Page 2 of 2 < 1 2
Topic Options
Rate This Topic
#25126 - 01/11/11 02:34 PM Re: Joist Sizing [Re: TIMBEAL]
Jim Rogers Online   confused

Member

Registered: 03/14/02
Posts: 1661
Loc: Georgetown, MA, USA
Originally Posted By: TIMBEAL
What is the rule for pocket depth?


At the class I took at Heartwood school where they taught us beam sizing and other engineering stuff, they gave us this rule of thumb for floor joist to sill beam situation:



We also learned that you should size the joist first and then size the timbers to hold up the joist next. And work you way down to the foundation, making timbers large enough to hold everything up properly.

If that is the case, then maybe the sills in this extended frame will have to be deeper to be stronger.

As I mentioned just adding a supporting sleeper under the middle may solve the problem without changing a lot of joints and beam sizes.

Like this:



He would just have to make it so his foundation would support the ends and add a pier to the middle.

Jim Rogers
_________________________
Whatever you do, have fun doing it!

Top
#25127 - 01/11/11 02:43 PM Re: Joist Sizing
Paul Freeman Offline


Member

Registered: 02/24/99
Posts: 137
Loc: Lyndeborough, NH
That's perfect! Notice the "scooped" out notch, that's exactly what we do to avoid the whole horizontal shear issue. If you run the calcs for square joist notches there's no way that would work on your longer spans, but the gradual transition works great.

But, if you add the midgirt like you show in teh picture it won't be an issue anyway, unless the floor load was very high because you're bringing in a tractor something.

Nice examples, thanks Jim (and Tim!)
_________________________
www.brookspostandbeam.com

Top
#25132 - 01/12/11 02:02 AM Re: Joist Sizing
Andre L Offline
Member

Registered: 01/08/11
Posts: 3
Loc: Ontario
I like the sleeper idea, I'm gonna run with that one. I won't be bringing in any tractors!

Thanks for all the help!

Top
#25134 - 01/12/11 02:15 AM Re: Joist Sizing
Paul Freeman Offline


Member

Registered: 02/24/99
Posts: 137
Loc: Lyndeborough, NH
Make sure you size it right, a support in the middle would help significantly.
_________________________
www.brookspostandbeam.com

Top
#25135 - 01/12/11 04:32 AM Re: Joist Sizing
Dave Shepard Offline
Member

Registered: 02/19/06
Posts: 718
Loc: Alford, MA
I'll be using two sleepers to support the threshing floor in my current project, as the span is almost 10'. The sleepers in turn will be supported by three Samson beams, as they are about 45' long.
_________________________
Member, Timber Framers Guild

Top
Page 2 of 2 < 1 2

Moderator:  Jim Rogers, mdfinc, Paul Freeman 
Newest Members
Janne_Sweden, Whiskey_I, justified, Frank_S, cwhitepoplar
4929 Registered Users