Bathroom Planning Guide

Bathroom planning fundamentals

Bathrooms are small rooms with a lot of coordination.

The strongest bathroom designs resolve layout, plumbing, drainage, waterproofing, lighting, electrical points, finishes and joinery together. A change to one element often affects several others, so bathroom drawings should be developed as a coordinated package rather than as isolated plans and elevations.

Four things to resolve early

01 · Layout

Movement + privacy

Sanitaryware, circulation, door swings and sightlines need to work before finishes are selected.

02 · Services

Water + drainage

Fixture positions must be compatible with supply, waste, soil stacks and available floor build-up.

03 · Wet zones

Waterproofing

Show where water is expected and coordinate substrates, falls, drains and penetrations.

04 · Details

Edges + junctions

Niches, mirrors, tile cuts, trims, glass, joinery and lighting determine whether the finished room feels resolved.

Quick reference · common coordination points

Element	Coordinate with	Common mistake
Vanity	Basin, mixer, trap, drawers, mirror, lights, sockets	Drawers collide with waste / mirror and lighting are misaligned
Shower	Drain, falls, controls, glass, niche, tile layout	Drain and tile module are decided separately
WC	Cistern frame, wall build-up, flush plate, service access	Concealed frame depth is not allowed for
Bath	Filler, waste, access, structure, cleaning clearance	Freestanding bath is squeezed too close to walls to clean
Lighting	Mirror, vanity, wet zones, ceiling services	Only ceiling downlights are used for facial lighting
Tile	Wall dimensions, niches, sanitaryware, drain, trims	Set-out produces tiny cuts in the most visible locations

Example · Shower wall

Design it as one elevation.

Coordinate the mixer centreline, overhead shower, hand-shower rail, niche, glass edge and tile set-out on the same elevation. If each is located independently, the finished wall can feel misaligned even when every individual product is technically installed correctly.

01 · Start with the bathroom brief

01Confirm who will use the bathroom and whether it is shared, private, guest-facing or accessible.

02Identify daily routines: showering, bathing, grooming, makeup, shaving, storage and laundry.

03Confirm whether the client prefers a bath, shower or both.

04Ask about storage needs, towel storage and countertop clutter.

05Confirm preferred fixture style, finish palette and maintenance expectations.

06Record whether underfloor heating, heated towel rails or smart controls are desired.

07Identify any mobility, child-safety or ageing-in-place requirements.

08Confirm the project budget before specifying premium sanitaryware or stone.

Bathroom planning note

Bathrooms are highly personal. Start with the client's routine, not a catalogue of fixtures.

02 · Survey the existing conditions

01Record room dimensions and ceiling height.

02Locate windows, doors, structural walls and columns.

03Record door swing and clear opening.

04Locate existing hot/cold water supplies.

05Locate visible waste and soil pipe positions.

06Record floor level changes and thresholds.

07Locate ventilation / extract points.

08Photograph service access, risers and existing plumbing zones.

Bathroom planning note

Coordinate this section with the rest of the bathroom package and verify product-specific requirements before issue.

03 · Plan the layout

01Start with sanitaryware positions before decorative finishes.

02Check clear circulation between vanity, WC, bath and shower.

03Avoid door swings colliding with sanitaryware.

04Keep frequently used storage accessible from the vanity.

05Consider privacy sightlines from the bathroom entrance.

06Check whether the WC is visible immediately from adjacent rooms.

07Coordinate towel rails with the actual reach zone from shower or bath.

08Confirm that the proposed layout is compatible with drainage and service constraints.

Bathroom planning note

A beautiful layout that cannot drain correctly is not a viable layout. Check services early.

04 · WC planning

01Allow comfortable clear space around the WC.

02Check centreline and side clearances against local standards and manufacturer requirements.

03Decide between floor-mounted, wall-hung or concealed-cistern systems.

04Provide access to concealed cisterns and service components.

05Coordinate flush plate position with wall finish and joinery.

06Check wall build-up required for concealed frames.

07Position toilet-paper holder within comfortable reach.

08Coordinate bidet spray / hand shower only where appropriate and locally compliant.

Bathroom planning note

Coordinate this section with the rest of the bathroom package and verify product-specific requirements before issue.

05 · Vanity + basin planning

01Choose single or double basin based on room size and client routine.

02Set vanity height to suit the users and basin type.

03Coordinate countertop depth with basin projection.

04Leave usable landing space around the basin.

05Check drawer / cabinet clearance around waste traps.

06Provide storage for everyday toiletries near the basin.

07Coordinate basin mixer reach with basin geometry.

08Dimension mirror, lighting and socket locations from the vanity centreline.

Bathroom planning note

The vanity is where the most daily interactions happen. Storage, lighting, sockets and mirror dimensions should be planned together.

06 · Shower planning

01Confirm shower footprint and door/opening type.

02Check shower-door swing against vanity, WC and circulation.

03Coordinate drain type: point drain, linear drain or tiled channel.

04Set falls toward the drain and coordinate with floor build-up.

05Position shower controls so they are reachable without standing directly under cold water.

06Coordinate overhead shower, hand shower and body spray locations.

07Provide niches or shelves at practical heights.

08Confirm glass panel sizes, fixing method and support.

Bathroom planning note

A shower works best when controls, drain, glass, niche and tile layout are designed as one system rather than separate decisions.

07 · Bath planning

01Confirm freestanding, back-to-wall, inset or built-in bath type.

02Check bath dimensions against user comfort and room proportions.

03Coordinate waste and overflow access.

04Position filler / mixer within reach.

05Check cleaning access around freestanding baths.

06Coordinate floor-mounted fillers with floor build-up and structural requirements.

07Provide nearby towel access.

08Check bath edge / deck requirements for toiletries where relevant.

Bathroom planning note

Coordinate this section with the rest of the bathroom package and verify product-specific requirements before issue.

08 · Waterproofing + wet zones

01Define wet areas before finalising finishes.

02Coordinate waterproofing extent with local regulations and manufacturer systems.

03Detail shower floors, walls, niches and bench seats carefully.

04Coordinate penetrations through waterproofing for mixers, outlets and glass fixings.

05Specify compatible substrates for wet areas.

06Do not rely on decorative tile or grout as the waterproofing layer.

07Ensure floor falls and thresholds are coordinated with the waterproofing system.

08Request specialist confirmation where waterproofing build-up is outside the designer's scope.

Bathroom planning note

Waterproofing is a construction system, not a finish. Decorative tile and grout should never be treated as the waterproofing strategy.

09 · Drainage + floor falls

01Confirm drainage locations before locking the layout.

02Coordinate shower drain location with tile set-out.

03Check that falls can be achieved within the available floor build-up.

04Avoid flat spots around large-format tiles.

05Coordinate linear drain length with shower width.

06Check whether floor level must step down in the shower zone.

07Coordinate waste routes with joists / slabs / structural elements.

08Flag drainage changes for plumber / engineer verification.

Bathroom planning note

Large-format tiles can make falls harder to achieve around point drains. Coordinate tile size and drainage geometry together.

10 · Tile + stone planning

01Choose tile size based on room proportions and floor falls.

02Plan tile set-out from visible focal points rather than hidden corners.

03Minimise awkward slivers at walls and edges.

04Coordinate grout-joint width with tile calibration and manufacturer guidance.

05Align grout lines across floors and walls where appropriate.

06Bookmatch or vein-match stone only when slabs have been reviewed.

07Specify edge trims, mitres and exposed edges.

08Confirm slip suitability for wet floors using locally accepted criteria.

Bathroom planning note

Tile set-out should be intentional. Review the most visible elevations before deciding where cuts begin.

11 · Niches + ledges

01Position shower niches away from direct splash where possible.

02Coordinate niche size with tile module to reduce awkward cuts.

03Set niche height based on products actually stored.

04Allow enough depth for bottles.

05Slope niche shelves slightly toward the shower.

06Coordinate waterproofing before niche framing.

07Check glass / mixer / rail conflicts.

08Dimension niche position on both plan and elevation.

Bathroom planning note

Coordinate this section with the rest of the bathroom package and verify product-specific requirements before issue.

12 · Mirrors + lighting

01Coordinate mirror size with vanity width.

02Provide facial lighting from the front / sides rather than relying only on overhead downlights.

03Set wall-light positions based on user height and mirror dimensions.

04Check integrated mirror lighting colour temperature and CRI.

05Coordinate demister pads and power requirements where used.

06Keep decorative lights clear of wet zones unless appropriately rated.

07Coordinate mirror edges with wall finishes and sockets.

08Verify local electrical requirements for all fittings in wet areas.

Bathroom planning note

Mirror lighting is primarily about faces, not ceilings. Overhead light alone often creates harsh shadows.

13 · Electrical + sockets

01Locate sockets based on actual appliance use: hairdryer, shaver, toothbrush, styling tools.

02Keep sockets outside restricted wet zones as required locally.

03Coordinate socket heights with vanity and mirror.

04Provide power for illuminated mirrors, demisters and smart WCs where needed.

05Coordinate heated towel rail supplies.

06Coordinate underfloor heating controls.

07Provide service access for drivers / transformers.

08Have all zone, circuit and protection requirements verified by the electrical professional.

Bathroom planning note

Electrical rules in bathrooms vary by jurisdiction. Use the relevant local code and qualified electrical professional rather than copying generic wet-zone diagrams.

14 · Ventilation + humidity

01Confirm whether natural ventilation is sufficient under local requirements.

02Provide mechanical extract where required.

03Position extract points to remove moisture effectively.

04Coordinate grilles with the reflected ceiling plan.

05Check duct route and external termination.

06Coordinate fan switching / humidity sensor strategy.

07Ensure joinery materials are suitable for humid environments.

08Consider mirror demisting and condensation-prone surfaces.

Bathroom planning note

Good ventilation protects finishes, joinery, mirrors and indoor air quality. It should be resolved during design, not after condensation appears.

15 · Heating + comfort

01Confirm whether underfloor heating is required.

02Coordinate heated towel rail size with actual towel capacity.

03Position towel rails where towels can dry properly.

04Avoid overheating tiny bathrooms with oversized emitters.

05Check controls and thermostats are accessible.

06Coordinate heating with joinery and sanitaryware.

07Confirm floor finish compatibility with underfloor heating.

08Allow for seasonal comfort, not only visual design.

Bathroom planning note

Coordinate this section with the rest of the bathroom package and verify product-specific requirements before issue.

16 · Storage + joinery

01Store daily items within easy reach of the vanity.

02Separate open display from concealed storage.

03Check drawer depth against traps and plumbing.

04Use moisture-resistant materials and suitable edge treatments.

05Provide ventilation where joinery encloses electrical / mechanical equipment.

06Coordinate medicine / mirror cabinets with wall depth.

07Check handle and door clearances.

08Detail shadow gaps, plinths and wall junctions for easy cleaning.

Bathroom planning note

Coordinate this section with the rest of the bathroom package and verify product-specific requirements before issue.

17 · Accessibility + safety

01Check local accessibility requirements where the project requires an accessible bathroom.

02Provide adequate circulation / transfer space where needed.

03Use slip-resistant floor finishes appropriate to the space.

04Consider grab-bar backing even if bars are not installed immediately.

05Reduce trip hazards at thresholds.

06Use thermostatic mixing / anti-scald measures where appropriate.

07Provide reachable controls and storage.

08Coordinate door width, swing and emergency access requirements.

Bathroom planning note

Accessible design requirements can be highly specific. Where accessibility is part of the brief, verify the applicable local standard before issue.

18 · Drawing package checklist

01General arrangement plan shows all sanitaryware and clearances.

02Dimension plan includes critical setting-out dimensions.

03Floor finish plan shows tile / stone layout and thresholds.

04Reflected ceiling plan coordinates lighting, extract and access panels.

05Electrical plan shows sockets, switches, mirror power and heating controls.

06Plumbing plan shows fixture locations and required connection points.

07Wall elevations cover every critical wall.

08Joinery details show vanity construction and service access.

09Shower / bath details show niches, drains, glass and fittings.

10Specification codes match the drawings.

Bathroom planning note

Coordinate this section with the rest of the bathroom package and verify product-specific requirements before issue.

19 · Specification checklist

01Sanitaryware manufacturer / model.

02Tapware manufacturer / model / finish.

03Basin / bath / WC dimensions.

04Shower system components.

05Tile / stone manufacturer, finish and size.

06Grout colour and joint width.

07Waterproofing system where within scope.

08Glass type / finish / hardware.

09Mirror type and dimensions.

10Lighting references.

11Joinery finish and hardware.

12Accessories and towel rails.

13Lead times and supplier information.

Bathroom planning note

Coordinate this section with the rest of the bathroom package and verify product-specific requirements before issue.

20 · Pre-issue QA

01All fixture dimensions are based on current manufacturer data.

02Door and shower-screen swings have been checked.

03Drainage and plumbing changes are flagged for verification.

04Tile set-out matches elevations.

05Niches align with tile layout.

06Mirror, lighting and sockets are coordinated.

07Vanity drawers do not clash with plumbing.

08Shower controls and hand shower are ergonomically located.

09Waterproofing and thresholds are clearly resolved.

10Ventilation is accounted for.

11Wet-area electrical requirements have been verified.

12Every drawing and specification uses the same fixture codes.

Bathroom planning note

Before issue, review the bathroom in plan, elevation and section at the same time. Most mistakes are coordination mistakes between these drawings.

Bathroom Planning Guide