Opinion on installing larger sliding door

[MarkV]

....or the header is supporting the beam which is supporting the floor joists which are supporting a second story wall which is supporting ?

Davitk I understand what you are saying, not enough information to tell. It sounds to me from what Rich is saying that the beams do not sit on the header and extend through to another exterior wall. If that is the case then I suspect that the other exterior wall could be the load bearing wall if the beams are strucural. It would be unusual for a header on a bearing wall to be built out of 2x6's in my area the way Rich's is.

MarkV

 

[Superduper]

.... Should I drill a pilot in the sheathing?

No, not necessary. Chances are, the sheathing is only 3/8" or 7/16" plywood or OSB. Screws go through it very easily and readily. Only start a hole through the stucco. The code requires that the fastener not be countersunk as it will reduce the holding capacity so DON'T drive the screw too deep. The pilot hole in the stucco should be large enough diameter to accommodate the entire screw head. Otherwise, the screw will crush (or worse) act as a wedge and split/crack the stucco. Making the hole large enough will ensure that there is no stress on the stucco. For best appearance, patch using stucco mix or cement based mix. Caulking or other latex based patches, in my experience, are not as attractive and hard to finish.

 

[mjncad]

Do it right, do it safe and replace the header.

 

[Superduper]

RichT, It looks like 2 plys of 1-3/4" x 7-1/4" LVL lumber laminated/bolted together should give you a dimensional value of 3-1/2" x 7-1/4". If you have 1 inch available above the current 2x6 header, this should give you about 6.5" of space for new header. Measure carefully how much "actual" space you need for your new door because the most doors require some shimming above anyhow and I have seen some installations require more than an inch of shimming. The 7-1/4" size LVL beam looks to be pretty close to what you need. Seeing that the dual LVL beam appear to be suitable to replace triple 2x12's, I think you'll be fine in this regards. Trimming the LVL beam down to 7", 6.75" or even 6.5" should still be stronger than 2x10 or 2x12's but this is just a guess as nobody has a chart for trimming of engineered beams.

For me, I believe I'll be comfortable with using dual 7-1/4" LVL's to replace the current header.

http://www.americandreamconsulting.com/downloader.asp?chartid=1

 

[RichT]

Thx again to all for your help. I've added some pix to (hopefully) better describe the structure. The ceiling beams do not extend beyond the sliding door alcove wall and, I believe, are mostly decorative, supporting the wood ceiling panels. I've identified a common reference point (electrical ref) in the closeup and attic shots. From the attic shot, the 2x4 through which the electrical goes appears to rest on the end of the ceiling beams & cripples, but does not appear (to me) to be a significant load bearing structure. The beams appear to be nailed to the header cripples and rest on the header via wood "inserts" as seen in the expanded closeup.

I believe most of the load bearing is accomplished by a 2x12 which forms the "hangover" of the alcove area. Hope this makes sense.

There is precisely 6.5" between the existing door and ceiling beams, so to SuperD, I would likely have to rip the LVL pieces you describe.

 

[Superduper]

Much better pictures this time, RichT. From what I can see, and please correct me if I'm wrong:

In attic pictures, the alcove gable wall rests on top of a 4x12 beam. There are 2x4's spanning the inside wall and alcove ceiling support beam. The mesh between the 2x4's is probably the backing for the alcove ceiling stucco, right? There appears to be a brace sitting on top of the inside wall top-plate that probably provides additional support for the roof, right?

I cannot see which way the ceiling joists run but if my eyes can be trusted, then the insulation seems to be running parallel with the interior wall where slider is going to be installed, right?

On the inside, the decorative wood beams are quite substantial, if they are solid lumber. Clearly, the fact that they don't protrude past the exterior wall and supported from outside members means that they are being supported by the inside wall where your slider is. Without looking under the insulation in the attic, I cannot tell if the ceiling joists are being supported by those "decorative" beams or if they are supported at the ends. I can see in the interior pictures that those dark colored beams are resting on a shim above the header and are nailed through the cripple studs. Clearly, the weight of those beams are resting on the header.

Ok, presuming that all that is correct. We know that this wall is supporting at least 1/2 the weight of the stucco ceiling in the alcove. We know that the wall supports at least the free weight of the dark colored ceiling beams. We do not know if it supports any of the weight of the ceiling members. We do know that there is some transfer of weight from roof to that wall by means of a 2x brace. While it is not supporting all of the roofs weight, it is probably keeping the roof from sagging by means of shortening the span.

From the pictures, my opinion is: I think that there is no way that you "extend" the header, it will need to be replaced. The wall is clearly supporting some weight but the good news is that it's not as much as there could be. Temporary supports: The two dark colored interior beams are clearly resting on the header and the cripple studs. The alcove ceiling is probably going to be OK without but I'd rather err on the side of caution and toss up a 2x6 supported at the ends and shimmed up tight. Before removing the header, I personally would want to spread the weight of the roof brace across the top plate. The top plate is probably just a couple of 2x4's stacked flat wise. If you've ever walked across a couple of 2x4s stacked flat wise with a 6' or 8' span, you'll know that it will bend readily without much weight. The dual LVL beams should work nicely in this application. Personally, if I know that those decorative wood beams are exactly that: "decorative," I would notch those at the ends rather than rip the LVL but that is just me.

 

[davitk]

I'm going to take a wild guess here, Rich, and I don't think you have any ceiling joists, just beams supporting T & G boards (probably 2" thick). Just be sure to build a temp wall, as Super advises, both inside and outside before you pull that header. Oh, and wear a hard hat

 

[GordonR]

RichT

A solution no one has mentioned yet is to
Make up a flitch beam of the same thickness as the existing header.
You can counter sink the bolt heads to have a smooth surface to finish to.
punch flitch beam into your browser and you will have all the info you will need
just an idea I've used in the past

Don

 

[RichT]

In attic pictures, the alcove gable wall rests on top of a 4x12 beam. There are 2x4's spanning the inside wall and alcove ceiling support beam. The mesh between the 2x4's is probably the backing for the alcove ceiling stucco, right?

Yes, I believe the alcove gable wall is supported by the 4x12. Yes, the mesh is the backing for the alcove ceiling stucco.

There appears to be a brace sitting on top of the inside wall top-plate that probably provides additional support for the roof, right?

yes, there may be another brace from the inside wall top plate outside the camera shot - I'll have to check again

I cannot see which way the ceiling joists run but if my eyes can be trusted, then the insulation seems to be running parallel with the interior wall where slider is going to be installed, right?

yes

On the inside, the decorative wood beams are quite substantial, if they are solid lumber. Clearly, the fact that they don't protrude past the exterior wall and supported from outside members means that they are being supported by the inside wall where your slider is. Without looking under the insulation in the attic, I cannot tell if the ceiling joists are being supported by those "decorative" beams or if they are supported at the ends. I can see in the interior pictures that those dark colored beams are resting on a shim above the header and are nailed through the cripple studs. Clearly, the weight of those beams are resting on the header.

The wood beams are solid 4x6, probably doug fir (?). They don't protrude past the slider wall. Best as I can tell the beams support the inside top wall plate but not the ceiling joists. Yes, the weight of at least 2 of the beams are resting on the header. The beam at the left of the slider may or may not be resting on the header. WOn't know for sure until I remove the wallboard.

Ok, presuming that all that is correct. We know that this wall is supporting at least 1/2 the weight of the stucco ceiling in the alcove. We know that the wall supports at least the free weight of the dark colored ceiling beams. We do not know if it supports any of the weight of the ceiling members. We do know that there is some transfer of weight from roof to that wall by means of a 2x brace. While it is not supporting all of the roofs weight, it is probably keeping the roof from sagging by means of shortening the span.

this would seem to be a pretty good assessment

From the pictures, my opinion is: I think that there is no way that you "extend" the header, it will need to be replaced. The wall is clearly supporting some weight but the good news is that it's not as much as there could be. Temporary supports: The two dark colored interior beams are clearly resting on the header and the cripple studs. The alcove ceiling is probably going to be OK without but I'd rather err on the side of caution and toss up a 2x6 supported at the ends and shimmed up tight. Before removing the header, I personally would want to spread the weight of the roof brace across the top plate. The top plate is probably just a couple of 2x4's stacked flat wise. If you've ever walked across a couple of 2x4s stacked flat wise with a 6' or 8' span, you'll know that it will bend readily without much weight. The dual LVL beams should work nicely in this application. Personally, if I know that those decorative wood beams are exactly that: "decorative," I would notch those at the ends rather than rip the LVL but that is just me.

I'm DEFINITELY replacing the header.

Temp supports: planning to brace the inside beams with a horizontal 4x6 supported by two vertical 4x4s. For the alcove ceiling support would you place the 2x6 at the center of the ceiling span vertically braced at the alcove walls?

Regarding the LVL, rather than notch those beams perhaps I could build a flitch beam per Gordon's suggestion with 1/4 plate (which I have in plentiful supply) sandwiched by two 2x6 LVL pieces. Would this be a sufficient header?

I'm going to take a wild guess here, Rich, and I don't think you have any ceiling joists, just beams supporting T & G boards (probably 2" thick). Just be sure to build a temp wall, as Super advises, both inside and outside before you pull that header. Oh, and wear a hard hat

I believe thats a good guess, the beams support the T&G ceiling boards. Hard hat aye!

 

[Superduper]

..........For the alcove ceiling support would you place the 2x6 at the center of the ceiling span vertically braced at the alcove walls?

Regarding the LVL, rather than notch those beams perhaps I could build a flitch beam per Gordon's suggestion with 1/4 plate (which I have in plentiful supply) sandwiched by two 2x6 LVL pieces. Would this be a sufficient header?

I believe thats a good guess, the beams support the T&G ceiling boards. Hard hat aye!

Yes, the temp support for the alcove ceiling, if using 2x6, should definitely be vertical. a 4x6, would probably be easier to keep upright than a 2x stood upright. I would place it as close to the slider wall as possible rather than at the center.

Regarding converting dual lvls to a flitch beam by adding 1/4 steel plate, that is an interesting suggestion and definitely would add to the strength. The problem you may find is that unlike 2x lumber which has a nominal size of 1.5" thick, the LVL (laminated veneer lumber) typically has a nominal size of 1.75" which doubles up to 3.5", the same nominal size as a 4x lumber. Adding a 1/4" steel plate in between will make the beam wider than the current wall framing which adds a new issue. I believe you can actual get LVL in 3.5" thick as well (I have a chunk in my driveway). I'm not 100% convinced that a flitch beam constructed with 2x materials is any stronger than a 3.5" thick LVL beam. If you've ever seen or worked with them, you'll know what I'm talking about: they are extremely rigid with hardly any deflection. In any event, the strength of lvl lumber is widely published while flitch beams have so many variables that you may need software to calculate the structural load capacities. Notching the ends of the 4x6 beams to sit on top of a full dimensional lvl beam is still the best option, I think. You only need to notch the two and if you feel uncomfortable with this for structural reasons, you can eliminate any loss of sleep by integrating joist hangers onto the ends -- problem solved.

Finally, if the 4x6 beams does in fact support the weight of (2x tongue and groove ceiling planks), that can amount of a substantial amount of weight. Just think about how heavy the cumulative weight would be of all the 2x's and 4x6's and stucco ceiling, and transfer of roof weight.....

In any event, I would think that the final installation, if done using a dual lvl flitch beam, or better yet, a triple lvl beam would be stronger than the original 4x6 header. If the home was built today, I doubt that the 4x6 header used would be permitted.