Form and function, my dear marson, form and function.
While the OP may not be building the taj mahal, it does sound like he
is building a room within a living space - note the mention of a
sleeping area for guests. Therefore he might want the room to look
nice, both inside and out. OSB might not fit the bill here from a
"form" perspective, but yes, it would be "functional".
You mentioned 2x6's for the roof and that might be fine for this
application, although the OP did not mention his requirements other
than "it needs to support some load." Without knowing what his storage
needs are (or the size of his guests) I wasn't going to suggest a joist
size. That's up to him to determine based on his requirements. Perhaps
he does indeed have an anvil collection that he needs to store - or
some pretty beefy guests.
As for the extension of the corner posts up the existing joists -
again, if this going to be inside a living area and needs to look nice,
the corner posts would provide both form and function. A secure railing
would not only be functional from a safety perspective, but would look
nice (read: form).
Marson Wrote:
jeez, that sounds like a lot of engineering for a little box. i'd get
some wood 2x4's, maybe some 2x6's for the "roof", some 1/2" osb for the
walls and roof, and you should be good to go. youre not building the
taj mahal. siesmic loads? give me a break. what are you afraid
of--that little box falling on you? i'd think it'd be safer if the
building started collapsing to be in a little shelter. you could screw
it to the floor with some 3" deck screws. for light storage it'd be
fine. (don't be storing your anvil collection up there.)
DerbyDad03 wrote:
There may be a number of code/safety issues to consider here.
If you live in an earthquake prone area, I'd be a little nervous about
a freestanding room, especially one that is going to be top-heavy due
to storage and/or guests.
The top is going to have to meet requirements for a "regular" floor,
since it will have to support the dead load of the storage as well as
the live load of 1 or 2 people climbing into bed. So you are going to
need joists, a subfloor and possibly a finish floor. Go to
http://www.awc.org/calculators/span/...rcalcstyle.asp to
determine the joist size based on what you are planning to put on top
of the cube.
By the way, even if the top of the cube is the full 8 x 8, that's
pretty cramped for sleeping area. A single bed is going to take up over
a third of that space, which I guess is OK in an emergency.
I'm also a little confused by 2 seemingly contradicting lines in your
post.
First you say: My...concern is not attaching the room to the existing
structure.
Then you ask: what is the best way to bolt it to the floor?
So, let's assume it is going to be attached, at least at the floor.
Let's also assume you don't want your guests rolling out of bed and
falling to the floor - which means a railing of some type. Consider
extending the corner posts up to the existing ceiling and attaching
them to the joists of the existing structure. This will give you both a
firm attachment to the existing structure and a firm place to attach
your railings to. Seeing that the cube is going to be top heavy, you
are going to want to have some means to prevent racking. Attaching the
cube to the existing ceiling will prevent that. If not, you might want
to consider bracing on the side walls.
While I've never used metal studs, I do know that they do not have any
real strength until the drywall is attached. I can't imagine how they
could be used as the top plate to support the joists you are going to
need to build the floor on top of the cube.
Finally, If you are planning to brace the side walls, you'll need to
use plywood because I wouldn't rely on drywall to provide enough
bracing strength for a top heavy cube.
Check out these pictures to see the effect of wind on a freestanding
structure that wasn't braced properly.
http://www.unified-eng.com/ch/bracing.html I know you won't be dealing
with wind, but I can imagine that an uneven load on the top of a free
standing cube might eventually have the same effect.
jeez, that sounds like a lot of engineering for a little box. i'd get
some wood 2x4's, maybe some 2x6's for the "roof", some 1/2" osb for the
walls and roof, and you should be good to go. youre not building the
taj mahal. siesmic loads? give me a break. what are you afraid
of--that little box falling on you? i'd think it'd be safer if the
building started collapsing to be in a little shelter. you could screw
it to the floor with some 3" deck screws. for light storage it'd be
fine. (don't be storing your anvil collection up there.)