Home Page link

Floor joist sizing

Building Construction - Building Construction Industry Discussions. 

Page 1 of 3       1 2 3 > last >> Bookmark this page:  YahooMyWeb Yahoo!  Google Google  Windows Live Favorites Windows Live  del.icio.us del.icio.us  digg digg  Add to Netscape Netscape
Subject Author Date
Floor joist sizing Steve Barker LT 10-18-2006
If you were  Registered and logged in, you could reply and use other advanced thread options
Posted by Steve Barker LT on October 18, 2006, 8:36 pm
I'm replacing the lower level floor joists in a 135 yr old farm house.
Basically sitting 6" off the ground on a rock foundation. The current joists
(what's left of them) are rough oak 2x10 on 24" centers. Length = 15.5'.
If I go to 16" centers and support them in the middle, would a 2x8 Douglas
Fir be sufficient, or should I stay with the 2x10? Flooring will be
underlayment then 1x6 pine planking. (similar to original)

THANKS,
--
Steve Barker





Posted by Glenn on October 18, 2006, 9:12 pm
2x8 habitually spans 12 feet so with support in the middle and
with points of inflection out from the center support, you have
only about 5 - 6 foot of span. So, sure.

> I'm replacing the lower level floor joists in a 135 yr
> old farm house. Basically sitting 6" off the ground on a
> rock foundation. The current joists (what's left of them)
> are rough oak 2x10 on 24" centers. Length = 15.5'. If I
> go to 16" centers and support them in the middle, would a
> 2x8 Douglas Fir be sufficient, or should I stay with the
> 2x10? Flooring will be underlayment then 1x6 pine
> planking. (similar to original)
> THANKS,
> --
> Steve Barker


Posted by Steve Barker LT on October 18, 2006, 10:41 pm
thanks for the reply. that's kind of the way I was thinking.

--
Steve Barker


> 2x8 habitually spans 12 feet so with support in the middle and with points
> of inflection out from the center support, you have only about 5 - 6 foot
> of span. So, sure.
>
>> I'm replacing the lower level floor joists in a 135 yr
>> old farm house. Basically sitting 6" off the ground on a
>> rock foundation. The current joists (what's left of them)
>> are rough oak 2x10 on 24" centers. Length = 15.5'. If I
>> go to 16" centers and support them in the middle, would a
>> 2x8 Douglas Fir be sufficient, or should I stay with the
>> 2x10? Flooring will be underlayment then 1x6 pine
>> planking. (similar to original)
>> THANKS,
>> --
>> Steve Barker
>



Posted by dpb on October 19, 2006, 10:06 am
I had posted earlier but stoopid google-groups seems to have failed so
will make the comment again...

I had suggested I'd stick w/ the 2x10 but hadn't noticed the mid-point
additional support so agree with that a 2x8 is sufficient.

What I would add is that at least in a significant part of the country
trying to get a 16-ft 2x8 in Doug Fir would be like buying the
equivalent in FAS hardwood for pricing if could get it at all. For the
purpose, I'd probably just go P-T for the extra protection from
moisture and chewy critters at what would probably be half the cost or
less. (I tried to get some Doug Fir 1x for some restoration work here
to match some existing work and the local 'yard counter flunkies said
"Fur? What's that? -- Oh? Never heard of it." :( )


Steve Barker LT wrote:
> thanks for the reply. that's kind of the way I was thinking.
>
> --
> Steve Barker
>
>
> > 2x8 habitually spans 12 feet so with support in the middle and with points
> > of inflection out from the center support, you have only about 5 - 6 foot
> > of span. So, sure.
> >
> >> I'm replacing the lower level floor joists in a 135 yr
> >> old farm house. Basically sitting 6" off the ground on a
> >> rock foundation. The current joists (what's left of them)
> >> are rough oak 2x10 on 24" centers. Length = 15.5'. If I
> >> go to 16" centers and support them in the middle, would a
> >> 2x8 Douglas Fir be sufficient, or should I stay with the
> >> 2x10? Flooring will be underlayment then 1x6 pine
> >> planking. (similar to original)
> >> THANKS,
> >> --
> >> Steve Barker
> >


Posted by longshot on October 19, 2006, 6:13 am

> 2x8 habitually spans 12 feet so with support in the middle and with points
> of inflection out from the center support, you have only about 5 - 6 foot
> of span. So, sure.
>

2x6 would span the 5'-6" on 16" centers



Page 1 of 3       1 2 3 > last >>
Similar ThreadsPosted
Floor Joist Beam Spans July 8, 2006, 1:36 pm
Help in sizing TJI for an attic please... January 7, 2008, 11:11 am
Sizing of Towel Radiator October 3, 2006, 12:33 pm
Building stud partition onto tile floor with under floor heating July 12, 2006, 2:54 pm
Learn how floor tile patterns affect the look of your new floor. October 11, 2007, 3:39 pm
Location of Rim Joist March 30, 2007, 4:57 pm
joist question September 27, 2007, 9:47 pm
Joist selection February 15, 2008, 7:33 pm
Connecting a 2x8 joist to 2x4's January 7, 2008, 1:13 pm
joist crack repair question November 2, 2007, 9:30 pm

Contact Us | Privacy Policy

XML SitemapXML Sitemap