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Re: WOOD: "Economical Spacing of Rafters/Joists"

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Bill
We almost always use 24" spacing up here in a roof.  We
don't get your winds, but we get an awful lot of snow--near
Buffalo.
Gary

On 17 Aug 2004 at 15:42, Bill Polhemus wrote:

> I will probably get around to doing this myself but I thought maybe
> some of you have already been through the exercise and have your own
> opinions.
> 
> 
> 
> As far as roof and ceiling framing is concerned, I tend toward a
> "standard" 24 inch spacing for the rafters and joists, use No. 3 SYP
> is possible and choose depths accordingly. Contrary to what some here
> have opined regarding "wind uplift," when you are doing a home in the
> Houston metro area, a rural location here gives you AT LEAST 110 MPH
> (3-second gust) and Exposure "C", which can really kick the h*ll out
> of a rafter with a long span, so the depth becomes an issue. I tend to
> like 8' nominal myself.
> 
> 
> 
> Anyway, just had an architect send back my plans, with the comment
> that "you've got 24 inch spacing, we always use 16 inch," and "why are
> you using 8 inch deep rafters? 6 inch should always be 'good enough.'"
> That was the essence of his complaints.
> 
> 
> 
> Of course, the latter issue is influenced by the former-he didn't seem
> to have considered that at first, but as we talked he saw what I
> meant. However, to him, 24 inch is just "not done". When I asked for
> his reasoning he said "roof deck spans better," etc. 'Course, if the
> roof deck is selected as per the code, this is a non-issue, but I
> don't like to disappoint a client so I deferred to him on it.
> 
> 
> 
> My point was that I thought a 24 inch spacing is more economical, even
> if you use 8 inch joists as opposed to 6 inch.
> 
> 
> 
> I'd like some input from others here on this question, limited
> initially to the economic comparisons.
> 
> 
> 
> If you want to pontificate further on other issues as to why one
> spacing would be preferred over another, feel free.
> 
> 



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