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General => General Forum => Topic started by: 2zwudz on November 21, 2007, 07:21:51 PM

Title: Balloon frame or platform frame???
Post by: 2zwudz on November 21, 2007, 07:21:51 PM
  I am going to build a 20x28 cabin with 12' walls and a loft.  I am wanting to know what type of framing style you guys perfer when framing a loft. There will be a 3' knee board in the loft.  Do you perfer platform framing or ballon framing?
Thanks Mark
Title: Re: Balloon frame or platform frame???
Post by: desdawg on November 21, 2007, 09:19:05 PM
If you are following the slope of the roof balloon framing. If it is a flat topped wall I would rather frame it and stand it up. I am not sure what a 3' kneeboard is?
Title: Re: Balloon frame or platform frame???
Post by: 2zwudz on November 21, 2007, 10:33:15 PM
  I am probably not calling it the correct name but what I am referring to (kneeboard) is the 3' vertical wall in the loft that the roof trusses sit on.
Mark
Title: Re: Balloon frame or platform frame???
Post by: John Raabe on November 21, 2007, 11:44:00 PM
A short wall that comes up about knee height is often called a kneewall.

If your loft will cover most of the main floor area - thus a second floor will a lower side wall, AND the roof structure is supported by trusses or rafters bearing on a centerline beam, then there will be little outward thrust on the short wall and you can safely platform frame the 2nd floor. This is generally easier to do than balloon framing.

Balloon framing has the advantage of no hinge joints in the wall so it can better resist snow and wind loads wanting to push the walls in and out.
Title: Re: Balloon frame or platform frame???
Post by: littledog on November 22, 2007, 10:58:56 AM
I am not a professional builder or anything but since I have been working on our house my opinion is that if you are not doing two full stories then balloon framing is the simpler way to go.  You can frame the walls for both floors in one go and then Frame the floor into the walls.  It just seems so efficient to me.  I am sure if you were putting in a full second story, then platform framing would be better.  I am building a 22X32 with a 6' kneewall and we are balloon framing.  Big 16' walls with the floor ledgered in with 8' walls on the first floor.  The concept just seems so staightforward to me.  Anyway, good luck.
Title: Re: Balloon frame or platform frame???
Post by: glenn kangiser on November 22, 2007, 11:14:07 AM
Good point, littledog.  That is the way I saw it about 20 years ago when I did a 2 story weekend addition to the other house. c*

One thing that I learned when I first read about balloon framing years ago is that expansion and contraction is much more even than with platform framing.

Wood changes size much more,  seasonally, across the grain than it does lengthwise.  Not likely it will affect much but it could give you a variation in spacing on something such as clapboard siding.
Title: Re: Balloon frame or platform frame???
Post by: tc-vt on November 23, 2007, 10:40:38 PM
The other major difference to remember is fire blocking, which has to be added to the balloon framed house.  It may not save the house, but may give the extra amount of time needed to save lives.

Tom