engineering though it has been a long time and i am not in that field as a career either. I apologize for not being a little more thorough with my description. substrate needs to be properly glued and screwed in these cases, not just nailed down You also need to consider the deflection values for your finished flooring products if its going to be something besides carpet An I beam is unlikely to cost less, at least around here You may need a crane or hydraulic rollers for the I beam though. A crew can probably move LVL's no problem. The installs were compliant but nobody liked them. When LVL's first started getting wide usage here, noticeable bounce was a real issue. Even if it is 'safe' people don't like walking on a floor that they can feel moving. Unfortunately the idiot contractor and architect didn't take life into account. I've been on too many jobs where, yes it works per the load table. With spans that big I would not recommend just looking at load tables and saying 'oh that works per the load table'.
There are however jobs where I leave the Spec work to a Pro. I've dealt with enough jobs, engineers and architects to know what will and what won't work. I've been in the trades my whole life and have no issue designing or spec'ing loads or structural components for 'normal' houses. If you don't have the money, then you probably shouldn't be bigger that monstrosity. Of course if you are building rooms that big you should have sufficient money to hire an SE. So unless you are a licensed SE, hire one. Those rooms are too big for a layman to read books and design it himself. Hopefully this doesn't sound too rude, but if you are building rooms that size you should be hiring a Structural Engineer to do your load calcs. any information on the beam size would be appreciated. The room is 34' x 25'8" and the way it is designed the beam should span the 34'. it seems to me that a single I beam is more cost effective than all this lumber. I have all the formulas for calculating the size of I beam needed but i would like a little reassurance from some other professionals. i have redesigned the lvl support beams as to where it will work but i am increasing the amount of material as to where the cost is getting high. the reason this became an issue is i have another room with a 34' span and a lvl beam will not work because of deflection.
instead of using engineered lumber, would it be more cost effective to use a single I beam for the main beam and the tributary. there is also 3 - 24" lvl's that t into this beam about half way that spans 21.5' also supporting joists. in the icc joist table i used live load 20 psf and dead load 10 psf to calculate joist sizes. i have 4 - 24" lvl's to carry the load over the 29' span. I don't know too many reputable builders who deviate from the approved plans because it opens them up to liabilities.I am designing my house and i have a room that is 29' x 41.5' with 2 different ceiling heights. Ask your builder if he is following the plans or ask to look at the plans to confirm that this was part of the initial design. Many permit offices will require engineering if there are no span tables available for the specific application. If a lumber rafter of similar or less size can work here, then the LVL definitely can as well. Using your numbers, the rafter span you are looking for in the code table 10'-1 11/16" An LVL is manufactured without the natural defects that can be found in lumber, therefore an LVL can deliver better performance than a similar sized piece of lumber.