First big tank, wondering about floor support?

unfeazi · 08/24/2016, 08:11 PM

I am beginning to plan my first build thats of a decent size. The system will be about 150 gallons total (110 DT and ~40 sump) and was wondering if I need to worry at all about the floor as the tank will be sitting above a crawl space. Ive attached pictures below. The tank would sit parallel with the 2x6's that are 16" apart. There are two other joists that run perpendicular to the 2x6's which are 4x6's and are about 8' apart. The tank would be placed against the wall shown in picture 3 which is an outside wall to the house.
image1.jpg

image2.jpg

image3.jpg

Kevin Guthrie · 08/24/2016, 09:34 PM

I don't understand where in the pic the wall is. If the whole tank is on a single 2x6, that is not good. Can you run a couple of parallel 2x6s across the same span?

Your total weight will be a ton - 190 x 8 for water, plus the hard stuff.

unfeazi · 08/24/2016, 09:59 PM

Sorry, the wall is on the top part of the picture (the cement with the grate over the hole). You think it would be best to run two more 2x6's in parallel to the one that is already in place? That would make the tank run across a total of 3 2x6. When adding the 2x6, I was thinking of getting premade cement piers (similar to the ones in picture 2) and then using 4x4 and metal braces to hold them up. Would this be sufficient?

checha32 · 08/26/2016, 04:25 PM

I would highly recommend that you consult with a contractor before you proceed. This will help you avoid a costly repair in a worst case scenario.

Sent from my SM-G935V using Tapatalk

ColoReefer970 · 08/26/2016, 06:18 PM

Get 5 friends about 200 pounds each, get close together...almost hugging....if you can all stand there you're fine eh? then jump up and down if you're worried still....if it feels iffy, do something supportive

davocean · 08/26/2016, 07:58 PM

Are you sure those joists are 2x6 and not 2x8?
It kind of looks like 2x8's to me, if those 4x6's are upright and just eyeballing it, and 2x8 is much more common for floor joists (I am a Contractor/carpenter)
Also I see you already have some vertical support posts that should really help you.
Generally speaking as long as your framing is sound I would not see a 150g as an issue.

As to the comment of friends all group hugging, that is not quite the same as a dead load that will be sitting long term, and it's not that I don't trust framing to hold that tank weight, you just don't want those joists to sag over time, that is the issue we typically try to avoid.

Reel North · 08/26/2016, 08:54 PM

What Dave said.

Definitely consult with a professional, and if need be, run some beams underneath your joists. This will provide additional structural support.

A ton really isn't a lot of weight on 2x8, but on 2x6 it sure is.

Desert Sea · 08/26/2016, 09:12 PM

I agree with daveocean about the joist size. (I am also a Building Contractor, carpenter by trade) Base on the pictures you attached, your foundation is cast in place concrete and looks fairly new, meaning it wasn't poured in 1950. 2x6s don't meet code for floor joists so my guess is that they are 2x8s. Have you measured them?

A floor framed in 2x6s would have a lot of bounce to it when you walk across it. I would not recommend setting up a 150g tank on a floor framed out of 2x6s. The floor would not immediately fail but the long term deflection from the tank weight would cause problems. And then you have to account for any live load added to it. I would recommend you consult with a knowledgeable framing contractor or structural engineer.

Here is a link to a good article by a structural engineer regarding floor loads from aquariums.

http://badmanstropicalfish.com/articles/article28.html

Grayhead · 08/27/2016, 08:37 AM

I am a general contractor as well. Here's my recommendation. Locate the exact spot of the tank. You will need to know the location of the corners of the tank. That will be the most crucial locations for supports your tank. Go to a lumberyard (not Lowe's or home depot) and purchase laminated beams the same thickness as your floor joist. They are engineered to carry more load the standard dimensional lumber. Run these beams from girder support to girder support.
When I did my support for my 240, I added footing under the 4 corners of the tank as well as the 2 locations that landed on the girder system. If you actually have 2x6 floor joist, then double the lam beams.
I would also highly recommend contacting a professional to assess what you are doing before loading that area down with 2000lb of load. It may look fine initially, but over time, things can deflect. We all know what happens if the tank is not properly supported.

08/24/2016, 08:11 PM	#1
unfeazi Registered Member Join Date: May 2013 Posts: 140	First big tank, wondering about floor support? I am beginning to plan my first build thats of a decent size. The system will be about 150 gallons total (110 DT and ~40 sump) and was wondering if I need to worry at all about the floor as the tank will be sitting above a crawl space. Ive attached pictures below. The tank would sit parallel with the 2x6's that are 16" apart. There are two other joists that run perpendicular to the 2x6's which are 4x6's and are about 8' apart. The tank would be placed against the wall shown in picture 3 which is an outside wall to the house. image1.jpg image2.jpg image3.jpg

08/26/2016, 07:58 PM	#6
davocean Registered Member Join Date: Nov 2005 Location: San Diego, CA Posts: 14,655	Are you sure those joists are 2x6 and not 2x8? It kind of looks like 2x8's to me, if those 4x6's are upright and just eyeballing it, and 2x8 is much more common for floor joists (I am a Contractor/carpenter) Also I see you already have some vertical support posts that should really help you. Generally speaking as long as your framing is sound I would not see a 150g as an issue. As to the comment of friends all group hugging, that is not quite the same as a dead load that will be sitting long term, and it's not that I don't trust framing to hold that tank weight, you just don't want those joists to sag over time, that is the issue we typically try to avoid. __________________ There's a fine line between owning your tank and your tank owning you! Current Tank Info: SCA 120g RR Starfire, Tunze silence 1073.02 return, 40g sump w/ fuge, SWC Extreme 160 cone skimmer,Geismann reflexx 4xT5, 2x Panorama Pro LED strips, Vortech MP40QD

08/26/2016, 08:54 PM	#7
Reel North New King of Quarantine Join Date: Apr 2010 Location: Hammertown, Canada eh Posts: 1,175	What Dave said. Definitely consult with a professional, and if need be, run some beams underneath your joists. This will provide additional structural support. A ton really isn't a lot of weight on 2x8, but on 2x6 it sure is. __________________ It takes a very rich man to buy cheap things Current Tank Info: frag tank. Lame

08/24/2016, 09:34 PM	#2
Kevin Guthrie Registered Member Join Date: May 2013 Posts: 506	I don't understand where in the pic the wall is. If the whole tank is on a single 2x6, that is not good. Can you run a couple of parallel 2x6s across the same span? Your total weight will be a ton - 190 x 8 for water, plus the hard stuff.

08/24/2016, 09:59 PM	#3
unfeazi Registered Member Join Date: May 2013 Posts: 140	Sorry, the wall is on the top part of the picture (the cement with the grate over the hole). You think it would be best to run two more 2x6's in parallel to the one that is already in place? That would make the tank run across a total of 3 2x6. When adding the 2x6, I was thinking of getting premade cement piers (similar to the ones in picture 2) and then using 4x4 and metal braces to hold them up. Would this be sufficient?

08/26/2016, 04:25 PM	#4
checha32 Registered Member Join Date: Mar 2009 Posts: 1	I would highly recommend that you consult with a contractor before you proceed. This will help you avoid a costly repair in a worst case scenario. Sent from my SM-G935V using Tapatalk

08/26/2016, 06:18 PM	#5
ColoReefer970 Registered Member Join Date: Jun 2016 Location: Earth Posts: 88	Get 5 friends about 200 pounds each, get close together...almost hugging....if you can all stand there you're fine eh? then jump up and down if you're worried still....if it feels iffy, do something supportive

08/26/2016, 09:12 PM	#8
Desert Sea Registered Member Join Date: Mar 2016 Posts: 294	I agree with daveocean about the joist size. (I am also a Building Contractor, carpenter by trade) Base on the pictures you attached, your foundation is cast in place concrete and looks fairly new, meaning it wasn't poured in 1950. 2x6s don't meet code for floor joists so my guess is that they are 2x8s. Have you measured them? A floor framed in 2x6s would have a lot of bounce to it when you walk across it. I would not recommend setting up a 150g tank on a floor framed out of 2x6s. The floor would not immediately fail but the long term deflection from the tank weight would cause problems. And then you have to account for any live load added to it. I would recommend you consult with a knowledgeable framing contractor or structural engineer. Here is a link to a good article by a structural engineer regarding floor loads from aquariums. http://badmanstropicalfish.com/articles/article28.html

08/27/2016, 08:37 AM	#9
Grayhead Registered Member Join Date: Oct 2011 Posts: 581	I am a general contractor as well. Here's my recommendation. Locate the exact spot of the tank. You will need to know the location of the corners of the tank. That will be the most crucial locations for supports your tank. Go to a lumberyard (not Lowe's or home depot) and purchase laminated beams the same thickness as your floor joist. They are engineered to carry more load the standard dimensional lumber. Run these beams from girder support to girder support. When I did my support for my 240, I added footing under the 4 corners of the tank as well as the 2 locations that landed on the girder system. If you actually have 2x6 floor joist, then double the lam beams. I would also highly recommend contacting a professional to assess what you are doing before loading that area down with 2000lb of load. It may look fine initially, but over time, things can deflect. We all know what happens if the tank is not properly supported.