Hi all! I'm glad I found this forum, I've been bugging people on my aquarium forum about the same issue.
I have a 180 gallon aquarium which is now sitting in the garage slowly angering my wife. I want to reinforce the floor where it will sit (the tank, empty is almost 400 lbs. Add water and we hit close to 2000 lbs!)
So after some discussion about sistering the current 2x8 joists (10 foot span from foundation wall to beam) on 16 inch centers, and discussing the need to notch the sisters due to willy-nilly piping/wiring, I've decided the "simplest" solution is to just put in a beam to make the span 5', if not 4' where the tank will sit.
So now i'm looking at a 8' 4x8 (8 feet because the tank is 6 feet long) beam supported by two 4x4 posts probably spaced 6" apart so that the beam will overhand about a foot on each side. I might use a 10' piece, but that doesn't fit in my minivan
The crawlspace is not exactly level (the house is on a hill and the "floor" follows that), and it has rat proofing on it. I don't know how thick the rat proofing (concrete) is, I'm estimating 2 to 3 inches.
So my plan is this;
- Cut out two squares, 16"x 16" which are centered 6 feet part for the footings
- Dig a 16x16 square 12 inches deep for a concrete footing
- pour 2 inches of concrete in each hole
- drop in either two pieces of rebar in the shape of an X, or 4 pieces in the shape of a square (do I even need to do this?)
- Fill up the rest of the hole
- Set a preformed concrete pier (sort of like the Dek-Blocks that you use for free floating deck footings) into the concrete. The pier has metal straps preattached to it.
- Wait for the concrete to harden. I may or may not wait 28 days for it to reach max strength.
- Somehow attach the beam to the joists (simpson metal thingies probably)
- Cut and then fit 4x4 posts under the beam and onto the preformed pier.
- Attach posts to pier with the straps, and attach posts to beam.
Now the questions;
1) The ground is somewhat damp, because I'm on a hill and there is always moisture. I'm assuming that under the house that is the same. The soil is very claylike (from the gardening I've done). This is why I want to pour a concrete footing instead of just placing the pre-formed pier on the ground after cutting away the weak rat proofing. But, do I need a 12 inch deep footing? I'm sure that 12 inches verses 10 or 8 is not going to make much of a difference in terms of labour (me, digging out a few more inches) and a touch more concrete, which is cheap.
2) Do I need the rebar on the bottom? I know it has to be at least 2 inches from the outer edges. X or square?
3) Should I forget the pre-formed pier and just set the post on the poured footing? Or embed an anchor for a metal post foot? It would be a bit cheaper. I was thinking of the pre-formed pier because the other main beam has piers that look similar (posts on a pyramid like pier)
4) I'll be using an SDS rotary hammer to cut out the squares. Or rather I'll drill some holes at the corners and then "perforate" the concrete and then connect the dots with a chisel (or the SDS chisel bit). I don't want to mess up my circular saw or the crawlspace with the dust that will be created by the cut. Is there a better way?
5) Do I have to do something to prevent expansion problems between the poured concrete and the current rat proofing? Like how sidewalks have that fuzzy stuff in the expansion joints? Or can I just pour the concrete and forget about those details?
I know, a lot of questions, but hey, maybe I'll get a lot of answers!
Thanks guys!
Vince
I have a 180 gallon aquarium which is now sitting in the garage slowly angering my wife. I want to reinforce the floor where it will sit (the tank, empty is almost 400 lbs. Add water and we hit close to 2000 lbs!)
So after some discussion about sistering the current 2x8 joists (10 foot span from foundation wall to beam) on 16 inch centers, and discussing the need to notch the sisters due to willy-nilly piping/wiring, I've decided the "simplest" solution is to just put in a beam to make the span 5', if not 4' where the tank will sit.
So now i'm looking at a 8' 4x8 (8 feet because the tank is 6 feet long) beam supported by two 4x4 posts probably spaced 6" apart so that the beam will overhand about a foot on each side. I might use a 10' piece, but that doesn't fit in my minivan
The crawlspace is not exactly level (the house is on a hill and the "floor" follows that), and it has rat proofing on it. I don't know how thick the rat proofing (concrete) is, I'm estimating 2 to 3 inches.
So my plan is this;
- Cut out two squares, 16"x 16" which are centered 6 feet part for the footings
- Dig a 16x16 square 12 inches deep for a concrete footing
- pour 2 inches of concrete in each hole
- drop in either two pieces of rebar in the shape of an X, or 4 pieces in the shape of a square (do I even need to do this?)
- Fill up the rest of the hole
- Set a preformed concrete pier (sort of like the Dek-Blocks that you use for free floating deck footings) into the concrete. The pier has metal straps preattached to it.
- Wait for the concrete to harden. I may or may not wait 28 days for it to reach max strength.
- Somehow attach the beam to the joists (simpson metal thingies probably)
- Cut and then fit 4x4 posts under the beam and onto the preformed pier.
- Attach posts to pier with the straps, and attach posts to beam.
Now the questions;
1) The ground is somewhat damp, because I'm on a hill and there is always moisture. I'm assuming that under the house that is the same. The soil is very claylike (from the gardening I've done). This is why I want to pour a concrete footing instead of just placing the pre-formed pier on the ground after cutting away the weak rat proofing. But, do I need a 12 inch deep footing? I'm sure that 12 inches verses 10 or 8 is not going to make much of a difference in terms of labour (me, digging out a few more inches) and a touch more concrete, which is cheap.
2) Do I need the rebar on the bottom? I know it has to be at least 2 inches from the outer edges. X or square?
3) Should I forget the pre-formed pier and just set the post on the poured footing? Or embed an anchor for a metal post foot? It would be a bit cheaper. I was thinking of the pre-formed pier because the other main beam has piers that look similar (posts on a pyramid like pier)
4) I'll be using an SDS rotary hammer to cut out the squares. Or rather I'll drill some holes at the corners and then "perforate" the concrete and then connect the dots with a chisel (or the SDS chisel bit). I don't want to mess up my circular saw or the crawlspace with the dust that will be created by the cut. Is there a better way?
5) Do I have to do something to prevent expansion problems between the poured concrete and the current rat proofing? Like how sidewalks have that fuzzy stuff in the expansion joints? Or can I just pour the concrete and forget about those details?
I know, a lot of questions, but hey, maybe I'll get a lot of answers!
Thanks guys!
Vince