PVC Water Tank & Gray Water Tank - DIY Sprinter Van Build

How to build an RV water tank or gray water tank from PVC pipe. For a complete write-up and PARTS LIST see: ourkaravan.com/pvc-water-tank/
The tank works great for our shower water system. Word of caution: I was concerned that the air vent would not be located high enough above the tank to prevent water sloshing and possibly coming out of the vent, but I haven't seen that yet. I used threaded fittings here just in case I needed to extend the breather up higher...the only such place being the engine compartment. Just be advised that I haven't had the van in really precarious offroad situations yet and the air vent may need to be extended higher depending on your use case. Using threaded fittings makes this possible.
Website: ourkaravan.com
Instagram: / our.karavan
Music:
Clover 3 - Vibe Mountain (KZbin Audio Library)
Rolling Heads - Unicorn Heads (KZbin Audio Library)
Note: This video contains affiliate links for which I may be compensated. Please know we only promote products we actually use and believe in.
#rvwatertank #diysprinter #pvcwatertank

[@kevinshea4776]

Absolutely love the 5 year old shop foreman! I have been watching your build from the beginning and think it is great that you include your daughter where you can! Priceless!!

[@ourkaravan]

Thanks Kevin! It's her van, so I'm sending some accountability her way. I do love it when people ask if I built the van myself and she quickly steps in and says she helped build it. :)

[@shockingguy]

Yes it is important and imperative to absolutely include your kids when Doing stuff especially mechanical things this translates into far more as the kids grow up and especially giving girls a chance is highly important because they get pushed aside a lot when learning these kinds of things bravo sir bravo

[@ourkaravan]

I agree completely!

[@nmartin5551]

What a great idea for those places under a sprinter where you almost can’t put anything.

[@donjones3355]

Ken, Great job as always. You are lucky to have such a good helper. Thanks for taking the time to make the video and share.

[@ourkaravan]

I am, and she's a good listener. I think it's important to involve your kids in your daily activities as much as possible.

[@VanGoNow]

Great idea, great install!

[@larrys710]

Nice job and great idea! Thanks for posting this. I'm looking forward to the next one on the plumbing connections and to see what you're doing for hot water.

[@ourkaravan]

Thank you Larry! I'm not too far out from getting that system completed.

[@DaresDrives]

Great idea, thank you for taking the time to share!!

[@ourkaravan]

You are welcome, thanks for watching!

[@lavendereyesgal1125]

Thank you for sharing this. I’m about to but a van to convert into a home for my dogs and I. I needed this information. Very Informative and creative.

[@ourkaravan]

That’s great, thank you and good luck!

[@YourpainRx]

Thank you for the idea!!!

[@slavomirdzieciatkowski8811]

This is a great idea! We're building a Transit and your tank setup will be very helpful for a gray water tank. Thanks!

[@ourkaravan]

Nice, thanks for the comment! Let me know how it comes out.

[@myster624]

Great idea, I’ve been stuck for an idea. Thanks so much

[@ourkaravan]

In a tight space, I think this is a good way to go. However if a production tank fits in the space (like in the voluminous space on the driver's side of the van), it's way easier to buy a tank.

[@functionalvanconversion4284]

What a great idea! You could actually heat it once glued and contour Incase you wanted more clearance. Thx

[@SallySparks]

Awesome, Ken. It has been a while since I visited your content, and I'm glad to see you're still at it.

[@ourkaravan]

I hope you enjoyed it, I far prefer the creative process of making travel videos over diy videos. 😀

[@DiegoSantos-kw4vd]

Brilliant!

[@ericmueller1987]

Great idea!

[@TheCocktailTimes]

Great idea

[@greglewis8843]

Great idea for a water tank so simple but brilliant. Had to look up what a plus is called riv nuts here in the UK thanks

[@ourkaravan]

I’ve seen about six others implement this and they seem happy. Thanks for the comment!

[@marcelellis6037]

Brilliant. I had ame idea, tried to explain to someone else what I had in mind but failed; BADLY!!!

[@michaelheppler2193]

Brillant!!! I am going to build one for my gray water. Im a plumber and did not think of that. Great job thinking out of the box. Im gonna put and auto drain on mine Remember to paint the PVC because UV rays will make it brittle even thought it is under the van

[@ourkaravan]

I think gray water is a great use of a PVC tank. Good tip on the paint. I assumed because the plastic was 3/8" thick that I wouldn't have an issue, but perhaps that's not the case.

[@alanwestport]

@@ourkaravan No direct sunlight means no need to paint.

[@spleerfloof]

@Michael Heppler What is an auto drain?

[@JohnMason-Hill]

Awesome!!!!

[@MitchellCamps]

Great idea, I think I am going to do this as well. Thank you for the idea, did not think of this. I was going to buy a welder and try welding a tank.... lol! I may still try to weld a few thing, but I probably shouldn't start with a tank

[@ourkaravan]

Welding is a great skill to have, but I'm assuming you won't want an aluminum or steel tank, you'd want stainless steel. That one is more difficult to weld.

[@kristeljessaguijo5638]

great! 👏👏

[@davidlundy5007]

In the same location I put in a 15 gallon under mount tank from Class A Customs that fit well. I had to build an angle frame to support it. It is 3.5” from the muffler though but so far is fine. Great job.

[@ourkaravan]

Thanks David. I think I looked at that same tank but couldn't get it to work with the step. Glad to hear yours hasn't melted to the ground either. :)

[@davidlundy5007]

ourkaravan I’ll let you know if it does, lol. I was trying to come up with some kind of heat shield 36” long. Haven’t been on a long trip yet after install, well pleased though how it turned out. I also put their 20 gallon on the other side for the shower.The price was excellent. Also built my angle and flat bar cradles from the RB Components blueprint.

[@davidlundy5007]

ourkaravan you are very lucky to have your daughter to help. I had nobody.

[@steveedwards8915]

Great design! Thanks for sharing. Might I respectfully suggest: A top-mounted siphon tube that extends to the bottom front of the tank might better facilitate thorough emptying with the pump? Or a rearward siphon tube, if that better suits your purpose. Thanks again...

[@ourkaravan]

You could certainly try it. The bottom port was pretty easy to implement.

[@luvnotvideos]

I absolutely love your series. You put so much thought into everything and have a knack for making it easy to follow. I know this was filmed right before the SHTF, but have you had a chance to utilize the tank yet? If so, have you found 8 gallons to be enough for your purposes? If not, how long do you expect that much water to last on a trip?

[@ourkaravan]

Hi, thank you, I very much appreciate that! I have used it quite a few times. If I could have any capacity tank, I would say somewhere around 10-12 gal would be perfect. (Mostly because I don't care to carry a bunch of water weight around.) I'm at 8.8 gallons. And I'm talking shower capacity only; as you probably know I have a completely separate water supply at the sink. It's enough water to get at least a couple of showers each between my daughter and I. I'd say she uses twice as much water due to the length of her hair. I can't say exactly because I usually refill after a few showers. I went over this system in a bit more detail in my most recent travel vlog to Colorado. kzbin.info/www/bejne/goTKoX2oetONgMU Thanks again and take care! -Ken

[@suhrinc873]

Hello, Thank you for the time in producing & publishing your experience. I've used a few of your wonderful ideas. This PVC tank idea looks great. My question is about water noise while traveling, just wondering if internal baffles would be worth the hassle. Do you feel the water sloshing in the pipe while traveling with different water levels?

[@ourkaravan]

I haven’t heard it yet. I only see it being an issue if the storage vessel was inside. Thank you for the kind words!

[@ARepublicIfYouCanKeepIt]

After initially considering manufactured tanks, I decided to create a tank _system_ out of PVC pipe. I did my research to ensure the suitability for potable water applications. Once satisfied, I developed a layout for a _system_ of tanks that could be used for freshwater and/or grey water storage. The thinking here is to maximize freshwater holding capacity for anticipated long duration boondocking, emergency situations, etc.. All tanks can either be separated or interconnected, depending on need. Advantages include: • *Cost* - PVC pipe and associated caps, fittings, etc. are much less expensive than large volume tanks. • *Availability* - All system components are commonly stocked items in most big box home centers. This is especially useful if/when repairs are needed while on the road. • *Customization* - Configurations and sizes are limited only by one's imagination. • *Flexibility* - With the tanks all interconnected, valve position determines function (fresh vs. grey), as well as capacity. • *Inertia* - Liquid stored in several small tanks simply doesn't slosh around due to vehicle movement, especially when braking! My rig is a 2011 Ford E350 cutaway with 12' box, so my tanks are tucked up neatly between the floor beams that connect the box to the chassis frame. Transverse mounting minimizes water movement when driving even more and the entire system is incredibly easy to design, build, install and maintain. For those who are interested, the formula for volume of a cylinder is: V = πr²h, where 'r' is the radius of the cylinder and 'h' is the height of the cylinder. 'V' is then a cube of the units used. For those of us in the U.S., simply divide cubic inches by 231 to convert to gallons. In this case, since we know the diameter of the tank (8") and the capacity (~8.5 gal.): • 8.5 gal * 231 = 1963.5 in³ • 1963.5 / (3.142*4²) = 39.05" for the length (height) of the tank. Another advantage of PVC over manufactured tanks is UV light. Since PVC is opaque, algae growth is inherently inhibited. For those who picked up on the fact my system capacities can be changed, more or less on the fly, rest assured that I clean and disinfect grey water tanks before converting them to freshwater holding. However, with an ultra-filtration system (0.02µ) that captures 99.9% of viruses, bacteria, cysts and protozoa, I could fill my tanks from even insecure water sources and be just fine. The only things my system can't filter out are liquid contaminants such as chemicals, petroleum products and the like.

[@ourkaravan]

Thanks John for sharing. The internal diameter of the 8" Schedule 40 PVC is 7.942" for sake of people's calculations. This won't take into account the bell-shape of the PVC caps so I figured I'm gaining a small amount of volume there too. But 40" is roughly the total length of my tank including end caps, limited not necessarily by the cavity under the van but also the rear mount for my Powerstep. I meant to point out the UV resistance as well. It irks me that all of the drinking water hose is clear, which means it facilitates algae growth. I found some white drinking water rated hose and that's the best I could do. Mine is for shower water but I still didn't want algae in my lines!

[@ARepublicIfYouCanKeepIt]

@@ourkaravan Yours has always been one of the best van builds on KZbin. It's in the same league as Greg Virgoe and George ("Chip") at Humble Road. Be well and best wishes.

[@ourkaravan]

Very kind, thank you John. I enjoy the fact that the three builds are entirely different. Greg is building an RV, while my van is closer to what the industry calls an "adventure van." George's build is art, and is the result of combining the best materials and essentially limitless time to make everything perfect. By contrast, I am a single parent raising a 5 year old, working full-time, traveling and recovering from the significant loss of a spouse to cancer. Time nor money is limitless, so my build is what you get when you strike a compromise and build to the best of your ability with quality materials, but knowing that turning each bracket into artwork isn't practical given time constraints. But it also happens to be very achievable and repeatable by others. I love getting photos of people's work that was somehow inspired by mine. I'm super happy with the functionality of the van. And damn I'm happy with how it came out given my next to zero construction experience. I have zero regrets on this project, and appreciate all the support from you and others. -Ken

[@rhyleymcgrath788]

Hey John, Do you have plans for your system floating around? The under vehicle layout of my van is...inconvenient, to say the least. I think something like what you've mentioned would work well! Let me know

[@ARepublicIfYouCanKeepIt]

@@rhyleymcgrath788 Plans for my rig wouldn't be of use to those with different vehicles. The configuration under each vehicle will determine where tanks made from PVC pipe can be mounted and interconnected. What year, make and model is your van?

[@ricwright1492]

I also had that idea. Great install, have you thought about the plastic “tank” chafing against the metal of the undercarriage? I’m sure this will last at least the summer depending on how much you drive. Good basic idea just needs fine tuning.

[@ourkaravan]

Chaffing only occurs when things are loose. The tank is cinched down and may as well be part of the body. Also, the plastic is extremely thick. Rubbing through isn’t going to happen.

[@duncansarmy]

Ric your comment comes across very patronising

[@jimdearborn2539]

Nice, but I didn't notice any anti-chafing material on the support straps. What are your thoughts?

[@ourkaravan]

The pvc is so thick it’s not a concern. On a regular thin walled tank it would be critical.

[@jassdsu]

I like your style, what do you think of the long term effects of pvc being exposed to heat such as the exhaust? That’s the one question mark for me. Lastly- an air vent? Did you install one? Awesome job- clever out of the box design ideas.

[@ourkaravan]

Yes, there is an air vent on top of the tank. I purchased some self-adhesive reflective tape to use as a heat shield, but have not found it necessary to install it. But you can always add it if you like. Thanks for watching!

[@mayjortom3770]

while watching this awesome video, I noticed the little metal corner joint on your step between the main floor and the step itself. If you understand what I am describing, any chance u could let me know where did you get that metal right-angle floor corner or what is it called? I been looking for something rather durable as that step is a very high traffic area in the van. Sorry is the question isn't related to the topic in the video. Cheers

[@ourkaravan]

No worries. Are you referring to the aluminum angle I used between the step well and the main floor? If so, it's some 1/16" thick and 2" wide that I'm pretty sure I picked up at Home Depot. They usually have a small section of steel and aluminum in the hardware aisle.

[@dustystarr2297]

Awesome idea!! Curious why you didn't use a hole saw instead of a step-bit?

[@ourkaravan]

I probably didn't have the right one...either is fine.

[@tothetrail]

Ken, thanks so much for these videos. Love the shop helper! Do you have a plan to figure out how much water is left in the tank before someone starts a shower? I see they make clear 8" end caps, but are $300. Maybe a sight tube? Or a little WiFi water meter? But those only work when you have service. Or a digital water meter? But those look to be inconsistent at low flows. And have you figured out your system for gravity fill yet?

[@ourkaravan]

Hi Jen, My original idea was to tap the top and bottom of the PVC end caps with some 1/4" NPT to barbed elbows, then add clear tubing between to act as sight tube. However I'm starting to wonder if the Garnet tank monitors will work. Those are circuit boards that adhere the outside of the tank, making it super easy to install. The thickness of the plastic had me concerned but I read this on their site: "Does it work on other types of tanks? It has to be a plastic tank with a wall thickness of 3/4” or less, and the liquid inside must be water based. It will not work on metal propane tanks or on gasoline tanks." So sounds like that might be a good way to go. I ruled out the other solutions that only provide 3 or 4 levels of the water...not very helpful. I haven't had a chance to work on the fill yet. I have some ideas but need to figure out the parts. My shop helper keeps me on my toes, that's for sure!

[@tothetrail]

@@ourkaravan Thanks. Yes, I have the SeeLevel Garnet monitors on my motorhome tanks and they work pretty good, way better than the previous system I had. But those tanks are flat sided, so was wondering how well they would work on the rounded PVC pipe or even the bell shaped end. The only issue I've had with the SeeLevel is with the LP gas level. It seems to be all over the place, but that may be due to the pressure caused by heating and cooling. But you probably wouldn't have to worry about the LP monitor. Other than that, I have had to reset or re-calibrate the gauge a few times when it was reading some error code, but it was resolved, and it seems to have been working fine the last couple of years. I really would rather just have a way to see the level visually, but the issues with algae growth in clear plastic have me thinking about some other method.

[@ourkaravan]

I'm thinking either really low tech, like a sight gauge, or high tech, like ultrasonic measuring...all of the in-between solutions that involve 3 or 4 point data collection isn't worth anything, IMHO. The problem with the sight gauge is having to look under the van to check, and the fact that it will introduce some level of sunlight into the tank. Now what's cool are some of the ultrasonic solutions I've seen. There are some really cheap wireless/smartphone Arduino solutions. Want to try it? Home-schooling is kicking my butt. :)

[@ramzizaz]

Are you planning on winterizing this when you go to cold climates or do you think it will not freeze

[@ourkaravan]

It will freeze. That's why my sink and drinking water are all inside, as those are critical. If this shower water tank is frozen, no biggie, particularly since our shower is not inside the van.

[@jmmcmahon]

the air vent you installed will that also allow water to pass through, i thinking about using it for my fresh water tank and if i over fill the tank will that air vent act as a overfill release, too. thanks

[@ourkaravan]

Yes, exactly. Water spills from it signaling that my tank is full.

[@KentFleshman]

@@ourkaravan do you have a way of monitoring tank level?

[@ourkaravan]

I do not. That would be nice!

[@marlenen6130]

How much water does that tank hold? My Aliner has a 12 gallon fresh tank but has just gravity for gray water. Was going to join Harvest Host to camp, but they require a built in or mounted gray water tank to use their service. I have a porta potty to meet the toilet requirement, but the no-gray tank thing bars me from HH. I just need a way to get 5-8 gallon gray tank.

[@ourkaravan]

Hi, mine is 8.8 gallons, which was mostly constrained by one of the legs of my entry step. Obviously the longer you go from the 40" of my design the more water you can carry. There are some online calculators you can use to calculate the volume of water stored in a pipe of given diameter and length.

[@marlenen6130]

@@ourkaravan thanks so much!

[@ourkaravan]

👍

[@reggiecondell]

I don't see any discussion/questions as to the tank volume (at least I couldn't any). I calculate an 8" ID pipe holds 2.6 gallons per lineal foot. Your tank appears to be 4 feet long - so do you figure that you have about 10.5 gallons? Clever solution. BTW - what occupies the space on the driver's side between the frame and the outer body? Thanks - good video as usual.

[@ourkaravan]

I calculated about 8.8 gallons. The math works out to 8.6 but there is a bit of additional storage in the bell shaped end caps. The drivers side is wide open for tank mounting. I wanted to get some weight on the other side, hence why I went this route. Thanks for watching!

[@morgananderson9647]

@@ourkaravan Hello- I've learned a lot watching your vids. Thanks for sharing!!! I am interested in doing a similar tank on the 170 EXT van. I also want to have the retracting step like your setup. I'd like to get additional capacity Perhaps linking 2 in series? I do a lot of skiing in cold weather climates. I'd be grateful if you share, If you were going to make it so water would wouldn't freeze do you have any solution that come to mind? I welcome your insight on both subjects. Thanks in advance for your consideration- M-

[@ourkaravan]

It wouldn't be difficult at all to link tanks. A simple barbed fitting that passes between the two tanks would do it. I didn't put any anti-freeze measures on mine because I figured if it's that cold I probably won't be showering outside (no inside shower in this van). However any of the normal tank heating techniques would work such as the thin-film wire or the electric mats that provide some level of tank heating. Good luck and thanks for watching!

[@mosoworks619]

How are those tanks holding up? (Literally) it's almost a year now. Great idea

[@ourkaravan]

Not a single issue! Works great for our needs.

[@1lifewanderlust]

We all need a foreman as cute 🥰 such a great little helper!!! I wonder if this PVC will hold up to Canadian winters for grey water. Will it freezes when temperatures drop?

[@ourkaravan]

We are working on her van build skills, maybe she will build van #3 for me. 😀 While the plastic is much thicker than a normal rv tank I would think it would be just as susceptible to freezing. I would take the same precautions as with a normal tank.

[@spleerfloof]

I really like this idea, I’m thinking of a gray water tank for a 2019 ProMaster. Could you elaborate on the fuel tank straps? Where would one purchase those? I haven’t checked out your website yet, I will do that next. Maybe my question is answered there, thank you for the info.

[@ourkaravan]

Some of the cutoff pipe was used on my friend’s sprinter to serve as a graywater tank. Works great. Here’s the info: ourkaravan.com/pvc-water-tank/

[@spleerfloof]

@@ourkaravan Thanks, found the Amazon link for the straps :)

[@ourkaravan]

👍

[@simonlynchsae]

Won't you have heat issues with the diesel filters so close to a pvc tank?

[@ourkaravan]

I bought self adhesive reflective insulating tape for that purpose but I don’t think it’s necessary to use it.

[@MattVoda]

Do you think thinner (and cheaper!) DWV or 'drain and sewer' pipe would work okay for this?

[@ourkaravan]

Hi, depends on what you’re using it for. If for drinking water supply, no. I believe drain pipe has contaminants that can leach into the water.

[@MattVoda]

@@ourkaravan I’m pretty sure it’s the same plastic, polyvinyl chloride, with thinner walls. Foam core introduces some exotic foam chemical(s) I’d be uncomfortable drinking, but should be completely contained by the two PVC walls. Anyways, I’m using it for gray water so no concerns there. I bought some 4 and 6 inch to try! Can you advise on achieving a good mating between the PVC tank walls and the fittings / connections / adapters? Wish there was more footage of you installing those. With the thinner-walled DWV pipe, there’s not a ton of depth to cement a connection with. I’m wondering if there’s a kind of washer or flange that can help secure the fitting to the tank cap. Thanks for the great video and plans!

[@ourkaravan]

If being used for gray water than I see no problem with dwv. Because the tank will not be under pressure I don’t think you’ll have a problem with the glued joints leaking.

[@frejuarez5452]

Does that air valve get water out? If the tank is full to the max?

[@ourkaravan]

I thought I might have a problem with the valve leaking, possibly from water sloshing or going up a super steep incline, but I've seen no evidence of it. (The pipe is so dusty I think I would see evidence of water.)

[@RoadtoPitches]

Hey ourkaravan, wondering if we could share a snippet of your video at 8:38 with our community? We will be publishing a video soon on our water/shower system in our box truck conversion and we also considered a PVC water tank! Of course, we'll tag you in the video and add credits in the description. Thank you! - Sachiko

[@neredeyizhocam]

it looks like 12" (300mm) wide pipe. and not 10feet only 3 feet (100cm)? am ı seeing wrong :D is there any wrong measures about this?

[@ourkaravan]

8” pipe and about 40” long

[@TednLisa]

Is there a video on how to fill the water tank?

[@ourkaravan]

I plan to sneak it in at the end of my next video. There’s a 90 elbow on the inside of the slider step exactly as you saw under the van. Right now I have a garden hose adapter threaded into that with a set of hose quick connects and a cap to close it off. That lets me pressure fill but isn’t the best for gravity fill when I’m on the road, so I’m coming up with something better. Because they are standard pvc fittings you can literally make it anything you want it to be.

[@TednLisa]

ourkaravan Thank you really liking your videos

[@ourkaravan]

awesome, thanks!

[@thomasdarby6084]

Great job, but I would NEVER use any plastic except food-grade for fresh water storage. Over time and in hot weather, plasticizers (cancer-causing agents) can leach into the water. This does not happen in house installations, because the water is continually flowing, and the pipes are generally kept cool in the walls or under the floor. I recommend a stainless-steel tank, or contact U-Line for the many custom-order tanks made for food storage or liquids. I'm sure you could find one that fits. Yes, it would be expensive, however with what you already paid for the van and your internal work, why cheap out on the tank, and your health?

[@BobCollins42]

I must have missed it, but where is _your_ gray water tank? Thanks!

[@ourkaravan]

I don’t have one…yet

[@jibran89]

does the water move around alot?

[@ourkaravan]

No idea! I’ve never heard or experienced water sloshing.

[@cluek9780]

Ummm….. where’s the heat shield from the exhaust? Follow up?

[@ourkaravan]

I bought material to make a radiant barrier heat shield but it’s not needed. The tank works great!

[@durangarc]

How many gallons can it hold?

[@ourkaravan]

8.8 gallons. Without the step you could make the tank much longer.

[@CanadianTexaninLiguria]

Lol - using your idea to build a horseshoe shape tank over the wheel well

[@ourkaravan]

Nice, let us know how it comes out!

[@traciuniquestylefeliciano7696]

I love it but to fast I don't know what part i need...can you make another video that is slower and add voice directions.. please Thanks 🙏

[@ourkaravan]

If you click the link in the description below the video it will take you to my write up, complete with all parts required. 👍

[@vinceocratic]

What’s the storage capacity?

[@ourkaravan]

This one is 8.8 gallons, as I was constrained by it fitting between the pivots of the Amp Powerstep.

[@vinceocratic]

@@ourkaravan Thanks for the reply and I appreciate the content

[@poerava]

Not the ideal tank. This tank allows a thin layer of the water to remain at the bottom of the tank and grow bacteria. Best to get a tank with a gradient that allows the water output nozzle to be at the lowest point of the holding unit. I guess this could work if they parked on a steep incline to drain water.

[@ourkaravan]

Literally no one makes a tank to go in this narrow location. Had to turn to diy.

[@poerava]

@ourkaravan I hear you. I bought this tank and realised it wouldn’t fit. trailerpartsdirect.com.au/shop/canopies/tray-accessories/40l-tourer-tray-water-tank/?currency=AUD&gclid=EAIaIQobChMI48msqcCa7wIVkwByCh05hQQQEAQYIyABEgL5g_D_BwE Now I’m looking for a similar one to yours. Have you considered selling your tanks?