Box/Bay window header - DIY Chatroom

**Scuba_Dave** · 08-15-2009, 05:13 PM

Well I'm preparing to redo the last windows in the house
Currently a bay window
This will have (1) window at an angle towards the left (front of house)
Then the "wall" will run straight back to the new garage
There will be 2 windows in the straight part
Curently I have a TW3046-2 mulled set of windows I'm planning on using
They are 75 1/4" wide by approx ~57 high
Header already exists in bay window opening

There will be cantilevered floor joists below as additional support below
So there will be a floor now in front of the windows instead of a shelf
Floor joists will come out about 22" - currently the amount the bay sticks out
2x10 Floor joists will go back in along existing floor joists for ~4'

I need a header over the windows to carry the small roof load only
Usually I just use (2) 2x10's or 2x12's for windows on an interior wall
This is the gable end of the house
I doubt that there is more then 2x4's in there right now
Will 2x4's work.....2x6's?
Not sure how to size this........

The header will span the mulled windows (75") then continue on another 17" & be securely attached (hanger) to the new garage wall
Thanks

NailedIt · 08-15-2009, 08:59 PM

I like to use 2x10 with 2x4 across the bottom. The smallest I ever use are 2x6, even if 2x4 is allowed. I think the bulk of the load is carried by the floor joists followed by what's transferred to the main wall through the rafters/ceiling joists and the through the header/hanger connection. A nicely fastened shearpanel would further strengthen it up transferring more of the weight to the garage wall. My mother-in-law wants me to build one of those onto her house...

GBR in WA · 08-15-2009, 09:06 PM

If you are using hem/fir - f.b.=1150. a 3x4 (2-2x4) will carry 488# over an 8' span. You are carrying 1' house roof + 1' overhang + 1' ceiling joist = 40# per ft. x 8' = 320# 488-320= 168# under the limit of total load. Not taking any snow load into consideration.
Be safe, G

**Scuba_Dave** · 08-15-2009, 09:19 PM

Thanks for the info
I'll go with (2) 2x6's at a min
I had thought of using the hardi-plank cement board under the windows
But I may fancy it up & trim it out & use white stain
Or I may use rounded shingles to match the front peak
Another ask the wife her opinion decision

Trimmed out like panels ?

NailedIt · 08-15-2009, 10:38 PM

Load transfer paths are affected by points of connection.

Nice panels, but those are aluminum or vinyl, eh? I'm looking at some raised panel molded drywall to use indoors. I wonder if there is a similar fiber-cement product available for exterior?

**Scuba_Dave** · 08-15-2009, 10:54 PM

Yeah that looks like alum panels
I was thinking of replicating it in wood
They do have smooth fibre board - not sure on sizes

**Scuba_Dave** · 08-26-2009, 11:18 PM

Well, back to the drawing board sort of
MIL looked at the windows I have & thinks they are too big
I have the same windows in the sunroom...BUT 9' ceiling out there
So the windows are up higher
Showed the wife how low they would be & she agrees

So we are going with 2 venting side windows flanking a picture window
It will match the (3) front windows, fractional grid on picture window
Hmmm...only good pic of front windows is from Halloween