go.

If it’s vague, it gets guessed.

2. Internal Elevations (Every Wall)

This is where most people fall short.

Each wall should be drawn out showing:

  • Tile extents

  • Vanity position

  • Mirror and lighting

  • Tapware locations

Without elevations, the builder is left to interpret the design.

3. Set-Out for Plumbing Fixtures

Toilet. Vanity. Shower. Bath.

Exact locations and heights need to be documented — not approximated.

Because once plumbing is in, changing it is expensive.

4. Tile Layout + Finishes

Not just “600x600 tiles”.

Plans should show:

  • Where tiles start and stop

  • Feature tiles or niches

  • Floor vs wall transitions

  • Grout considerations (if relevant)

This is what controls how the bathroom actually looks.

5. Lighting + Electrical Plan

Where are the lights?
What type are they?
Where are switches and power points?

Think:

  • Vanity lighting

  • Ceiling lights

  • Exhaust fan

  • GPOs

If this isn’t resolved early, it becomes a last-minute decision.

6. Joinery + Vanity Details

Your vanity isn’t just a box.

Plans should show:

  • Width, depth, height

  • Drawer vs door configuration

  • Basin type and position

  • Storage allowance

This is where function meets design.

7. Waterproofing + Falls (Design Intent)

Even if the builder handles compliance,
your drawings should still show intent.

  • Shower area

  • Screen position

  • Floor falls direction

  • Drain location

Because these decisions affect both performance and appearance.

Why This Matters

A bathroom is one of the most detailed spaces in your home.

If it’s not resolved properly on paper,
it will get resolved on site — under pressure.

And that’s when mistakes happen.

If you’re planning a bathroom renovation

Before choosing tiles or fittings,
make sure your plans actually cover what they need to.

If you’re not sure where your drawings sit,
I’m always happy to take a look.

Mia Blanford
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