Structural Engineer

[ezrk]

Anyone know or have used a structural engineer for aquarium purposes?

We are going to move in the next couple of months and that means leaving behind our slab floor condo. We want to locate at least one large tank in the main living area which is not a slab and would like to see what is safe and what support options exist.

 

[Tony]

One guy that we used to use at work was Eric Rathgeber. Never talked to him about residential construction, but they could probably point you in the right direction. Their website is http://www.rath-goss.com/. It may be sort of expensive though. Their billing rates are generally over $125-$150/hr.

Have you guys picked a place? If so, make a quick sketch (with load-bearing walls and direction of joists) and I'll take a look at it. I can't guarantee anything, but could at least point you in the right direction.

 

[ezrk]

Have you guys picked a place? If so, make a quick sketch (with load-bearing walls and direction of joists) and I'll take a look at it. I can't guarantee anything, but could at least point you in the right direction.

We have a place, but don't own it yet. We can probably get some basics early next week when we go for a home inspection. My guess is that it is ok for some things, but we have to decide where to put our pair of 110s plus sumps which are likely to be problematic.

 

[WendyFish]

Thanks Tony! We will have a diagram on Monday. Might be a minor challenge figuring out the joists, as all the areas are finished. The obvious direction would be in our favor for what we want to do, given that length wise through the house would be MUCH longer run than width wise -- but who knows what they were thinking in the 70s.

We are perfectly likely to bring in a GC because there are a few other things we probably want to do -- would they have a handle on something like this, or should we be looking for a specialist like Eric?

 

[halak]

When I moved, I asked the home inspector who told me that it was definitely okay to put my 125 upstairs and even along the beams. I did it (along the beams) and have had no problems (I have no sump underneath). It is a standard 125 (6' long). My house was built in 1972. If I were you, since your tanks weigh more per square inch than mine, I would ask the home inspector first and see is s/he can recommend an expert if s/he is not sure. After all, you are already paying for the inspection.

 

[WendyFish]

Thanks for your thoughts Viktor! We are actually thinking of putting a 125 on that floor and maybe not the sumped 110s. Kind of thinking a tank like that doesn't weigh too much more than a big bookshelf, and you wouldn't think twice about that.

We'll see what the inspector thinks!

 

[zackcrack00]

Congratulations on the move! Hope it's exiting? What are sumps???

 

[scientist0724]

Are you guys moving out of Reston?

Arlene

 

[ezrk]

Are you guys moving out of Reston?

Arlene

Actually we are staying in Reston, though we looked at everything from Reston to into the District. We are buying a townhouse about a quarter mile from the new Wiehle metro stop which is the closest we could get to a metro station.

We are most likely going to change our existing 55 into a 125 and put that on the main floor and pretty much everyone thinks that should be fine. That said we would like to know what are options are...

 

[Tony]

Good stuff, guys. Congrats on the house!

Generally speaking, the main beam in the house runs in the long direction (parallel to the front of the house), down the middle of the span between the front and back foundation walls. Joists run off of this and span between the beam and the front and back walls. I believe that the demising walls between units in town homes are generally CMU (for fire rating), so you can consider them to be as sound as concrete in terms of supporting a fish tank up against that wall.

So either putting the tank parallel to the front of the house or along an exterior wall (perpendicular to the front) is favorable.

I like what Viktor suggested... have the home inspector or contractor take a look at it. Having a commercial engineer may be overkill, but some appreciate it for the peace of mind it carries. On the other hand, if your contractor is not able to make a decision, he can probably recommend someone cheaper that a big firm like the one I mentioned. Worst case scenario, you put the tank on a divider or exterior wall (if you are on an end unit) and throw a bottle jack under the front of the tank, with some blocking under the joists.

 

[scientist0724]

Actually we are staying in Reston, though we looked at everything from Reston to into the District. We are buying a townhouse about a quarter mile from the new Wiehle metro stop which is the closest we could get to a metro station.

We are most likely going to change our existing 55 into a 125 and put that on the main floor and pretty much everyone thinks that should be fine. That said we would like to know what are options are...

Very cool guys! I see a house warming party in the near future!!! :lol:

Arlene

 

[YSS]

I have my 265G (7 foot) on the main floor. The wall behind the tank is supported by a steel beam below, but I did not need additional support for the floor. The tank is placed perpendicular to the joists.

 

[ezrk]

Good stuff, guys. Congrats on the house!

Generally speaking, the main beam in the house runs in the long direction (parallel to the front of the house), down the middle of the span between the front and back foundation walls. Joists run off of this and span between the beam and the front and back walls. I believe that the demising walls between units in town homes are generally CMU (for fire rating), so you can consider them to be as sound as concrete in terms of supporting a fish tank up against that wall.

So either putting the tank parallel to the front of the house or along an exterior wall (perpendicular to the front) is favorable.

We are not an end unit, the walls separating units in our town houses are (probably) brick, they are least brick on the exterior. All floors of the townhouse are basically divided into quarters and I believe the structural walls are on those quarter lines, there are basically no other walls in the unit other than closet partitions.

We would be putting the 125 on the demising wall separating units. If the joists are running perpendicular to the demising wall then we should be good. If they run paralell to the demising wall we might have an issue as there is no good place to put a tank on the front or back wall of the unit.

 

[Tony]

We are not an end unit, the walls separating units in our town houses are (probably) brick, they are least brick on the exterior. All floors of the townhouse are basically divided into quarters and I believe the structural walls are on those quarter lines, there are basically no other walls in the unit other than closet partitions.

We would be putting the 125 on the demising wall separating units. If the joists are running perpendicular to the demising wall then we should be good. If they run paralell to the demising wall we might have an issue as there is no good place to put a tank on the front or back wall of the unit.

Gotcha. Do you have drop ceilings in the basement? It'd make checking the direction of the joists a lot easier.

 

[ezrk]

Gotcha. Do you have drop ceilings in the basement? It'd make checking the direction of the joists a lot easier.

Unfortunately not. The basement is a fully finished (as it is in many townhouses) so full 8 foot drywall ceilings. We are going for the home inspection tomorrow so will poke around a bit. Otherwise we are waiting until we take possession to cut a hole in the basement ceiling...

 

[WendyFish]

After the inspection today, it seems like good news! The joists do run perpendicular to where we'd want to put the tank, against the joining wall which is indeed brick. The inspector agreed that a tank of that size would be fine; noted we could do a couple of easy things to put our minds at ease as well. We are going to put in hardwood flooring anyway, which he suggested would help some; and we could put a solid sheet of plywood under the tank to distribute it even further. The "medium" intensity step is something we could do because we are going to redo the floors -- as long as the flooring guys are in there, they could pull up the subfloor and reinforce the joists. This would probably let us even contemplate putting one of our current tanks up there if we wanted to.

 

[Tony]

Good to hear, Wendy.

When are you guys thinking of moving?

 

[ezrk]

Good to hear, Wendy.

When are you guys thinking of moving?

Probably August. Also the joists are not dimensional lumber, but truss joists (or something like that). So apparently are easy to reinforce by adding more plywood.

 

[ezrk]

Just an update for a topic that is always of interest.

It turns out our new townhouse is a bit unusual. It does not have conventional joists, instead the floor(s) are supported by 2x4 trusses that are 24" on center. This let's them span the entire 22' width of the townhouse with no structural support in between, so there are (excepting around the stairwell) no structural walls in the interior of the townhouse.

Anyway, the engineer does think we should reinforce the floors/trusses. We are waiting to get back the exact "recipe" but he indicated that screwing and gluing a few feet of plywood onto each truss to stiffen (essentially sistering the trusses) them would be the (likely) recommendation.

Our move is delayed a bit by other work as the hardwood floors are going to be a bit slow to arrive, we probably won't fully move until September.