Hot Water Heater Bypass Valve — A Small Upgrade With Big Benefits

One of the smartest additions you can make to any RV or cargo‑conversion plumbing system is a
hot water heater bypass valve. I recently watched a great walkthrough on how these valves work,
and it reinforced why this little setup is worth including in any build—especially one designed
for year‑round use.

What a Bypass Valve Does

A bypass valve gives you full control over whether water flows into the hot water heater or
around it. That flexibility matters for two major reasons:

1. Winterization Made Easy

When it’s time to winterize, you don’t want gallons of antifreeze filling your hot water tank.
A bypass valve lets you isolate the heater so antifreeze only travels through the lines—not the tank—
saving time, money, and cleanup.

2. System Flexibility & Maintenance

If you ever need to service, replace, or temporarily disable your water heater, the bypass lets you
keep the rest of your plumbing system fully operational. Cold water continues flowing to your fixtures
while the heater stays offline.

How It Works

A typical bypass setup uses two shutoff valves and a short crossover line:

Valve A: Stops cold water from entering the heater
Valve B: Stops hot water from exiting the heater
Crossover Line: Connects cold to hot so the system stays pressurized and functional

Turn two valves, and the entire heater is isolated. Simple, clean, and reliable.

Why I’m Including It in My Build

My plumbing system is designed for serviceability and future upgrades, and the bypass valve fits
perfectly into that philosophy. It supports:

Easy winterization
Quick maintenance
Future heater swaps (gas or electric)
Cleaner plumbing architecture

It’s a small detail that pays off every single year.

80/20 IdeaBuilder – Design Tool for Extruded Aluminum Framing

As I plan to use extruded aluminum (T-slot) for parts of my cargo trailer conversion,
80/20’s IdeaBuilder is the main design tool I’ll use to lay out and visualize the framing.
This page is a reference for how I’m using IdeaBuilder in the design process and why it fits well with my modular, serviceable build approach.

What IdeaBuilder Is

IdeaBuilder is an online design tool from 80/20 that lets you quickly create frames and structures using their T-slot profiles.
It provides:

Drag-and-drop design: Build frames visually using standard 80/20 profiles.
Automatic Bill of Materials (BOM): Generates part numbers, lengths, and quantities.
Multi-view drawings: Front, top, side, and isometric views for reference.
Exploded views: Shows how each piece fits into the assembly.

I’ve already used it to create a base frame design that’s close to what I want for the kitchen cabinet structure.

How I Plan to Use IdeaBuilder

I will use IdeaBuilder as a framing design sandbox for:

Kitchen base frame: Designing the aluminum structure that supports the butcher block countertop and sink.
Mechanical/electrical bays: Frames for mounting power equipment, tanks, and other systems.
Modular structures: Any area where I want the ability to reconfigure or upgrade later.

Once I’m happy with a design in IdeaBuilder, I can export or reference the BOM and then source equivalent profiles from suppliers like TNutz.

Benefits for the Trailer Build

Accurate dimensions: Helps ensure the aluminum frames match the real-world space inside the trailer.
Pre-planned cuts: The BOM gives exact lengths, which I can translate into cut plans for 96″ sticks.
Visual clarity: Multi-view and exploded views make it easier to see how everything ties together.
Iterative design: I can adjust spans, add supports, or create openings (like for a sink) before committing to material.

Notes for Future Reference

Use IdeaBuilder to finalize the kitchen base frame before ordering extrusions.
Document which 80/20 profiles in the design correspond to TNutz or other supplier equivalents.
Save PDFs of BOMs and drawings for each major frame (kitchen, mechanical bay, etc.).
Update this page as I refine designs and lock in final frame dimensions.

This page serves as a reminder that IdeaBuilder is my primary design environment for any extruded aluminum framing used in the cargo trailer conversion.

TNutz

TNutz – Reference Supplier for Extruded Aluminum

As I plan different parts of the cargo trailer conversion, I am strongly considering using
extruded aluminum (T-slot) for structural frames, bases, and modular components.
If I go that route, TNutz is one of the primary suppliers I will use for profiles, hardware, and accessories.
This page is a reference point for their products, pricing style, and how they might fit into my build.

Why TNutz Is on My Short List

Affordable profiles: Their 1″ x 1″ (1010) and other common sizes are priced competitively, especially in longer lengths like 96″.
Cut-to-length options: They offer both full sticks and cut services, which is useful for minimizing waste.
Compatible hardware: Brackets, corner connectors, anchor fasteners, and T-nuts are all available in one place.
DIY-friendly: Their catalog is straightforward and well-suited for custom projects like trailer conversions, workbenches, and modular furniture.

How I Plan to Use TNutz in the Build

If I move forward with extruded aluminum, TNutz will likely be used for:

Kitchen base frames: 1010 or similar profiles for the lower cabinet structure under the butcher block countertop.
Modular support frames: For mechanical bays, electrical enclosures, or removable panels.
Mounting structures: Frames for equipment like power stations, tanks, or HVAC components where adjustability is helpful.

The ability to bolt, adjust, and reconfigure components over time fits well with the long-term, serviceable design I’m aiming for.

Example Profile Reference

One of the main profiles I’ve looked at from TNutz is:

Profile: 1″ x 1″ T-slot extrusion (1010 equivalent)
Length: 96″ sticks
Use Case: Vertical legs, horizontal rails, and cross-members for the kitchen base and other frames.

I will use this page to keep track of which profiles and lengths I’ve evaluated, along with any cost estimates I generate for specific sub-projects.

Notes for Future Reference

Confirm final profile sizes (1010 vs 1020, etc.) based on load and span requirements.
Standardize on a small set of connectors and fasteners to simplify assembly and spare parts.
Document cut plans for each project (kitchen base, mechanical bay, etc.) to optimize use of 96″ sticks.
Compare TNutz pricing and availability with other suppliers only if project scope grows significantly.

This page will be updated as I refine which parts of the build will use extruded aluminum and which specific TNutz components I decide to standardize on.

Tank vs. Tankless RV Water Heaters

Tank vs. Tankless RV Water Heaters for a Cargo Trailer Conversion

Plumbing
Systems Planning
Hot Water

As I plan the plumbing and hot water strategy for my cargo trailer conversion, I’ve been digging into the
real-world differences between traditional tank-style RV water heaters and
tankless/on-demand units. A recent video, “Tank Vs Tankless RV Water Heaters”,
pulled together a lot of practical experience from RV owners, and this post captures the key points
and how they apply to my build.

1. Hot Water Delivery and User Experience

Tank-style heaters store and pre-heat a fixed volume of water, so hot water is available
almost immediately at the faucet. You open the tap, and you’re essentially drawing from a pre-heated reservoir.

Tankless heaters work differently: they need a minimum flow to trigger the burner, then ramp up
to temperature. That means a delay before hot water arrives, and some variability as the system stabilizes.
Certain premium models (like the Truma AquaGo) offer a “comfort” or recirculation mode to keep water warm
in the lines, but that comes with additional energy use.

2. Water Usage and Conservation

One of the big tradeoffs with tankless systems is water waste during warm-up. Until the heater
reaches the target temperature and pushes that hot water all the way to the fixture, you’re sending usable water
down the drain. For anyone with limited gray tank capacity, that’s not trivial.

With a tank heater, the water is already hot and more predictable, so it’s easier to mix hot and
cold at the faucet and get to a comfortable temperature quickly. That can translate into less fiddling and less
waste overall.

3. Fuel, Power, and Flexibility

A common selling point for tankless heaters is efficiency: they only fire when water is flowing.
Many RV owners report lower propane usage after switching to tankless, especially if they take longer showers.

Tank heaters, on the other hand, often support multiple modes—propane, electric, or both.
That flexibility matters at campgrounds where shore power is available: you can save propane by running on
electric, or use both for faster recovery when demand is high.

4. Winter Performance and Cold-Weather Behavior

Cold weather exposes some of the weaknesses of tankless systems. They can be more sensitive to:

Low incoming water temperatures
Low water pressure or marginal pumps
Temperature rise limits across the heat exchanger

Owners in colder climates sometimes add insulation, small heaters, or circulation loops to keep lines from
freezing and to stabilize performance. By contrast, tank heaters tend to be more predictable
in winter, as the entire tank is kept at temperature and the system is generally simpler.

5. Installation, Tuning, and Reliability

Tankless units are more “tunable” but also more finicky. They care about:

Water pressure: too low and they may not fire consistently.
Flow rate: fixtures with very low-flow aerators can cause cycling.
Temperature rise: large jumps from cold inlet to hot outlet push the unit harder.

Tank heaters are mechanically simpler and often more forgiving. While both types can be reliable
when installed correctly, the tank-style design has fewer variables to tune and fewer edge cases to manage.

6. Real-World Experiences from RV Owners

The comments and user experiences around this topic are split, but informative:

Pro-tankless: Full-timers love the “endless shower” experience and reduced propane usage.
Back-to-tank: Some owners reverted to tank heaters after frustration with cold-weather
performance or water waste.
Hybrid setups: Others run creative combinations—small under-sink electric heaters,
recirculation loops, or dual-mode tank heaters—to get the best of both worlds.

How This Informs My Trailer Build

For my cargo trailer conversion, the decision isn’t just “tank vs. tankless”—it’s about how the entire
hot water system interacts with gray tank capacity, winter use, and
fixture layout.

Endless hot water is appealing, but the delay and extra water down the drain are real
concerns with a finite gray tank.
Cold-weather reliability matters, especially if the trailer sees shoulder-season or
winter trips.
A hybrid approach—for example, a traditional tank heater combined with a small
point-of-use electric heater near the shower or sink—could minimize wait time and water waste.
Heater placement relative to fixtures will be critical. Shorter runs mean less delay,
less wasted water, and a better overall experience regardless of heater type.

I’m leaning toward a solution that prioritizes predictability, water conservation, and serviceability,
even if that means giving up the “infinite” hot water promise of a pure tankless setup.

Waste Water Drain Tips

Cargo Trailer Conversion – Waste Water Drain Tips (Reference)

This page documents helpful waste‑water plumbing tips from the video
“Cargo Trailer Conversion Waste Water Drain Tips. Uniseal. Waste Water Tanks. RV Sewer Adapters.”
by I Ride Tiny House Adventures. I’m saving these notes as a reference for my own plumbing system design.

1. Using Uniseals for Tank Penetrations

The video highlights how effective Uniseals are for creating watertight penetrations in plastic waste tanks.
They allow pipes to pass through the tank wall without needing threaded bulkheads, and they flex with tank movement.

Key points:

Use a —cheap ones can cut oversized holes and cause leaks.
Lubricate the pipe and seal to avoid tearing the rubber during installation.
Uniseals work well for both grey and black water tanks.

2. Preventing Leaks at Fittings

One commenter recommended applying a small amount of grease on the gasket before tightening fittings.
This helps the gasket compress smoothly instead of dragging and tearing.

This is especially useful when installing:

Threaded adapters
Tank outlet fittings
RV sewer connectors

3. RV Sewer Adapters & Drain Options

The video shows how to adapt from smaller drain lines (1.5″) up to standard RV sewer sizes (3″).
This is helpful when combining shower, sink, or sump‑pump outputs into a larger drain system.

Tips mentioned:

Offset fittings can help align pipes when tank ports aren’t perfectly positioned.
Some builders downsize to a garden hose adapter for slow but simple grey‑water draining.
Always use high‑quality PVC fittings to avoid cracking under vibration.

4. Waste Tank Selection & Installation Notes

Viewers in the comments mentioned using 36–55 gallon tanks and pairing them with shower sump pumps for interior plumbing.
This aligns with my own plan to keep all tanks inside the trailer for freeze protection.

General reminders:

Verify tank wall thickness before choosing Uniseal sizes.
Support tanks fully—don’t rely on fittings to carry weight.
Plan drain locations early to avoid conflicts with framing.

5. Safety & Practical Tips

Use flush‑cut zip‑tie cutters to avoid sharp edges that can cut your hands.
Keep spare fittings and caps for emergency repairs.
Label drain lines during installation for easier troubleshooting later.

Why This Video Is Useful for My Build

This video provides practical, real‑world examples of how to handle waste‑water plumbing in a cargo trailer conversion.
The tips on Uniseals, gasket sealing, and sewer adapters will directly influence how I design my grey‑water system, sump‑pump connections, and tank penetrations.

This page will serve as an ongoing reference as I finalize my plumbing layout.

Reference: EcoFlow Delta Pro Transfer Switch Installation for Boondocking

This post documents key takeaways from the video
“Best EcoFlow Delta Pro Setup for Boondocking – Install a Transfer Switch!”.
The creator demonstrates how to integrate an EcoFlow Delta Pro into an RV electrical system using an
automatic transfer switch (ATS), allowing the power station to safely power all onboard circuits while remaining protected inside a storage compartment.

This installation method is relevant to my electrical planning, especially as I evaluate the EcoFlow DELTA Pro 3, the Smart Generator 4000, and a 50‑amp shore power inlet for the cargo trailer conversion.

Overview of the Setup

The video shows how the installer wires an ATS into the RV’s existing shore‑power line so the EcoFlow Delta Pro can power the entire RV without running an external cord. The Delta Pro remains inside a storage compartment, protected from weather and theft. The ATS automatically switches between:

Shore power
EcoFlow Delta Pro
Generator input

This allows all interior outlets and circuits to remain live regardless of the power source. The EcoFlow can also recharge from shore power through the same wiring path.

Key Details from the Installation

Shore power line is cut and routed into the transfer switch, then back out to the RV’s breaker panel.
EcoFlow Delta Pro output is connected to the second input of the ATS.
Generator plug is connected to the third input.
The Delta Pro remains inside a storage compartment, protected from weather and theft.
The system allows the RV to recharge the Delta Pro from shore power without moving the unit.

Safety Considerations Mentioned

Several comments and responses highlight important safety notes:

Ventilation: The storage compartment in the video has ~15 sq in of airflow, preventing overheating. The Delta Pro’s BMS will throttle or shut down if temperatures rise too high.
Aluminum-to-copper wiring: When joining dissimilar metals, an anti‑oxidant compound should be used to prevent oxidation and fire risk.
Breaker management: Some RVs require turning off the onboard battery charger to avoid unnecessary load on the power station.

Why This Setup Is Useful for My Build

This installation method aligns well with my electrical system goals:

Keep the EcoFlow unit inside the trailer for protection.
Use a transfer switch to safely manage shore, generator, and battery power.
Allow the EcoFlow to power all circuits without external cords.
Enable automatic charging from shore power.
Maintain a clean, modular, serviceable electrical system.

This video serves as a practical reference for integrating the EcoFlow ecosystem into the cargo trailer conversion, especially as I evaluate the DELTA Pro 3, the Smart Generator 4000, and a 50‑amp shore power inlet.

Notes for Future Planning

Determine ATS size and compatibility for a 50‑amp shore power inlet.
Evaluate ventilation requirements for the EcoFlow storage compartment.

Save a Drop P3 Water Flow Meter – Fresh Water Fill Monitoring

As part of planning the fresh water system for this cargo trailer conversion, I wanted a simple way to
monitor how much water is going into the tanks during fills.
A small inline flow meter on the hose is an easy, low‑tech way to track gallons used and avoid overfilling.

One product I’m considering for this purpose is:

Save a Drop P3 Blue Water Flow Meter – Measure Gallon Usage from an Outdoor Garden Hose

Product Overview

The Save a Drop P3 is a compact, inline water flow meter that attaches to a standard garden hose.
It measures the total volume of water passing through and displays usage in gallons, making it useful for
filling RV or trailer fresh water tanks, portable containers, or even just tracking water consumption.

Type: Inline water flow meter
Connection: Standard garden hose
Display: Digital readout of gallons used
Use Case: Monitoring tank fills and conserving water

Why This Is Useful for the Build

When filling fresh water tanks, it’s easy to lose track of how much water has gone in—especially when filling from
portable containers or non‑metered sources.
A small flow meter like this provides:

Overfill awareness: Know how many gallons have gone into the tank before it reaches capacity.
Repeatable fills: Easy to track partial fills (e.g., “add 10 gallons” instead of “fill until it overflows”).
Water usage insight: Helps understand how quickly water is consumed during trips.
Portable and flexible: Can be used on any hose, not permanently installed.

How It Fits Into the Fresh Water Workflow

In practice, this meter would be attached inline on the hose used to fill the fresh water tank(s).
Before starting a fill, the meter can be reset to zero, and the display will show the total gallons added during that session.

Attach meter between spigot and hose, or hose and tank fill.
Reset meter before each fill.
Monitor gallons as the tank fills to avoid overfilling.
Optionally log usage to better understand daily water consumption.

This page serves as a reference for a simple, portable tool that can make tank filling more controlled and predictable,
especially when working with multiple tanks or off‑grid water sources.

Bathroom Plumbing Concept – Raised Floor With Integrated Sump Pump System

This post documents the current concept for how the bathroom plumbing will function inside the cargo trailer conversion.
The bathroom floor will be raised approximately 8 inches, creating a dedicated plumbing cavity beneath the finished floor.
All bathroom drains—including the shower, toilet urine separator, and bathroom sink—will run inside this raised floor space.
Access panels will be built into the floor structure to allow maintenance of lines, fittings, and the sump pump.

System Overview

The raised floor provides enough vertical space to route all plumbing internally without mounting any tanks or lines under the trailer.
A 12V sump pump box will collect wastewater from the bathroom fixtures and pump it into the interior gray tank.
This approach keeps all plumbing inside the insulated envelope of the trailer for freeze protection and easier serviceability.

Plumbing Flow Diagram


                 ┌───────────────────────────────┐
                 │            SINK               │
                 │  (Drain enters floor cavity)  │
                 └──────────────┬────────────────┘
                                │
                                ▼
                 ┌───────────────────────────────┐
                 │     COMPOSTING TOILET         │
                 │   (Urine Separator Outlet)    │
                 └──────────────┬────────────────┘
                                │
                                │  Sink + Urine Combined Drain
                                ▼
                 ┌───────────────────────────────┐
                 │           SHOWER              │
                 │ (Low-profile drain to sump)   │
                 └──────────────┬────────────────┘
                                │
                                ▼
                 ┌───────────────────────────────┐
                 │     12V SUMP PUMP BOX         │
                 │  - Collects all bathroom flow │
                 │  - Auto pump activation       │
                 └──────────────┬────────────────┘
                                │ Pressurized Output
                                ▼
                 ┌───────────────────────────────┐
                 │          CHECK VALVE          │
                 │ (Prevents backflow from tank) │
                 └──────────────┬────────────────┘
                                │
                                ▼
                 ┌───────────────────────────────┐
                 │         INTERIOR GRAY TANK     │
                 │  (Mounted inside trailer)      │
                 └───────────────────────────────┘

Key Design Details

Raised Floor (8″): Creates a protected plumbing chase for all bathroom drains and the sump pump.
Access Panels: Built into the raised floor for serviceability of the sump pump, fittings, and drain lines.
Toilet Elevation: The composting toilet will sit at least 1 foot above the sump pump to ensure reliable gravity flow.
Sink Drain Tie-In: The bathroom sink will tie into the urine line to flush and clean the line and provide enough liquid volume to activate the sump pump float switch.
Shower Drain: A low-profile drain routes directly into the sump pump box.
Check Valve Placement: Installed on the sump pump discharge line before the gray tank to prevent backflow.
Interior Gray Tank: All wastewater is pumped into an interior tank for freeze protection and easier maintenance.

Why This System Works Well for an Interior-Only Plumbing Layout

This design keeps all plumbing components inside the conditioned space of the trailer, eliminating the need for under‑floor tanks or exposed plumbing.
The sump pump allows the gray tank to be positioned higher than the shower pan or toilet outlet, giving full flexibility in tank placement.

No exterior tanks: Better freeze protection and no road debris exposure.
Flexible routing: Pumped discharge allows tank placement anywhere inside the trailer.
Serviceability: Access panels ensure all components can be reached without tearing up the floor.
Cleaner plumbing: Sink tie‑in keeps urine lines flushed and reduces odor risk.

This mock‑up represents the current direction for the bathroom plumbing system and will be refined as the layout and tank placement are finalized.

Updated Diagram – Urine Separator, Sink Drain, Sump Pump, and Gray Tank System

This diagram shows the updated plumbing layout for the bathroom: the composting toilet’s urine separator and the bathroom sink both drain into the sump pump box.
The sump pump then sends all liquids to the interior gray tank, with a check valve placed before the gray tank to prevent any backflow.
The toilet sits elevated above the sump pump by at least one foot, ensuring reliable gravity flow.

System Diagram (Top‑Down Flow)


                 ┌───────────────────────────────┐
                 │     COMPOSTING TOILET         │
                 │   (Urine Separator Outlet)    │
                 └──────────────┬────────────────┘
                                │
                                │  Gravity-fed Urine Line
                                ▼
                 ┌───────────────────────────────┐
                 │       BATHROOM SINK           │
                 │  (Drain Tied Into Urine Line) │
                 └──────────────┬────────────────┘
                                │
                                ▼
                 ┌───────────────────────────────┐
                 │   COMBINED DRAIN LINE (1")    │
                 │  Sink + Urine to Sump Pump    │
                 └──────────────┬────────────────┘
                                │
                                ▼
                 ┌───────────────────────────────┐
                 │     SUMP PUMP BOX (12V)       │
                 │  - Collects shower water      │
                 │  - Collects urine + sink      │
                 │  - Auto pump activation       │
                 └──────────────┬────────────────┘
                                │ Pressurized Output
                                ▼
                 ┌───────────────────────────────┐
                 │         CHECK VALVE           │
                 │  (Prevents backflow from tank)│
                 └──────────────┬────────────────┘
                                │
                                ▼
                 ┌───────────────────────────────┐
                 │       INTERIOR GRAY TANK      │
                 │  - Receives all pumped liquid │
                 └───────────────────────────────┘

Side‑View Height Relationship


   [Composting Toilet]
            │
            │  (Urine Line)
            ▼
   [Sink Drain Tie-In]
            │
            ▼
   (Combined Drain Line)
            │
            ▼
   [Raised Shower Platform]───────────────┐
            │                              │
            ▼                              │
      [Sump Pump Box]  <───────────────────┘
            │   (Pumps upward)
            ▼
      [Check Valve]
            │
            ▼
      [Interior Gray Tank]

This layout ensures the toilet and sink both drain by gravity into the sump pump, while the sump pump handles all elevation changes needed to reach the gray tank.

Why the Sink Tie‑In Helps

Tying the bathroom sink into the urine line provides several benefits:

Flushes the urine line with clean water every time the sink is used.
Prevents salt buildup or odor in the urine hose.
Adds enough liquid volume to reliably trigger the sump pump float switch.
Reduces plumbing complexity by combining two low‑flow drains into one line.

Why the Check Valve Belongs Before the Gray Tank

Placing the check valve on the pressurized discharge line (not the urine line) ensures:

No gray water can flow backward into the sump pump box.
No contamination risk for the toilet or sink drain lines.
The sump pump remains protected from tank pressure or sloshing.

This updated diagram reflects the final intended flow path for the bathroom plumbing system and will be used as part of the full interior‑only plumbing documentation.

Build Notes – Floor, Insulation, and Bathroom Plumbing

Build Notes & Lessons Learned – Floor, Insulation, and Bathroom Plumbing

As I continue refining the design for the cargo trailer conversion, I’m collecting important details that will influence how the trailer is ordered and how the interior systems are built.
These notes focus on floor structure, insulation planning, and bathroom plumbing considerations based on research and reference videos.

No Dovetail for a Level Interior Floor

For this build, a flat, level floor is essential. This means the trailer must be ordered with no dovetail.
A dovetail is the angled drop at the rear of many cargo trailers, designed for loading low vehicles.
While useful for ramps, it creates an uneven interior floor and complicates cabinetry, flooring, and bathroom layout.

Choosing a non-dovetail rear ensures:

A fully level floor from front to back
Simpler installation of flooring, insulation, and cabinetry
Better support for the raised shower platform and tank placement

Interior Doors Must Be Raised for Floor Insulation

If the trailer does not come factory-insulated, the interior floor will be built up with insulation and subfloor layers.
This adds approximately 1.5 inches of height to the finished floor.

To avoid clearance issues:

Interior doors (bathroom, bedroom, etc.) must be raised at least 1.5″ during installation.
Dealers should not install interior trim — trim should be left loose inside the trailer.

This prevents the door from dragging on the finished floor and allows trim to be installed after insulation and flooring are complete.

Backer Boards Before Insulation (Video Reference)

In this video (timestamp 2:15):

Cargo Trailer Conversion – Insulation Prep

The creator explains the purpose of installing backer boards before adding insulation.
These boards provide:

A solid mounting surface for walls and fixtures
Structural support for areas where screws cannot bite into foam
Better rigidity and long-term durability

This reinforces the plan to include backer boards in key areas before insulating the walls and ceiling.

Urine Separator Plumbing Into Sump Pump (Video Reference)

In this video (timestamp 27:50):

Cargo Trailer Bathroom Plumbing – Urine Separator & Sump Pump

The builder demonstrates how the urine separator line from a composting toilet can be routed into the same shower sump pump box that feeds the gray tank.
This setup includes:

A dedicated urine drain line entering the sump box
A check valve to prevent backflow from the gray tank
Automatic pumping of both shower water and urine into the gray tank

This is a useful reference for integrating the composting toilet’s liquid output into the interior gray tank system without needing a separate container.

Summary

These notes help shape several key decisions for the build:

Order the trailer without a dovetail for a level interior floor.
Ensure interior doors are raised 1.5″ if insulating the floor after delivery.
Use backer boards before insulation for structural support.
Consider routing the urine separator into the sump pump with a check valve.

These insights will be incorporated into the final layout and construction plan as the build progresses.