1.5 Story Framing ???'s

[MNJon]

Mainly for John R, but anybody who can answer please feel free! I think I am going to go with the 1.5 20x30 and increase to 24x36. My plan is to make a full size loft, so my main questions are regarding the spans.

I have my own sawmill and a large pile of Red and White pine logs. The problem is I can only cut 14'. I could add to the track, but my current supply of logs maxes out at 14' anyway. So, I would like to take the 1.5 story plan, set on a pier foundation, use balloon framing with 12' 2x6 studs. I would like to support the loft with a ledger all the way around and use a center beam to hang, not set on, my beams. Can I safely expand the plan to 24x36, use three 12' beams supported by a post at each joint to make a full length center beam and hang the floor joist beams off the center beam using heavy steel hangers? What should my spacing be, 2' OC? I will be using 1X rough cut for both decking and finished floor.

I can cut whatever size beams I need, so if possible, what size should I use for both my center beam and floor joist beams?

Then for the roof I was planning on using a ridge board and 2' OC 2x10 rafters. Sufficient?

Thanks in advance.

[John Raabe]

Here's an overview of what I would suggest. Run a beam supported at 12' at the main floor, loft floor and roof ridge. These will carry 1/2 the loads of each floor and the roof. You will have two exposed post to include in your interior design. Now you can have the foundation piers at 6' o/c supporting the sidewall loads. These carry the other 1/2 of the wall and roof loads. Size and brace these piers well. You will want to size the beams locally to wind and snow requirements and determine if your lumber needs to be certified. (Check w/ your jurisdiction).

The 2x12 roof rafters over the loft are not pushing out on the walls, so this allows your wall framing to be standard platform framing and the loft kneewall to be whatever height you want. I use 12" deep rafters for insulation depth. You may not need them that deep for your snow load.

[MNJon]

John- Wow, that is awesome! Thank you. I had hoped I could do it, and that is how I pictured it. I am in MN, so the snow loads are high, but with a good roof pitch and a metal roof I am not too concerned with the snow sitting all winter. There are no codes or inspections I need to comply with, but I want to make sure the house outlasts me!

So if I place posts, let's say 10" peeled logs placed at the 12' marks on both levels (which the main would be above the piers, then the second floor would be on top of that, right).

What dimension do you recommend for the loft floor beam and the ridge beam?

Should I notch the logs so the loft beam and the ridge beam ride inside it and then thru bolt them with carriage bolts? If I do that, then do I can use hangers for the floor joists on the main level?

What dimension does the main floor call for, both stringers and joists?

Thanks again-Jon

[John Raabe]

My sketch would only be a start for more of a work-up locally. I know nothing about log timber connections or log beam sizing, so for those you need to find someone local to help - probably an architect, home designer or engineer who knows log timber construction. Yes, you could use peeled logs like you suggest for the verticals and bring those loads all the way down with solid bearing at each floor to rest on a good sized foundation pad. You need to have a load trace done to accumulate these loads and find out what they are. To carry this weight onto the soil these pads might be something like 24" square and 12" thick with 2 #4 rebar each way. Again, I'm not designing this, only giving you a general idea. If you are doing a pier foundation rather than a crawlspace these pads should be sunk down to frost depth.

A standard 2x10 joist at 24" o/c can span 12' for the floor and loft joists. You can hang these between the beams from joist hangers.