Hi all, I am currently in the process of renovating a split level home. On the first floor we will be adding a second floor and wanted to do open floor concept (remove wall between kitchen/dining and living) on the first floor. The beam is to span 24 feet and we didn’t want a post if possible. House is framed with 2x4s, roof rafters 2×8 and the new floor joists will be 2×10. I hired an architect to spec out the beam for us. We wanted the beam to be flush and since we are using 2×10’s that gave us 9-1/4. The architect came back with 4 microlams lvls (9.5-in x 1.75-in x 24-ft). I asked him for the load calculations and basically got back the “passed” sheet from the weyhauser forteweb calculation. Is this typically what architects give you when you ask for their calculations? We also got a stamped drawing to show the city but that just had the beam in the drawing.
I had another architect run preliminary numbers for me a months ago and he came back with three lams of 1-3/4 x 22 x 24′ which seems like a big difference.
The other question I had was about the lumber yard. I have read in a few spots that typically the lumber yard will review the loads and beam info but I have no experience here. Would a lumber yard also run the load calculations?
Thoughts?
Replies
Here in NW Oh. a quality lumberyard will send drawings of existing dimensions and construction to a beam supplier. Their engineering dept will run the calcs and supply drawings of what is needed to complete the job. Most city/county bldg dpts will accept these.
Calvin thanks for the info. I wonder if this is usually the case with 24' microlams since most yards have them in-stock by us. I stopped by one of the yards today and mentioned if they ran the calculations and the guy said no but I would have to show him a drawing. I'll call a few other places and report back.
They may not run calculations but they should be able to call the MFG and the MFG will normally give input as described. Some people take what you say VERY LITERALLY so often you have to re-frame your question to get to the real answer.
Do you run calcs? No we don't run any calcs here. Likely a true statement.
Can we check the MFG website/customer service to see if they will help us size this right???????
Clovis,
You can buy anything a yard has for sale.
But
What do you need?
That’s the question I attempted to answer. A yard will send your drawing showing existing conditions and what you want to hold up to an LVL or glue lam supplier and they will do the calculations.......send back to the yard what you need to support the load and what else you need to hold up that beam (post locations and bearing points, header sizes etc....
Or
Call an engineer and pay them to do it.
End result, you’ll submit their drawings to bldg inspection for approval.
this PDF may help...
Forte is a web-based application, so you can go in and play with the numbers yourself. But be careful - if you don't know what the various terms mean or what to input, you're likely to miss something. Anyone can use it, but not everyone can use it correctly. Quick tip, for what it's worth: don't forget to input your tributary width.
Yes, the Passed Report from Forte, or Boise Cascade, or any other manufacturer's software when backed by the architect's or engineer's stamp/signature is what building officials accept. I provide these for my clients' submittals as part of the gravitational loading. Engineers like receiving them as the basis for their lateral load calcs. Lateral in C+ zones often increases the beam one size and the bearing connection details.
22" deep beams vs 9.25" deep beams will always be a big difference. Depth rules! But a 3 ply vs 4 ply in this scenario means the short one of these is highly stressed or the deep one is over-designed.
Can you post the forte printout here? I am doubtful that a (4)9.5" LVL can span 24' , even if lightly loaded. I do not know what kind of tributary width you are trying to support, but it is not going to hold much..
On another note, why on earth would you pay an architect (or 2) to size a beam?? Many architects I know would have to think hard before telling you the dimensions of a (3)2x10, let alone what it could span...You should be looking to an engineer, not an architect, for structural items like this.
I have seen some really bad stuff (both grossly oversized and grossly undersized members) out of lumber yards running third party software too.. Some do a great job, others not so much. Even the good ones will struggle with atypical conditions and complex loading.
Thanks for all the replies fella's, learning as I go. I went to get quotes from a few lumber supplies and asked them if they ran the beam calculations with the manufactures. One didn't and two others did. One of the supply places already got back to me and their engineers said there was "no load applied" to the beam and then they suggested a 7 x 20 5/8 Glulam etc. I am little upset by the whole situation. I relayed the issue with the beam calc to the architect and he said he must have forgot something in the software. He said its web based now and its difficult to print out the beam options. Obviously, you can imagine how I am feeling right around now.
@rww0002 I actually was going to use an engineer to do the job but I was also going to need an architect for a porch and garage variance in a few months. The engineer was cheaper but figured if the architect said it was in his wheel house, it wouldn't be a problem. You make some good points. I also agree and know manufacturers want to sell product at the end of the day so if they can over size I am sure they will.
Let me know if the jpeg is readable. I had to download it as it wasn't showing up in the popup window
Looking over the attached, it looks like they are only carrying 2' width of floor on this beam (80 plf Live Load = 40 psf x 2' - similar for Dead Load). I am not sure what your joist spans are framing in to this, or whether there are beams coming in to each side, but this is likely woefully inadequate.
The tributary width and loading of the beam is the most basic of input and ultimately the most important. Anyone who misses this by much and does not catch it does not need to be sizing beams, and definitely does not need to be stamping structural designs! It should have been a red flag to the designer anyway since the span to depth ratio of the member is way out of the expected range. If you paid for a stamped design that was to include this member I would request that the architect pay an engineer to size this member correctly. I do not know your specifics, but you should be expecting a member in the ±16" depth range, maybe deeper and either a 3 or 4 ply. Have this member sized by someone who knows what they are doing, not by some Joe with access to software they may not completely understand. If a designer cannot do the calculation by hand (and know the background of the design checks) they should not be using software to do it for them. Trash in = trash out.
RWW0002 its a little perplexing that this slipped by him honestly. I am up on the fence on what to do at this point. Still waiting to hear back about the beam (2 days later). Still can't wrap my head around why he mentioned printing the load cal sheet via forge was a problem. Unless of course now the software makes you pay for the calculations.
Go with glulam. Typically less expensive, similar in final size, and you can design out the deflection by adding in camber. The contractor must be able to read "TOP" and put that side up of course. This will help level out the ceiling since the deflection of this main beam will be in addition to the deflection of the intersecting joists and beams.
The architect originally mentioned a parallam beam which is way stronger then a microllam. I will be installing the beam with my guys. Since we don't know what the beam will weight I am still in waiting for the specs. Microllams are usually stocked at the yard but assume glulams or parallams will take turn around time.
Paralam are not much stronger than LVL, and they will have almost identical deflection (which will control for a long shallow beam).
I am not sure if by glulam you are talking about a paralam product, or traditional glulam beams made up of flatwise plys of solid lumber, but either way a 9 1/2" beam is not going to span 24'. Period. Even if you camber it, it will bounce all over the place. No magic product is going to make that span with wood. Even with a steel beam you might be hard-pressed to make the depth work.
I would not trust this Arch to size the beam, even if it means eating the fee you already paid them. Anything other than "you know what you are right I can't believe I messed that up, let me re-run my calculations and get you the correct beam size immediately" is unacceptable. Even then I do not think I would trust him to re-run. I get the feeling he is practicing out of his depth here.
At this point I would hire an engineer to size the beam, even if it means eating the fee you already paid. And prepare yourself for a bulkhead around that beam, because it is going to be deeper than 9 1/2". The only thing worse than wasting your money on the Arch is wasting your money on the Arch and still having to fix your floor later when it is too bouncy and cracks your gyp finishes to pieces. Get it sized right and move on.
Good luck with the project.
Hi all, sorry to revive this thread but finally got an engineer to size the beam. Based on cost we are going to be using an LVL and a steel beam (or x2 4x6 posts) near the center to support the load. The same beam will be used above in the same position.
I had a question about the steel beam. How do you assure that you get the height of the steel beam lined up exactly perfect? Can you shim above in case the post is not at the correct height?
As far as LVL's, the lenght is 23'-9" so I would assume to just order a 24' LVL and then cut to size correct? Anyone have any other tips or thoughts on things I might have missed?
The sub I use is always perfect, if you find a good steel sub they should tell you how they will achieve it based upon your conditions.
For new posts on new footers my guy makes a rebar cage with double plates connected by allthread. The cage and bottom plate gets embedded in the footer pour, the post is welded to the 2nd (top) plate which has been set just above the footer, and he can raise/lower the post to get the beam dead nuts on the laser at which point he welds everything in place and grouts underneath the plate.
Thanks for sharing that, sounds very similar to installing a lolly column jack.
We are going to be installing this hopefully on our own. Do you have any photos of what this looks like you can share?
Just looking online I did find an adjustable post that is cemented into the floor once leveled.