1000 gallon tank weight foam

[goosegunner]

Working on my tank Room. I have the 1000 gallon tank sitting on treated 2X12's that are 5 feet wide. They are six layers thick to elevate the tank to provide room for bottom connections and room for insulation. That gives me an area of about 10 square feet or 1000 pounds/ square foot or about 7 psi.


What do you think about putting 2" high density foam under the 2X12?


I want to insulate the concrete floor under the tank but don't want it to settle into the foam.

Foam is rated at 25 psi but it seems unlikely to not squish under the weight of the tank.

gg

 

[Bad Wolf]

Actually 1000 gallons x 8.28 = 8280 pounds /10 sq ft = 828 lb/sq ft /144 = 5.75 psi

I'd roundup to 6 psi. If you want to do a test take a piece of 2x4 cut 8 1/2 long place it on the foam, now stand on it. If you weigh 180 like I do thats 6 psi. The foam won't even notice it.
I've got 4" of foam under my 1200 gallon tank, bottom temp around 150 for the last 3 years and it hasn't budged.

 

[Frozen Canuck]

Go ahead & put the foam under Goose. The lumber will help to distribute the load (reduce pressure points). Remember to stagger the joints in the lumber or run alternate rows in opposite directions first row north/south second row east/west & so on (to further add to the strength). Heaterman puts his Garns directly on foam & I have not heard anything other than it works well, from him. The only caution I would mention is that you said the lumber is treated...you will need a foam that is rated for contact with pressure treated wood or a barrier (sheet of poly) between the foam & the wood. Hope this helps.

If you still have doubts that the foam will hold up (you shouldnt given the above description) there are even higher density foams on the market, bear in mind they will cost more & will also be more brittle (quite a bit more brittle). However being higher density they will carry more psi than say standard Dow blue board.

 

[Frozen Canuck]

Sorry Goose, misunderstood your post after re reading I see you are using the lumber to make skids not a pad under the tank, doesnt change anything foam will work fine.

 

[woodsmaster]

Actually 1000 gallons x 8.28 = 8280 pounds /10 sq ft = 828 lb/sq ft /144 = 5.75 psi

I'd roundup to 6 psi. If you want to do a test take a piece of 2x4 cut 8 1/2 long place it on the foam, now stand on it. If you weigh 180 like I do thats 6 psi. The foam won't even notice it.
I've got 4" of foam under my 1200 gallon tank, bottom temp around 150 for the last 3 years and it hasn't budged.

You forgot the weight of the tank itself, but yes it will work.

 

[goosegunner]

Thanks I will try and get a piece under each skid.

I was originally going to just have the 6 layers of treated wood on the concrete and then cut foam pieces to go around the wood. It will probably stop heat conduction better if I can even just put one layer of 2" under the skids and then stack pieces around for additional layer.

gg

 

[DaveBP]

If you're going to box in your storage tank with insulation of some sort, the air around the tank is going to be pretty hot at times. I'm betting the compressive strength of the foam is NOT measured at those temps. The foam gets softer when it is hotter.

I believe the professional Garn installers use commercial high density foam, not LowsDepot foam , to set the boiler directly on. I think you want to insulated between the boiler tank and the planks and foam below them so that the foam the sleepers are resting on can stay cooler. May not be a deal breaker but it couldn't hurt, just in case.

If the tank settles some over time it could strain plumbing connections.

 

[goosegunner]

If you're going to box in your storage tank with insulation of some sort, the air around the tank is going to be pretty hot at times. I'm betting the compressive strength of the foam is NOT measured at those temps. The foam gets softer when it is hotter.

I believe the professional Garn installers use commercial high density foam, not LowsDepot foam , to set the boiler directly on. I think you want to insulated between the boiler tank and the planks and foam below them so that the foam the sleepers are resting on can stay cooler. May not be a deal breaker but it couldn't hurt, just in case.

If the tank settles some over time it could strain plumbing connections.

Yes I should be able to get a layer of fiberglass between the bottom of the tank and the plank that the legs are sitting on. I think I will put just one layer of 2" foam on the concrete directly under 4 layers of treated 2X12 skids.

gg

 

[stee6043]

Are you guys 100% comfortable using treated lumber as a long term support for something with rigid plumbing connections? Personally, I've seen lumber dry, crack, shrink, etc. I wouldn't want to use lumber to support my tank (even though it certainly should be strong enough). My install is meant to be a 30 year gig. I'm not saying it won't work. I'm just wondering what others think....

 

[ewdudley]

Are you guys 100% comfortable using treated lumber as a long term support for something with rigid plumbing connections? Personally, I've seen lumber dry, crack, shrink, etc. I wouldn't want to use lumber to support my tank (even though it certainly should be strong enough). My install is meant to be a 30 year gig. I'm not saying it won't work. I'm just wondering what others think....

I think wood is very strong, resilient, durable, and stable. Just look at some of the superstructures that have been supporting massive tile roofs for centuries in Europe. I wouldn't be surprised if a lot of it has seen many stints above 60 degC in the summer in Rome.

And a couple thousand liters of water in a 5 mm thick tank doesn't amount to much weight at all when it's supported by wood.

http://2.bp.blogspot.com/__UhNdGEO9cU/TGxcdbTjHQI/AAAAAAAAAFM/edcuIcFt24Y/s1600/100_0681.jpg

--ewd

 

[goosegunner]

Are you guys 100% comfortable using treated lumber as a long term support for something with rigid plumbing connections? Personally, I've seen lumber dry, crack, shrink, etc. I wouldn't want to use lumber to support my tank (even though it certainly should be strong enough). My install is meant to be a 30 year gig. I'm not saying it won't work. I'm just wondering what others think....

I guess I could come up with something different, not sure what. I could buy some pallet rack but my space is about 5 1/2 feet wide where the tank is.


I could use metal strapping to hold together boards if they would crack. Like a band.

gg

 

[goosegunner]

Are you guys 100% comfortable using treated lumber as a long term support for something with rigid plumbing connections? Personally, I've seen lumber dry, crack, shrink, etc. I wouldn't want to use lumber to support my tank (even though it certainly should be strong enough). My install is meant to be a 30 year gig. I'm not saying it won't work. I'm just wondering what others think....

I think wood is very strong, resilient, durable, and stable. Just look at some of the superstructures that have been supporting massive tile roofs for centuries in Europe. I wouldn't be surprised if a lot of it has seen many stints above 60 degC in the summer in Rome.

And a couple thousand liters of water in a 5 mm thick tank doesn't amount to much weight at all when it's supported by wood.

http://2.bp.blogspot.com/__UhNdGEO9cU/TGxcdbTjHQI/AAAAAAAAAFM/edcuIcFt24Y/s1600/100_0681.jpg

--ewd

Did you prime or paint your tanks after install?

Is it needed?

gg

 

[ewdudley]

Did you prime or paint your tanks after install?

Is it needed?

gg

I was surely tempted to prep and paint them.

But for as long and hard as I thought about it I could not come up with any purpose painting would serve, except possibly to prevent buildup of afraidium.

--ewd

 

[DaveBP]

During my year as a geology major living near and studying the San Andreas fault in California I developed a rather severe sensitivity to the seismic portion of the afraidium spectrum. Seeing a house with only minor damage to the tile inside laying sheared off its foundation by 18" inches gave me a kind of PTSD.

Anything anchoring those tanks to the wall other than the plumbing, Eliot?

 

[btuser]

Did you prime or paint your tanks after install?

Is it needed?

gg

I was surely tempted to prep and paint them.

But for as long and hard as I thought about it I could not come up with any purpose painting would serve, except possibly to prevent buildup of afraidium.

--ewd

Ok, I just spit my soup out. (LOL)

 

[ewdudley]

During my year as a geology major living near and studying the San Andreas fault in California I developed a rather severe sensitivity to the seismic portion of the afraidium spectrum. Seeing a house with only minor damage to the tile inside laying sheared off its foundation by 18" inches gave me a kind of PTSD.

Anything anchoring those tanks to the wall other than the plumbing, Eliot?

The top manifold connects to half couplings welded to the apexes of the tanks, same as the bottom in the photo, and it comes up to within three inches of the bottom of the trusses above. So I just screwed pieces of 2x10 on either side of the manifold on each of four available perpendicular trusses. My theory is that if the trusses come down, tumbling tanks would be just another facet of a full-fledged catastrophe. Plus here we have the luxury of some pretty long odds when it comes to seismic risk.

Oh, and on the original topic, that's 3" high-density 70 psi foam in the photo. Counting just the four 1.5"x6" pieces for each tank and disregarding any load-spreading by the plywood, it works out to 25 psi or so. I got the tanks into position and got a few reference measurements after a week or so with the tanks empty, then filled the tanks and found maybe 25 thousandths of an inch compression. A couple months later nothing had moved so I buttoned it up and called it good.

--ewd

 

[DaveBP]

Yeah, I'm getting pretty complacent myself. Once in a while I look over at my vertical well tank and think it looks naked not bolted to the concrete wall with a minimum 16ga. strap and bolts (code in coastal California).