Concrete slab load limits.

[warhammer]

Why such a big tank?

Warhammer

Thanks. That is an interesting site, and I added it to my bookmarks, unfortunatly in about 90 minutes looking thru it, I didn't find what I was looking for.

Perhaps if I lay out the details of the project I am contemplating. I want to add a large super insulated hot water storage tank to an upcomming home build. When I say large, I am talking 750 gallons. That is a tank approximatly 70" in diameter by 45" tall. A tank this size will have a bottom surface area of around 26.73 SQ/FT and the bottom insulated pad will have a surface area of approx 36.67 SQ/FT. At around 6400# all up tank weight when full, that is a load of 174-239 LB per SQ/FT, depending on how much the lower insulation distributes the load over the floor. I am estimating that the The ground floor/basement level will be a 4" re-enforced slab with footings over 2-4" of insulation, with ICF walls. With the potential load and footprint from the tank described above, does anyone think the area this tank will occupy will require any additional floor thickness? Is there a "rule of thumb" that says in general, do not exceed XXX# per SQ/FT on a 4" slab.

Thanks

 

[RonMar]

Why such a big tank?

Warhammer

My goal for this new house is to meet the majority of it's heat needs with solar. 750 gallons of water working between 90 and 150 F, can store around 370KBTU in that 6200# of water. With the tank at 150F, and an average heat load of 10KBTU, that is 37 hours of heat. A 15KBTU load would deplete the tank in 24 hours We get quite a bit of winter sun, but it can also be clouded for days at a time. The planned large storage, and a planned large collector area as well as a 10' tracking parabolic collector, will hopefully store enough heat on sunny days to carry me over the shorter clouded periods and reduce the ammount of fuel and electric I need to provide.

I burn a lot of branch and blowdown waste off my property each year. I also only have about 30% of my property the way I want it and there is a LOT of cleanup to do in the future. That burnable waste is going to be chipped and saved for the winter months to fire a small outside boiler(pellet stove on steroids). With the available storage tank, this boiler should only have to be lit-off occasionally, and will not have to run all the time during extended clouded periods. The large tank gives me some flexibility in how I can manage my heating system.