Bonus room framing

[Budman]

Hi all,

I've got a bonus room built above a garage (in the rafter space). There is an LVL beam running across the garage ceiling with 2x10 joists lapped over it. However, under the kneewall in the bonus room, there are short joists (about 2 feet long) running parallel to the beam which tie into the rafters. What are these short joists called - lookout joists?

Also, there are short 2x4s at a 45 degree angle from floor joists to rafters - this is inside the knee wall on about every third or so joist (somewhat random). Are these called struts? The rafter span is only about 9-10' SPF 2x8s on 16c - can I remove these struts to gain storage in the knee wall area?

Thanks, Budman

[Goedjn]

Your description doesn't seem to make any sense. Is this a hip roof, or by "parallel to the beam" do you mean merely "horizontal", or does this beam go crosswise from the ridgepole?

Af you have to ask, then the anwers is no.

4' bays should be enough storage anyway,

[Budman]

Gable ends, beam is perpendicular to the ridge. The floor joists are perpendicular to the beam up to a couple of feet from the exterior walls. Then, there are short joists (parallel with the rafters) which sit on the top plate.

I guess I was thinking about this because of Rico's comment about not transferring rafter load to the floor joists (which is happening with the struts).

Budman

[Goedjn]

Yeah, but the knee-wall is already doing that anyway. Which, come to think of it, means that I don't know what the diagonals are doing anyway. Are these pre-built trusses around your bonus-room, or was it all built on site? Do you have any place you could stick a sketch?

[tbasc]

Sounds like O.P. is describing a "room in attic" truss. If that's so, he may be in trouble. TB

[Budman]

Stick built on site, no trusses (2x10 floor joists, 2x8 rafters). The "lookouts" span 2 feet from a doubled joist parallel to the exterior wall top plate.

I guess the concern with these lookouts is that with this setup, there is not much to resist the rafters from pushing out on the exterior walls. It is relying on a toe-nailed connection between these short lookout joists (parallel to rafters) and the doubled joists (perpendicular to rafters).

[Dennis]

They are called braces. They are connected to a continuous purlin which is connected to the rafters. Braces are there to reduce the span of the rafters. It would be unwise to remove them, the rafter may sag in the center if you do so.

[Budman]

Hi Dennis,

I think you are right in that they are called braces (they are about

1.5 feet long). However, they are not connected to a purlin - they are nailed to the sides of the rafters and joists.

The rafter span is only about 12 feet - SPF 2x8s, 16"c, 12/12 slope will span over 15 feet here in the South. Why can't I remove the braces?

[Goedjn]

Because you don't what they're doing, and you don't want to find out by having whatever it is start moving, and because removing them doesn't buy you anything useful. What are you trying to store that you can't store with them in place?