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Andrew:
There are two things that you probably need to re-consider from your original post.
1) There is already a window at that location, but you wish to remove wall below and above the existing.
2) You are on some sort of a hillside. This means there could be some lateral forces from that pushing on the wall; the front wall w/ the hill and the two walls perpendicular to it may be acting in unison to resist that.
The proximity of your opening to the uppermost hillside grade is important. If the planned opening is within about the first 12′ of that hill & corner being resisted, then this being an older home, that rake side wall could be buttressing that front wall at the corner.
If this is the case and you are near the corner you probably want to keep masonry (the 4 ft.) of which you speak, or else, you need to reinforce w/ something.
If you are farther away from the corner than half, or you can determine someother way that the wall is not resisting any lateral load, then you should be able to go up to the bottom of the sill provided there is no vertical loading. Subsequent messages said that your joists ran parallel (no floor loading), and you did say this was the rake side (doubt any roof loading).
Ok, well, I gave the worst-case-scenario; hope this helps.
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Client has a house on a hillside; entire "first story" (below grade) is concrete block built up from foundation, 1 1/2 story wood frame above that. She'd like a sliding patio door (which she calls a "french door"?) through the middle of the ~25' rake end (no load-bearing). There is already a window in this location.
I'm wondering -- the sill plate is only about 4 feet above the top of the proposed door -- wood (oops, would) it be practical to cut all the way from the sill plate to the bottom with a masonry saw and then frame wood within that (i.e., no lintel). Would the split masonry wall be stable? Problems, perils, flames?
*AndrewI've done the following on non-load bearing walls of industrial buildings. I have no idea if it is legal/acceptable/desirable for residential construction (diclaimer, disclaimer, disclaimer :) ). I would leave the approx. 4 ft of block above the opening to tie the walls together. I would place a piece of steel channel at the top of the opening to act as a lintel, with two vertical "trimmers" of steel channel welded to the horizontal piece to support it. This works well for putting a louver in the back wall of a factory. I have no idea how you would trim it. Possibly you could TEKS screw some 2 X stock to the inside faces of the steel to give a surface for the "sliding french door" :) to be fastened to and an edge to help support some wide casing. At least with a slider you won't have to drill and tap for hinge screws. This probably won't work for what you're doing and requires welding and steel that ends up being expensive when bought in small quantities. Just a thought to get the creative thoughts flowing so to speak. Scott
*Thank you, and your answer addresses my fundamental Q, can the wall be separated? Dang, it would have been so easy... As for metal, I'm pretty sure i noticed a source around here for preformed mental (uh, metal) and concrete lintels of various sizes. Anyone else?
*AndrewHopefully you'll get more advice than just mine. I have always worked in a narrow spectrum of construction and it has never been residential. I don't know if you can't remove the block, I just never have, because it didn't make sense for us. Louvers get expensive over 8' tall and wood framing wouldn't be allowed and I don't do stucco (though I would like to learn) Typically a lot of pipe for air and water and electrical conduit is mounted up on the walls I deal with. Maybe your wall is stabilized by the mudsill/joists and you could go with a header and cripples up to the floor. Hopefully we'll create some conversation and interest and you'll get some more opinionsScott
*Your right Andrew, the issues are getting too lofty and cerebral. 12" block typically we use 6" angle iron and weld together once in place. We score between the courses deep enough to install the first half. I usually mud up the header before pushing it into place to create positive surface for bearing. The header should bear upon at least 3" of block at either side. Since the first header is already in place you can cut out the rest of the opening and install the other half...Best to weld. Once we finish the opening has to be trimmed up somehow...stucco is good for hiding things like that.Good Luck
*Hi Andrew: Your idea can work just fine. With out looking at the structure I would not say you could or could not in this case. A few thoughts ( no special order ). Is the wood bolted to the masonry as it should be? Which way do the joist run? How is the floor system tied to the masonry wall. (If I understand your post there is a floor in the area of the sill plate) Are there any cross partitions inside that may be used to pick up some of the horz. loading. Another thing to consider is that if you leave the 4' of block above intact it may crack from one of the new corners you make to the sill anyhow. A least check out your options.Ron.
*The distance is likely less than 4' and I did think I might end up cracking it anyway. Joists are parallel to this wall. It is a 100 y.o. structure so I wouldn't bet on bolts. The "band joist" is a 4x4 beam, at least judging from an area I explored elsewhere. I would poke some holes in the stucco to make sure things were where i thought before cutting; generally the surfaces are finished and inspection is limited.Horizontal loading -- now as I pictured it the house is an intact unit resting on the masonry walls, pressing down only. There's no splaying force such as from a roof. Or am I mistaken? Certainly i would prefer to mechanically hold the two pieces of wall together -- and I doubt the mortar joints between the remaining blocks would do much of this anyway.
*Andrew: I live in western Ne and the wind blows quite a bit at times. I was thinking of any kind loading from the side such as wind ect. From you description I would think the down loading is not that great. I should have written better. Ron.
*Andrew:There are two things that you probably need to re-consider from your original post.1) There is already a window at that location, but you wish to remove wall below and above the existing.2) You are on some sort of a hillside. This means there could be some lateral forces from that pushing on the wall; the front wall w/ the hill and the two walls perpendicular to it may be acting in unison to resist that.The proximity of your opening to the uppermost hillside grade is important. If the planned opening is within about the first 12' of that hill & corner being resisted, then this being an older home, that rake side wall could be buttressing that front wall at the corner.If this is the case and you are near the corner you probably want to keep masonry (the 4 ft.) of which you speak, or else, you need to reinforce w/ something.If you are farther away from the corner than half, or you can determine someother way that the wall is not resisting any lateral load, then you should be able to go up to the bottom of the sill provided there is no vertical loading. Subsequent messages said that your joists ran parallel (no floor loading), and you did say this was the rake side (doubt any roof loading).Ok, well, I gave the worst-case-scenario; hope this helps.
*Very good points. Where do you get 12' -- from the wall height?
*No one recommended calling in an experienced block mason. If possible, I would try to locate the original mason. May have some knowledge about how the wall was originally constructed. I don't think much of the sawing idea. You will wind up with ragged joints that will require a lot of creative finish work to dress out properly. I would consider the following. Put up temporary shoring if indicated. Break out the door way to the sill. Rebuild doorway with blocks cut to size. Grout the cells adjacent to the door as they are laid up. Construct a header out of blocks cut to receive rebar. Extend the horizontal rebar over the filled cells. With 4' above the door you have 5 or 6 courses to work with. I would rebar and grout two courses. A lot of work but you will wind up with a good result.
*Steven,
Joseph FuscoView Image
*Well, SOMEONE (me) did mention that this is a 100 y.o. house. If I can call in the original mason I will consider changing my line of work!Steve, I think you are on the right track. By "break out the doorway" I assume you mean remove complete blocks, then rebuild with full and half blocks according to standard masonry techniques.I reexamined the wall yesterday and found the problem is hardly as difficult as my memory had painted it. There are maybe three courses of block over the existing window top and the sill; the grade is also around the upper half of the window. I don't think there will be any serious structural problems, it just comes down to doing a nice masonry job. Because everything is covered by stucco it is a litle hard to figure out what is where.What is the general rule for when to fill the cells with mortar? Is this to increase compressive or shear strength?
*Just a warning, if you do saw through the blocks, be aware of the dust. When I was first starting out I cut a window in a concrete foundation, I sealed everything that I could think of, the dust went through the floor joist space and into the furnace on the other side of the basement. Got the window opening cut and cleaned up. Went upstairs to leave for the day and found a eighth inch of dust throughout the whole house! Cost about $10,000 to clean it all up! Boy were those homeowners mad!
*I don't know about a "general rule" in filling blocks. I like to grout the cells adjacent to doors, windows and other openings that carry a lintel (compression load). This also strenghtens the opening for jam fasteners (Tapcons)and provides resistance to the shock imparted by opening and closing doors. It may be overkill. I also like to rebar and grout walls on 4' centers. This pins the blocks to the footings (shear)and resistance to backfill (tension). To eliminate cracks I also like to grout in a horizontal rebar in the top course (tension). I am not a block mason and when I specify these enhancements the block guys all say it is overkill. I call it cheap insurance.The house in question is 100 years old. I'll bet the concrete block foundation is a more recent upgrade. The original mason may be mudding up blocks in the sky but then again, he may still be on the job down here. I know an 85 year old carpenter who can still show the collage boys a day's work.