homemade grey water tank...

[frenchie]

Would like to have feedbacks from members about the crasy idea I have to make my own grey water tank. instead of having grey water tank underneath the sink counter, in order to gain storing space Inside the van, I am planning to instal it underneath the van... Unfortunately, because of space issue, it seems like I'd have to make my own. I have plenty of space on one side, but very narrow,on the other side, so I could make one tank with custom dimentions, something like 40'' lenght x 10 inches wide x 10 inches high I would use plywood, then glued plastic sheets (I have for free at my job), Inside the tank, using silicone. Please comment if I am running for trouble, or if this could work out fine.

thanks.

 

[ccbreder]

how will you hang it to be secure while full of water?

 

[TMG51]

Why spend time making a long, narrow box, and trying to seal it in a way that won't fail with vibration and rot, when you could instead buy a long narrow tube that's made to hold water?

www.pvcfittingsonline.com/4004-100ab-10-schedule-40-pvc-pipe-5-ft-section.html

The volume of a 40" piece of that pipe would be nearly 12 gallons. Not quite as much as you'd have with 10" square vs a cylinder, but a lot less work and it cuts the variables right out.

Your usable volume will be very influenced by how level you park. If your drain from the sink is at one end of the pipe, you'll always have to park with the far end downhill in order to be able to use it at all. If your drain is halfway down the pipe, then you will only ever be able to use ~6 gallons of gray holding unless you're parked perfectly level.

 

[VJG1977]

It could be done but it will be hard to seal it to stand up to the vibration.  They do make odd shaped plastic tanks and will put the fittings where you want them.  This is a link to the first supplier I found.

Plastic-Mart.com
9 Gallon Rectangle Poly Tank
[font=Arial, sans-serif]9 Gallons
30.25"
10"
9"
R-R23W
$179.99[/font]

 

[BradKW]

Plastic-Mart.com

I've seen many builds source their tanks from the above link, and I believe they will make custom tanks to needed specs.

GaryGary made his own grey water tank, here's the link: http://www.buildagreenrv.com/our-co...d-the-fresh-and-grey-water-tanks/#comment-324
Read the comments at bottom too as he updated it. Personally I don't think it'll hold up over time, but he feels optimistic...

 

[masterplumber]

I would go the plastic pipe route, Not only easier to build, but easier to hang also. If you go to a plumbing supply house you can buy 6'' pipe instead of 4'' which is usually the largest I see at home centers. The supply house will have the correct caps and tees, along with any adaptors you might need also. You can go bigger, like 8'' or 10'', but then the cost starts to go up rapidly, especially for the fittings.

You actually have got me thinking. I have a Reliance square jug for gray water under my sink. If I hung a couple lengths of pipe under my trailer I could free up a bunch of storage space. I could probably do the same for fresh water, as it's only a little further for my hand pump to draw. I could get most of my front cupboard back!

 

[BradKW]

 

[frenchie]

ok, guys I think the plastic pipes could be a good option for me, cause plastic tank is way too expensive (for me here in taxland... Canada with our canadian curency.. it will be 30% more expensive. I never thought there was "caps" available to put at each sides... I will certenly look for such tank. Now to respond to masterplumber, I also have a reliance 6 gallons jug which I purchased to install underneath the sink, but will look more carefully, cause it may be "fittable" Under the van.... we will see. Also pehaps I can fit the fresh water tank there as well.

than you all

 

[highdesertranger]

x2 on the pipe. much easier then trying to custom build a tank. on another note I would bet that a premade tank is available. highdesertranger

 

[debit.servus]

If one wants 15 gallons of capacity at an affordable price look for a 15 gallon plastic drum, they could be slim enough to strap under the van.

 

[VJG1977]

ok, guys I think the plastic pipes could be a good option for me, cause plastic tank is way too expensive (for me here in taxland... Canada with our canadian curency.. it will be 30% more expensive. I never thought there was "caps" available to put at each sides... I will certenly look for such tank. Now to respond to masterplumber, I also have a reliance 6 gallons jug which I purchased to install underneath the sink, but will look more carefully, cause it may be "fittable" Under the van.... we will see. Also pehaps I can  fit the fresh water tank there as well.

than you all

When you calculate the price for a DIY PVC pipe tank, don't forget the fittings.  While the 5' section of 10" schedule 40 pipe was $76.81, two caps for it are $52.18 each, adapters and plugs are even more.  You are already up to the price of the ready made tank and you still have to add the inlet, outlet and vent fittings, pipes and valves.  smaller diameter pipe and fittings are cheaper but volume drops quickly.
10" = 13.6 gal
6" = 4.9 gal
4" = 2.2 gal
*volumes rounded to one decimal place

The formula to calculate the volume of a cylinder is [font=arial, sans-serif]π × r² × h. [/font]
For a 10 " x 40"
3.14159 x 25 x 40 = 3141.59 cubic in  
3141.59/231 = 13.6 gal

The big advantages of the grey water container under the sink:
simplicity, no pipes, vents or drains
little concern with freezing