Gray Water Tank and Winterized Bus Build - inside or under?

[Green Machine]

Originally Posted by Mudhutwarrior

I was about 30 miles up from Portland (Boston for any Mainer) About 15 mile inshore. New Gloucester. Still cold most of the winter. If I didn't make it clear it was a coach with luggage bays. If your doing it with a skoolie you will need to wrap the armorflex. It will work but deteriorate over time if not protected. Not sure about reliable heating either. The mention of straw bales earlier is a good one one. On the sides at least. Mat heaters would work but again they need to be protected and you won't be able to use a product like armorflex. In maine people that have trailer with skirting will sometime add a box around the exposed plumbing
Like pumps and use 4"dryer vent from the supply air over to the box. Keeps just enough heat to prevent freezing. Something along those lines might work also.

Yeah, I've definitely heard people jokingly refer to anything close to Portland as "Boston" or "Northern Massachusetts"! I'm originally from Rhode Island, so wont throw any stones myself

Your mention of a box around the plumbing is what I was picturing in my mind, to have an underside tank and construct an insulated box (plywood?) around it to provide some additional protection from the elements on top of better insulation. That plus a heater of some type probably would work from what I am gathering.

Your coach setup definitely helped, already having something enclosed to place the plumbing in, but beyond concerns of clearance during travel I wonder what negatives a plywood box surrounding an underside tank might have on a skoolie? And even if loss of clearance were an issue, my likely scenario would allow for removal of the box when in "travel mode" anyway as any travel would favor either warmer locations or warmer seasons.

Originally Posted by turf

midsummer this year, half of the heating pad sandwich was hanging down to the ground. the adhesive side stayed on the tank, the heating wires and the lower rubber half fell off.

Per "turf's" experience with the adhesive back mat heaters, I wonder if the heater pad can be reinforced with aluminum foil tape to help prevent the delamination? Guessing the adhesive holding the layers together can't quite cope with long term temperature swings and the weight of the wiring/outer rubber layer

[roach711]

One of the full timers who used to frequent this forum protected their waste tanks and fresh water supply hose with ice dam heat wires wrapped with reflectix insulation.

Insulation alone won't do the job unless there's some source of heat.

[PNW_Steve]

Originally Posted by Green Machine

Yeah, how much antifreeze you would go through did come to mind if the scenario is full-time winter living. Currently I've no idea of the cost of the stuff, how much would be needed per tank full, and what that would all add up to!

The electrical heating options coupled with insulation might be the best overall, need to look into this more!

The cost in my area is $2.50-$3.00 a gallon.

It is a good stopgap for short term cold.


If you are living full time in cold weather the only options are heated/insulated tanks or pee outside.....

I have had success with the "peel and stick" heater placed on the tank and covered with 1 1/2" closed cell insulation.

In my rig, the fresh water tank will be under the bed and the grey tank under the floor. The grey tank will be surrounded by 1" closed cell foam and have a tank heater .


My hope is that all of this is a waste of time and money because I hope to manage to stay South during the Winter. We'll see how it plays..

[Buzz Nichols]

Originally Posted by turf

there was a link in the post right after mine to a similar product that i used.

mine was like 24"sq and it worked well. it just isn't weather proof. its 2 layers of rubber with heating wires in between.

midsummer this year, half of the heating pad sandwich was hanging down to the ground. the adhesive side stayed on the tank, the heating wires and the lower rubber half fell off.

i don't have a picture of the delaminated pad, but i do have a picture from before when i installed it.

If your AC situation allows, there's a 110 version of this same pad that's intended to keep flats of sprouts warm in the greenhouse before the last freeze of spring. It's essentially the same critter, but way cheaper.

[Green Machine]

Originally Posted by Buzz Nichols

If your AC situation allows, there's a 110 version of this same pad that's intended to keep flats of sprouts warm in the greenhouse before the last freeze of spring. It's essentially the same critter, but way cheaper.

Always happy to know about the cheaper version of a product where the only real difference is how it is labeled and marketed compared to the more expensive version!

[Green Machine]

Originally Posted by PNW_Steve

The cost in my area is $2.50-$3.00 a gallon.

It is a good stopgap for short term cold.


If you are living full time in cold weather the only options are heated/insulated tanks or pee outside.....

I have had success with the "peel and stick" heater placed on the tank and covered with 1 1/2" closed cell insulation.

In my rig, the fresh water tank will be under the bed and the grey tank under the floor. The grey tank will be surrounded by 1" closed cell foam and have a tank heater .


My hope is that all of this is a waste of time and money because I hope to manage to stay South during the Winter. We'll see how it plays..

Seems like cheap enough insurance to keep a gallon or two of the anti-freeze if not planning for full-time freeze protection, but want to have an option in a pinch.

Your setup sounds like one of the routes I'd be considering, to keep fresh water internal and winterize the gray underneath. Will have to make final decisions once I've an actual bus to start figuring out floor plan on, but with my plans favoring a full size skoolie I'm sure I could sacrifice some interior storage for keeping the fresh water plenty warm under a bed or cabinet.

[Iceni John]

Does anyone here use waterbed heating pads to prevent tanks freezing? All four of my tanks hang under the bus, but they are sheathed in 1/2" plywood on their sides and underneath mainly to protect them from road debris. I could conceivably slide some WB heaters in between the tanks and the plywood floors, and 300W per heater should be enough to prevent freezing.

John

[PNW_Steve]

I have installed this type of tank heater with good success: https://www.amazon.com/Facon-Holding.../dp/B01MT9EUG9

[o1marc]

Originally Posted by PNW_Steve

I have installed this type of tank heater with good success: https://www.amazon.com/Facon-Holding.../dp/B01MT9EUG9

12 volt compatible and only 65w, I like.

[Sevier]

Originally Posted by o1marc

Put antifreeze in the gray tank.

And so when you dump your grey tank, you do so in a controlled manner in a recycling facility? Or do you dump antifreezed grey water into the ground?

[peteg59]

Originally Posted by Sevier

And so when you dump your grey tank, you do so in a controlled manner in a recycling facility? Or do you dump antifreezed grey water into the ground?

RV antifreeze is non toxic. Doesn't mean I'd drink it, but it is safe to dump down the drain, or at a RV dump site..

[kazetsukai]

Ah, this thread. This. We learned a few things this winter so far, and are looking to redesign some of the drainage downstairs. We're currently fighting freezing plumbing. It isn't horrific, but I've had the shower and sinks back up on us once. Fixes below.

We've obtained pipe insulation:
https://www.amazon.com/gp/product/B071RSVB43 3" 1/2, just right for 3" pipe
https://www.amazon.com/gp/product/B01LWVNCBT 2", too small for 2" pipe, looking for something a little bigger.

On the 3" drain pipe I'm going to use some tank heater pads which are close in diameter to the pipe in combination with the above wrap:
https://www.amazon.com/gp/product/B0861MNLP8

For 2" drains I'm going to wrap heat cable around the pipe, then the above wrap.
https://www.amazon.com/dp/B0732YXBM9

Also replacing all of the hard 3" and 2" PVC runs with Flex PVC, because some of our runs cracked when they froze. Flex will not crack, only the hard stuff will, so I will cover that really well and heat it when necessary.
https://www.amazon.com/gp/product/B000OLCH92
https://www.amazon.com/gp/product/B0042L52AQ

Then on the holding tanks themselves I'm using pads appropriately sized.
https://www.amazon.com/gp/product/B01MT9EUG9

When I redo the lines, I'm going to try to place the gate valves right at the tank as to keep the runs themselves empty. All a big effort, I'm waiting on a couple warm days to do it all.

What we've learned in a nutshell:

• Drain often, empty pipes don't break upon freeze.
• Installing a skirt is very effective, blocking wind from flowing underneath.
• Design your drainage to go directly into your holding tanks at an as-steep-as-possible angle. Ideally they should be empty until the tanks overflow.
• Place the gate valves as close to the tank as possible. Consider right at the tank outlet, using cable-driven or electric gate valves. The objective being keeping the final drain pipe between your holding tank and the drain hose normally empty.