1.1 Throughput × Hygiene × Serviceability

A useful working formula is: Throughput × Hygiene × Serviceability. A design that excels in one dimension but fails in another underperforms over the facility life.

• Model peak demand (event breaks, shift changes, intermissions).
• Reduce touchpoints via sensor-activated handwashing and flushing.
• Prioritize accessible chases, standardized parts, and safe clearances.

1.2 Intuitive, Predictable User Flow

• Align wash–soap–dry in a single, logical sequence.
• Provide clear sightlines from entry to handwashing and circulation zones.
• Use lighting and finishes to visually cue entry, queuing, and fixture zones.

1.3 Low-Touch Hygiene by Default

• Specify IR or capacitive-sensor faucets, soap, and flush valves (150–300 ms).
• Use thermostatic mixing valves (ASSE 1070) for comfort and anti-scald protection.
• Design for easy cleaning: clearance around fixtures, sealed penetrations, fewer dirt traps.

1.4 Maintainability & Life-Cycle Cost

• Locate isolation valves and filters where they can be serviced quickly.
• Standardize SKUs for flush valves, sensors, and spouts across floors.
• Provide digital O&M access (QR codes on access panels linked to SOPs).

2.1 Traditional Gendered Core

• Separate male/female rooms flanking a core service chase.
• Efficient for repetitive floor plates (offices, hospitality, education).
• Verify fixture counts against local plumbing codes and allow future-ready rough-ins.

2.2 All-Gender Compartmentalized

• Fully enclosed WC rooms with shared handwashing zone.
• Supports inclusive design and reduces queuing imbalance.
• Coordinate exhaust per compartment and maintain negative pressure at the shared zone.

2.3 High-Throughput Concourse / Arena

• Long banks of fixtures with multiple entry and exit points.
• Prioritize wide circulation aisles and robust floor drainage.
• Model queuing to avoid back-flow into concourses during peak intervals.

2.4 Family, Assisted & Care Settings

• Provide dedicated rooms for caregivers, children, and mobility devices.
• Include robust grab-bar layouts and change benches where warranted.
• Coordinate hardware, door swings, and auto openers for smooth transfers.

4.1 Lavatories & Handwashing

• Specify IR faucets tuned for ≈ 0.3 s actuation and hard shut-off.
• Target ≤ 0.35 GPM at design pressure, verified during commissioning.
• Use basin geometries tested for low splash and adequate throw.
• Consider integrated soap, water, and dry-at-basin solutions.

4.2 Toilets, Urinals & Flush Valves

• Pair fixtures with matching flush valves for proven performance.
• Favor WaterSense-labeled fixtures where applicable.
• Provide hands-free actuators in high-use and healthcare settings.
• Coordinate access panels, isolation valves, and vacuum breakers.

4.3 Metering & Data

• Sub-meter restroom water usage by zone or floor.
• Integrate leak detection and runtime alerts with the BMS.
• Provide simple dashboards or reports for operations teams.

4.4 Thermal Comfort & Energy

• Use thermostatic mixing valves sized and located for access.
• Insulate hot water piping and minimize dead legs.
• Consider drainline or graywater heat recovery in large facilities.

5.1 Beyond Minimum ADA

• Consider powered doors in larger developments.
• Use visual contrast at floor–wall–fixture interfaces.
• Provide multiple grab bar configurations for sit-to-stand assistance.

5.2 All-Gender & Privacy

• Use full-height partitions with minimal floor and ceiling gaps.
• Place handwashing zones in sight of circulation but away from direct entry views.
• Provide clear, inclusive wayfinding and signage.

5.3 Caregiver & Family Needs

• Integrate baby changing, family rooms, and adult changing facilities where needed.
• Allow maneuvering clearance for prams, mobility aids, and service animals.
• Coordinate alarms and call buttons with life safety plans.

6.1 Ventilation Strategy

• Size exhaust per ASHRAE 62.1 and local code.
• Maintain negative pressure relative to adjacent spaces.
• Avoid locating supply diffusers directly over stalls or handwashing.

6.2 Moisture & Mold Prevention

• Use continuous or demand-controlled exhaust in high-load facilities.
• Provide robust floor drainage and sloped surfaces at entries and basins.
• Detail transitions at wet walls, backsplashes, and penetrations carefully.

6.3 Acoustic Comfort

• Use sound-absorbing ceilings and selective wall treatments.
• Detail partitions to reduce sound transmission between stalls.
• Coordinate background noise levels for privacy and comfort.

7.1 Floors & Slips

• Target slip resistance in line with ANSI A326.3 in wet zones.
• Minimize grout joints; favor large-format tiles or poured systems.
• Carry floor finishes into stalls with continuous slope to drains.

7.2 Walls, Partitions & Ceilings

• Use moisture-resistant boards and coatings at wet walls.
• Select durable, cleanable partition surfaces with concealed hardware.
• Coordinate ceiling systems for access to dampers, piping, and electrical.

7.3 Fixtures, Accessories & Fittings

• Minimize exposed fasteners and dirt traps around accessories.
• Standardize finishes (e.g., brushed stainless) across fixtures.
• Provide task lighting at mirrors, vanities, and cleaning zones.

8.1 Access & Service Clearances

• Provide rear or side service corridors for high fixture densities.
• Keep key valves, filters, and sensors within ergonomic reach.
• Allow space for carts, floor machines and temporary barriers.

8.2 Telemetry & Smart Features

• Integrate data only where the operators have a plan to use it.
• Prioritize actionable alerts – leaks, low supplies, outages.
• Address cybersecurity and network segmentation with IT.

8.3 Cleaning Workflows

• Design “clean from dry to wet” routes in order to minimize cross-contamination.
• Include storage for supplies near each restroom bank.
• Review fixture heights and spacing with custodial teams.

9.1 Pre-Functional Checks

• Verify rough-in heights, clearances, and blocking against details.
• Confirm fixture models match approved submittals and data.
• Check slopes to drains, door swings, and partition alignment early.

9.2 Functional Performance Testing

• Measure flow rates, sensor response times, and flush performance.
• Smoke test or visualize airflows to confirm negative pressure.
• Log water meter and sub-meter baselines for benchmarking.

9.3 Training, Manuals & Optimization

• Deliver hands-on training for operations and custodial staff.
• Provide digital O&M linked to QR codes and asset IDs.
• Plan a 6–12 month post-occupancy review to tune settings.

Accessibility & Inclusive Design

• 2010 ADA Standards for Accessible Design
• Local building and accessibility codes (IBC and regional variants).

Water Efficiency & Plumbing Performance

• EPA WaterSense Program
• LEED v4.1 — Water Efficiency

Indoor Environmental Quality & Health

• ASHRAE 62.1 — Ventilation for Acceptable IAQ
• WELL Building Standard