20x30 One-Story in Kentucky

[stoneturtle]

Hi Everyone!  I posted here in 2010 about our retirement plans.  Well, it's time to start building finally.  We have the 20x30 plans, we've got 10 acres on a hillside in KY, and we can't wait till spring so we can travel there and start work!

We are both technical people but neither of us has ever built a house.  I've helped, when I was growing up, but I never did any of the planning.  I am going to be asking a -lot- of questions.  I hope you don't mind.  Some of them will probably be stupid questions!  We want to do as much as we can ourselves.  It's out in the sticks so there won't be inspections, so I'm going to be asking even if I feel foolish asking.   

I'm drawing out the plans step by step in Sketchup so I can simulate the build, rather than experimenting later.  It's a nice way to spend a winter anyway.

First question.  We're considering putting a beam down the middle, even though the plans call only for beams along the sides.  The reason is that we could then use 2x8 floor joists 10' long.  This will be easier for us to handle.  Do we need to put a pier every 6' on that beam?  If not, what would be a reasonable spacing? 

[John Raabe]

You might look at using engineered joists as they will be lighter than solid wood.

But, you can do a centerline beam supported on foundation piers. The load on the beam and the span of the beam between supports will determine the size of the beam.

I'm assuming you will do a truss roof as those loads will go to the outside walls.

[stoneturtle]

Thank you for the quick reply!  Yeah, we'll be using a truss roof.

I studied on I-joists a bit, but I have no experience with them and found myself intimidated.  I took the path of least resistance and went with dimensional lumber.  But I think I'll suck it up and dig into them some more.

I had my second question ready but if we go with I-joists it won't apply... I'll be back   

[John Raabe]

I did a quick calc on a beam with a 6' span and standard 50 lb/sf main floor loading. It looks like a girder of double 2x10's should work.

[stoneturtle]

Thanks!

Like this then?  I made spacers of 3/4"+1/2" plywood on each side to fill up the AC6. 



This is the opposite side of the same pier, showing that the joints in the built up beam are staggered.



(If this is right I intent to keep on with the blocking, I've not overlooked it, just stopped to make sure I had it right.)

Assuming I have that right (there's that assume word again...), here's my next question...

I can't overlap the rim joist, it seems to me.  Is this an appropriate way of dealing with it?

[John Raabe]

One option you might consider is to push up the girder and butt the joists to it. You could use face-nailed hangers or nail a ledger along the bottom of the girder and bear the joists on that.

This would give you easier access to the crawlspace.

[stoneturtle]

Oh... oh that's smart...much less kludgey...