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.

 

[MarkV]

Rich thanks for the photos, they made things much clearer. Nice house by the way.

I’d agree with what the others have said about what needs to be done to replace the header. You will for sure want to build some temporary support to carry the load before removing the header. It still surprises me the original builder used 2x6 for that header.

Just to bounce another idea around. Have you considered French doors that are designed to open outwards? It would give you the wider pass through and could be put in the original opening.

Hope you will document the process and let us know how it goes.

MarkV

 

[ray66v]

I think I'd loose the decorative beams and blow the interior wall out to meet or nearly meet the outside wall. The outside wall is already headered, (you could have 2 big sliding doors), and you pick up looks like 50-60 sq. ft. of interior space.

 

[RichT]

Superd, I think the final decision on the LVL configuration/notching will be driven by whats available from local lumber yard. Is it OK to drill holes in LVL to bolt together multiple boards? One article I read on LVL said doing that might compromise the strength of the lumber.

Mark, yes we did consider the french doors, but the slider is the preferred arrangement, a bigger one

Ray, wow, thats a little beyond my meager construction skills, but interesting idea.

Thx again all.

 

[hitekcountry]

Another thought, run a 4x12 in the attic area as a strong back and hang- strap the existing header to that. No need to remove the old header.

 

[davitk]

Rich, drilling and bolting a multi ply LVL will actually increase its strength vs. nailing or screwing.

 

[Superduper]

......Is it OK to drill holes in LVL to bolt together multiple boards? One article I read on LVL said doing that might compromise the strength of the lumber.

Obviously, any hole drilled in an engineered peice of lumber is going to have some, if small effect. Generally speaking, the warning on drilling holes refer to larger diameter holes intended to accommodate wiring, plumbing, and other installation needs. I certainly don't recommend drilling any hole larger than absolutely needed to accomplish the bolting together of the beams. A high quality adhesive between the laminations will help keep the assembled beam slightly more rigid, especially since steel-wood has less frictional qualities than wood-wood. Dimpling the steel plate surface with a lot of center punch marks could be of value in increasing the clamped frictional action between the surfaces. But in all fairness, if these minor steps were needed to effect a make-it-or-break-it difference, then the beam would have been woefully inadequate to begin with.

One thing to absolutely avoid, however, is notching of the beam, especially on the tension side. That could have a terrible effect. Think of a plastic bag, very strong, but nick or compromise the bag and it becomes a house of cards.

 

[RichT]

One thing to absolutely avoid, however, is notching of the beam, especially on the tension side.

To avoid me misintrepreting this warning - you're talking about the LVL header? Would grade 5, say 3/8", bolts be OK for joining the LVL planks? Spacing?

 

[Superduper]

Yes, the lvl beam. The 4x6 beam should be ok to notch at the end and installing standard hangers should eliminate any tendency to crack at the notch. If the notch was also cut with a small radius at the corner, this will also reduce tendency to crack. The simplest way to add the radius is to drill a hole at the corner and then make the cuts to the drilled hole. For clarification purposes, notches sometimes could result in a tendency for the beam to crack/split at the corner of the notch and run from the corner of the notch length wise. There are a few methods that are prescribed to reduce or prevent this tendency which are to add brackets, add a lag bolt at the bottom to "pull" or "hang" the non-hung portion from. But again, the simplest is to install a standard framing hanger which allows the beam to be supported at the very bottom as opposed to being hung only from the cut corner. After the sheetrock is installed, what left of the hanger that is exposed can be painted dark brown and will probably be hardly noticeable.

With respects to the bolts used, I am not an engineer but personally, I would not hesitate to use grade 5 bolts. I am presuming that you are going to use many of them? The science of building flitch beams need to be computed all the way down to how many bolts used and their shear strength. You can buy a computer program to do this. Personally, since it does not sound like you are doing this with a permit anyhow, is to use a lot of bolts and be done with it. If you are building a flitch beam with the LVLs, you know that you are going to have bolts protruding on the interior side, right? If you use carriage bolts on the side facing the sheathing, there should be minimal intrusion and the bolts can probably be tightened enough to sink the heads sufficiently. On the other side, however, since the beam is only 1-3/4" to begin with, I don't know if having a couple dozen countersunk holes 1/2" or 3/4" deep is going to affect the structual integrity of the beam.

I would consider "framing" or "trimming" the new slider with huge dark colored lumber which will (1) hide the new extra thick header and (2) match the theme of the roof beams.

 

[davitk]

I am assuming it has been established that those beams are indeed structural, and there are no additional joists. That would mean your header is holding only the weight of the ceiling, which is minimal. The brace you see in the attic would likely be just that, a brace running from the ridge board diagonally to the top plate, and really is transferring little or no load to that wall. That said, a 4x6 LVL header would likely be more than adequate, especially with the addition of exterior structural sheathing; just screw the two halves together. DO NOT notch those beams, you are opening a can of worms that does not need to be opened. And be sure to add that second jack stud to both sides of the new opening. Have fun!

 

[RichT]

And be sure to add that second jack stud to both sides of the new opening. Have fun!

I think I missed your first mention of dual jack studs on each side. Why do you feel this is necessary?