Underground Storage

[tom in maine]

Just to clarify the difference between DIY foam kits and contractor systems:
DIY kits are nitrogen pressurized tanks of the two chemicals that make the foam.
These are susceptible to temperature differences which make the feed rates of the two chemicals vary.
This either yields brittle foam on one extreme to gummy foam on the other extreme.
The results are not always consistent and the whole system is going to yield different mixes as the project goes on.

A contractor will use heated tanks, heated hoses and a pumped system system that accurately meters out the right mix of chemicals.
A contractor can screw up the mix, but I can tell you that the results from someone who does it right is significantly better.
And they can deliver mixes that might stand up a lot better than any DIY foamed project.

I have done a lot of DIY installations in many different situations. None of them compared to contractor installs.
In a previous life, I had worked with a DIY foam company to develop new products. The product is nice for small applications, but they ain't cheap and
a contractor should be able to deliver better foam for the same cost. It also has a shelf life. The isocyanurate can pick up moisture and not flow right if it sits too long.

It is fun to do, but maybe you can get a contractor who is doing the job to let you use his gear for a couple minutes. Then you have
bragging rights and a great job, for the same cost per board foot.

 

[powerspec]

Now that sounds like good advice to me. The Froth Paks are way too expensive and the quality is uncertain.

 

[pgarch]

Can an underground tank be non presurized?

 

[Gooserider]

Can an underground tank be non presurized?

No reason it can't be... However as mentioned by many people in lots of threads, underground tanks tend to be problematic - unless extreme care is taken in their install they will tend to have high thermal losses, not to mention the potential issues w/ servicing them, etc...

I would tend to say that in general, while one can do an underground tank, and many have, it is best to think of such tanks as "last resort" approaches, and only go underground if you can't find a different method that works.

Gooserider

 

[Nofossil]

I'd be very concerned with safety with an unpressurized underground tank. Most unpressurized tanks have a cover over the top. If that cover degraded with time, moisture, and temperature you could eventually have a failure. Falling into a tank at 180 °F would be fatal in a particularly brutal fashion.

 

[Gooserider]

I'd be very concerned with safety with an unpressurized underground tank. Most unpressurized tanks have a cover over the top. If that cover degraded with time, moisture, and temperature you could eventually have a failure. Falling into a tank at 180 °F would be fatal in a particularly brutal fashion.

True, and a very good point that I hadn't thought about... However I would still say that as long as proper design was done, and the cover was properly built for strength and durability, etc. then it should still be possible to do such a tank, though I would advise against it for the reasons mentioned already. Just add this warning to the list...

Gooserider

 

[emesine]

If you want to do an underground storage tank, I think you are asking for trouble insulating the outside. You'll never keep it dry. Why not put in a 2-3000 gallon cement cistern? You can line the inside with foam board, then put in a liner. Cisterns are watertight, so water leaking in shouldn't be much of an issue, and most bugs are not equipped with concrete drilling tools. The heat of the water will drive out any moisture that seeps in. I am doing one now as part of my basement.

Andrew

 

[timberr]

I think this all boils down to a simple concept. We use wood to heat water, we all work hard to secure our wood supply. We diligently light our fire's when necessary to heat our storage so we can then relax until the next fire is needed. My question is, storage will ALWAYS loose btu's to the surrounding environment, this is a law of physics, would you rather lose those BTU's to the inside of your house or to the outside environment? I like mine in the house thank you.

I like the cistern idea, my neighbor has a 1,200 gal. cistern in his basement. He built his house in 1992 with the cistern and has been gassifying since then.