Hi,
May have gotten myself into a bit of a jam here. Started replacing all my aluminum windows to impact resistant vinyl. I had a bay window with a large middle window. Took me a while to get it out without breaking it. The mulls on each side were a 2×2 steel post with furring to make the 45 deg. These had to be removed to install the 45 deg bay mulls supplied by the window manufacturer. The 2×2 steel post did not appear to have any weight and felt loose. I’m hoping these post were only there to support the large middle window and not for load bearing. House is single story block. Appreciate any input.
Mike
Replies
MB
I think I remember mentioning when looking at the window photo, that the roof load was probably being carried by a header in line with the exterior wall. If I'm remembering right, there should be no load out at the bay.............however, what "holds" it up? Cables evidently don't run down from the overhang/rafters. But those steel tube/angle might be bolted top and bottom? This would hold the weight of the windows from above (assuming that's put together properly).
Am I close?
Thanks.
I think the ceiling joist just extend past the wall.
Mike
Was there any evidence that the outter corners of the bay was "hung" from above?
I'll have to take a look at those photo's you posted b/4.
Mike
I couldn't find one showing below the window-Is there a wall below w/foundation along the perimeter of the bay?
thanks.
Yes. The bay has a foundation wall. I'll take a pic and post
Here you go
Now it's coming back...............
Mike,
You removed the tube metal?
Here's a reply to you a while back-note that the tube steel is what I referred to as "something holding up the lintel".
Mike (post #207550, reply #7 of 8)
by
calvin in reply to MBaybut [original] on Tue, 03/05/2013 - 05:11
I can't say as I've seen this set up b/4, but there's some structural corners there buried in the metal. Something is holding up the lintel. You'd have to open up the covering either in or out to find out what. Inside, there's a header spanning the opening-most likely straight across with a bulkhead dropped from above to make the angle (or a flat return) back to the header.
You mentioned earlier in this post about the steel being loose?
If the corner reinforcements in the new windows are not structural, you'll need to make it so.
That they were loose in the old units seems odd.
If the steel tubes were just stuck in there then I doubt they were holding much of anything. However, even if they were the new impact mull bars you're installing will do the same job just as well if not better.
I hope that's the case. The new mulls are pretty beefy.
Mike
What did it look like above when you pulled the old frames?
We first took out the side windows. The large middle window was on a track. We removed the post to facilitate sliding the window out. Pulled the large window out then removed the other post. The post actually seemed to be part of the window frame. I was thinking that because that window was so large (84x80) it had the steel post to stop it from flexing.
Mike
What is the lintel attached to?
the new mulls
You took out the support for everything above the window, including the roof! No carpenter will ever use steel in a corner if it's not needed for structural reasons.
There is no way a replacment bay window will come with a structural corner designed to hold up anything. They are designed to fit in an opening that is already self supporting.
The only reason metal was used originally is to save space and avoid having a wood post. Code would probably require doubled studs at each corner - depends on your snow load, but this is obviously not being inspected.
The main problem I see getting in the way is that your new window was too wide for the original vertical supports, so with that window you're now too wide to get anything under the header that is in the framing above the window. It doesn't do you any good to put some kind of support in there if it's not going to hit the ends of the headers.
There is no way that you can just put this window in and not have the lintle sag and lose bricks along with the roof sagging.
You have some interesting problems to overcome to fix this correctly.
Edit: If there is a header inline with the wall and buried up in the ceiling then you have a few less problems, but I'm guessing that's not the case if you described the ceiling rafters as spaning out into the bay. A header across that area would support the roof load and it looks like there's room in the attic to retrofit one. If you do that then the only thing the lintle has to support is the weight of the bricks above the window and it's then possible to remove the window and fit a new longer lintle (assuming the old lintle was sized to match the steel posts you cut out, which would make it too short now).
You haven't seen an impact window mull bar have you? Also, this is Florida construction so I expect the roof is trusses and the "header" is really little more than filler. We don't have snow loads and the bay probably doesn't extend out far enough to have much dead load.
I spoke to the building materials supplier. He pretty much confirmed what you are saying. The brick fascia is supported by angle iron. The header above the bay now has 3 mulls instead of 2. I split the big middle window into 2. Has I said in the earlier post the steel post did not appear to have weight on it. I could twist it around by hand. It only had 1 screw holding it in.
Thanks
Technically the suport provided by the mulls is not correct and there may or may not be a proper load path. It would be dumb luck if the center mull had a stud directly below it, but there's a good chance it's a double plate under the window which would carry a lot of weight. Like I said, it's technically not correct, but may work.
Having said that, your loads aren't much and what you have in there now may work out just fine in the long term.
I'd imagaine any problems won't crop up for quite some time if ever, but it would be a shame for the lintle to sag and cause problems with the brick. A remodeler stripping your house down to the studs 50 years from now will be the best person to ask. Your windows look great though.
Best of luck.
It doesn't look like there is any kind of header over the window opening other than the part directly above the window so the rafter would be supported by whatever verticles are on the 45 degree corners supporting the header above. That being said, the truss can be resting on an interior wall and it would be stiff enough to not put any weight on the exterior, but that's probably not how it was designed.
Honestly I really like the steel mull bars on impact rated windows, but most are designed for side impact and lack any kind of bearing surface above or below, which is easy to fix with a flat steel plate between the bar and wood framing, but for structural purposes most steel mullions are probably still on the light side. If space is limited, it's easy to retrofit a solid steel bar that would provide more beef in the same space.
I'm so conditioned to think of snow loads that when a house comes up in a place with no snow it throws me for a loop! lol I guess there's not much weight up there.
Nonetheless, I think the problem still exists that the header is too short since the original square steel tubes had to be removed to make room for the new window?
All this is much easier when seen in person. :)
The steel tubes were only removed because they were stopping the large window from sliding out. The new mull are actually wider so the header is long enough. I did decide to slip a plate between the mull and the header. I think I'll be OK. I want to say thanks to everybody for helping out here and brainstorming my problem.
The impact mull bars are 1/4"
The impact mull bars are 1/4" aluminum extrusions and do have quite large plates top and bottom. ssince they have to be screwed to the header and sill. I realize they weren't engineered to hold the roof up but since he could slip the steel tubes out by hand it doesn't sound like they were either.
What you have is not an uncommon problem and it normally requires a little thought to squeeze in enough beef to support what's above the window. Without being there to see how your window is put together it's hard to say exactly what is the best fix, but my guess is that the window muls can be modifed or replaced to support the weight. The negative to this fix is it causes problems if you ever have waranty issues since you're modifying the window.
In one case I had enough room for the equivelent of a 2-1/4" x 4-3/4" odd shaped post on each corner if I threw away everything the factory used to make the corner - not technically enough for normal framing. I was scratch building an oak staircase and ended up making the corner out of a few layers of thick oak glued up with a structural epoxy. In this case it was more wood than the original window had for verticle support so it passed inspection, but it wasn't supporting the roof.
If at all possible putting the 2x2 steel back in place is the least complicated, otherwise we need more information about what's above. If nothing above is usable I've added new headers from the inside that had breaks over the verticle supports and the lintle to support the brick was then hung from the header. One way or another, make no mistake about it, both the brick and roof need to be supported by something.