10 dead load

[rakuz66]

I think I understand the concepts of dead loads, but what does  a dead load of 10 mean when it comes to ceiling material??  In other words, is using 5/8 sheetrock on a vaulted ceiling with 1/2 in decking and shingles more than a 10 dead load? 

[Willy]

Dead Load is the wood, roofing material, sheetrock ect. that is part of the accual built load. Now added to that is the designed live load that would be like snow that fell on a roof and added to the load. Live load is also a movable load like people, furniture that is added and moved around later. The 10 lb dead load probley covers standard building materials and roof but may not cover a T&G Deck Wood ceiling or Slate-Tile roof. This load differers from area to area and depends on snow loads, roof materials, high wind areas ect. There will probley be others posting a better discription of this later. Mark

[glenn kangiser]

That would also mean 10 lbs per square foot for the total weight of the building materials in that square foot.

[rakuz66]

Thanks , the reason I ask is that I'm ready to cover up my vaulted ceiling and according to code I'm ok as long as I stay at 10 dead load on the ceiling.  Now, how do I know if I'm over 10??  My thought was to weigh a a 2'x2' piece of sheetrock vs a 2'x2' t&g pine. 

[John_C]

It doesn't need to be that precise.  The 10 psf  is an approximation for normal building materials.  If you aren't doing something unusual, like a barrel tile roof or 2x6 ceiling, you'll be fine.  What's up there now?

[rakuz66]

Nothing John, just insulation between the rafters.  Just curious as to what is considered 10 dead load for ceiling material.  I want to use 6" t&g white pine for my ceiling.  That seems to be just about the same weight as sheetrock, I would think 

[glenn kangiser]

Should be similar and not much of an issue.

[John_C]

If you want to get specific the better carpentry books have the psf weights of most materials.  Also the R values of everything you could use for insulation and the "film" of dead air adjacent to each surface.  I suggest saving it for some night when you have insomnia.

Other than that it won't matter if yours is 8.7  or 11.2 psf.  A structural engineer probably wouldn't bother either.  They would take a conservative estimate of the live load and any small difference in dead load would be irrelevant.