Dead load for wood framing 1

[MHAGGAG85]

Hi,

I am a structural engineer used to work in Egypt just moved to USA I used to work with concrete so my experience is limited with the wood framing and I am working on a 4 story hotel building with a concrete podium and 3 wood framing stories.

I have a problem with determining the loads especially the dead load, for Live load its according to with ASCE 7.

Now for Dead Load for floor framing for example its the own weight for the floor so if I have a 16" deep floor truss spaced @ 24" OC do I have to figure out that to get the dead load in psf for that floor framing or there are tables for that assembly that could tell me the dead load for that kind of structure also what other types of dead load I have to consider. the common practice we do in Egypt is adding a distribution load on the floor for example, the finishing and partitions walls are there is any tables or rule of thumb for the other dead loads aside of their own weight for the element

 

[jayrod12]

Generally speaking, unless the wood floor has extra Mechanical and Electrical allowances, or concrete toppings, or something abnormally heavy on it, the dead load of a wood framed floor with drywall on the underside is around 15-20 PSF, not including partitions. I usually throw in 10 PSF for partitions personally but everyone deals with partitions slightly differently.

 

[MHAGGAG85]

jayrod12 thanks a lot that's really helpful I am kind of having a hard time already due to units difference from metric to Imperial.

what about the Roof dead load as own weight and do you add any more dead load on it aside of its own weight?
thanks again

 

[jayrod12]

Yes. Depending on the intended usage of the building. For commercial projects there's always some M&E and miscellaneous stuff hung from the ceiling/framing, so I'll throw in an additional 5 or 10 PSF. For a conventional wood framed roof, i.e. shingles/metal roofing on plywood on trusses with ceiling drywall I'm usually using 15psf.

 

[MHAGGAG85]

So its

- wood framed floor w/drywall underside => D.L = 15-20 psf
- partions => D.L = 10 psf and its slightly different
- M&E => D.L = 5-10 psf added for comercial.
- conventional wood framed roof => D.L = 15 psf

I know that this is just common practice and its different from one to another designer but at least this gives me the guide that I am seeking, which I can't get in the office.
thanks

 

[Aesur]

When considering the dead loads, it is best to look at the architects sections and see what exactly the roof or floor consists of. From there you can start summing up loads of each layer. You will need to consider things like MEP (Mechanical, Electrical, Plumbing), Fire Sprinklers, type of flooring, sheathing, structural members, insulation, fixed partitions (non-structural walls), miscellaneous, etc. Keep in mind that if the partition locations are subject to change, they are considered under live loads, see ASCE 7-16, section 4.3.2 and are actual weight but not less than 15 psf. Where partition loading per 4.3.2 is required see 12.7.2 for the application for seismic forces.

Additionally I have attached a weights of materials document that gives some good guidlines for the varying weights of different materials.

 

[MHAGGAG85]

@Aesur thanks for your respond, yes I will do that now I have a better understanding. I also got examples from woodworks.
let me ask you guys a question so as I mentioned, I am working on a 3 story wood frame structure over a podium slab.
located at AE zone 140 mph wind speed first wood framing project for me since we don't use wood framing in Egypt first design experience with kind of wind speed.
first time working with masonry walls which exist in this project on the first floor and has to be designed to resist flood load. don't use it where I came from to basically we use concrete and steel.
in my office, they gave me this project to design and I am taking a long time because I am doing a lot of researchers to figure out all that new stuff for me. now they blaming me taking a long time knowing that I don't get any kind of guides because the PE engineer in the office is always busy so I cant get with him and his experience is more related to civil projects.

I want to know averagely how long should that type of project take? knowing that I am working on this project solo no other designers working with me.
I know my skills and I know that I can get it done but it will take that much time for me to get it done right.

any advice I don't have experience with the office work environment here in the states, appreciate your help.

 

[Aesur]

@MHAGGAG85 can you share a screenshot of what the project looks like, it is difficult to put hours to a project only knowing the basic information you have provided? Project time is based on many factors, including experience, size of project, complexity, client, materials used, location, etc.

I hate hearing that you have been kind of left out on your own to design this project, I see this far too often, and in reality the EOR, presumably the PE you mentioned, should have an active role in the project. The more experienced engineers should make time to provide adequate training, especially to those employees who are actively seeking the knowledge as you appear to be on here, or should stop taking on projects that they are not adequately staffed for. While I don't doubt your ability to finish this project, you should definitely ask for some mentoring from the principal/project manager.

 

[MHAGGAG85]

Here is some pictures, let me know your thoughts

 

[Aesur]

Based on what you shared, accounting for only the project and no other variables (like client, how many times things will move around, learning, etc.), I would estimate around 100 hours for engineering + redlining and another 70 hours for drafting.

 

[jayrod12]

Around here, fees for a project of that size would be around 1% of the construction cost excluding site works. But that includes construction phase services as well.

 

[Aesur]

@jayrod12, I wish we got fees that good here. Ours range from 0.25% to 0.75% depending on project type, but the project above would be around 0.50% here.

 

[jayrod12]

And we generally just break even if we're lucky on that level of fees by the time it's all said and done when comparing against our hourly charge rates.

But that's the going rate in these parts.

 

[MHAGGAG85]

and how much a project like this would coast averagely?

 

[jayrod12]

That varies significantly by region. Rsmeans or hanscomb literature can help you there.