masonry, how to handle CMU T-intersections

I've laid out the base course of a structure using 8x8x16 CMU (on the PC, not real world). The course includes rooms, hallways, openings for doors, and several T intersections. I have the option of having the intersecting CMU rest against the other wall or to be placed inside it so that it will interlock as courses are added. However either method leaves me needing 8x8x8 CMU to fill the gaps left in every other course around the intersection. Openings for doorways would also require these smaller blocks. I'm a novice at best but this seems like it would be a common problem.
My questions are:
1) Should the intersecting wall interlock with its "host" wall, or be built up beside it and attached to it with other methods?
2) Would the use of 8x8x8 CMU at wall intersections every other course reduce the structural integrity of load-bearing walls? The walls will ultimately be around 36' high.
3) Assuming my questions are founded in perverse misunderstanding and ignorance, what would your run-of-the-mill mason do in this situation?
Thanks in advance.
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I really dont see the need to change how we have refered to BLOCK for the last.....forever but somebody did and it really irratates me.....having said that...

interlock for strength and sheer.

these are called "halves" as in a half of a full block. Since block are modular in measurment and structurally laid at half bond it would be impossiable to build a wall or any sturucture without the use of halves.

snipped-for-privacy@gmail.com wrote:

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block ties and go,go,go I need 650 blocks a day or I'll get your money
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It would be quite unusual to interlace partition walls, I don't know that I have ever seen it. It would be normal to tie the reinforcing of each wall together. This would not do away with the need for 8's, in fact it would probably increase the count. If you were to interlace, it would restrict intersecting walls to modular locations.
36' walls will need pilasters, sheer walls, or some form of stabilization. If the walls are load bearing, these issues become even more important. The walls will need vertical control joints to prevent cracking. Block walls require reinforcing both horizontally and vertically at roughly 4' on center and each side of all openings. How do you intend to handle headers at openings? Do you intend to insulate? Will the block be exposed both faces? What are you designing? Electric and plumbing in the block or surface mounted? Foundation and soil bearing requirements for that tall of walls will be substantial.
______________________________ Keep the whole world singing . . . . DanG (remove the sevens) snipped-for-privacy@7cox.net

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DanG wrote:

I think I'll go with interlacing, as all the walls are snapped to an 8x8" grid and I don't want to have to worry about ties if I don't have to.

The overall structure is 64x64' and square. I misspoke earlier when I said the walls would be 36'. The building will be 24' (two floors) except for the center, which will be 36'. The center is a large room that is 24' high without an intermediate floor. Its walls continue up to 36' to form a smaller third floor.
Three pilasters/buttresses are distributed evenly across each of the four exterior walls, formed by interlocking CMU. I plan on reinforcing them with rebar and filling them with concrete. Are you saying that something like rebar will need to run vertically every 4' and that horizontal reinforcement will need to be between every 6th course (4')?

I plan on having round arches at each door opening and lancet arches for windows. I'll measure and cut these myself from solid concrete blocks, or possibly use natural stone.

All CMU is splitface. Where windows must occur the CMU will be back to back with no space between, which should provide sufficient insulation with water repellant/sealant applied to both sides. The four exterior walls consist of back to back CMU with no space. The interior walls are arranged similarly but with 2' of space between the back sides of the CMU. The 2' of separation provides a continous unfinished "utility corridor" running around all rooms and halls and will house electrical, ventilation, and plumbing for easy access/maintenance.
As far as the walls being load-bearing I'm still not certain. I was thinking about using large timber frame construction for the center room and reinforced concrete columns supporting precast reinforced concrete groin vaults for the rooms. If I can help it I do not want the walls to be load-bearing since it will make things more difficult.
The structure will be built in the suburbs of Atlanta, GA (USA), and will be my primary residence. I do plan on having an architect give unofficial approval of the final design before construction begins, and hiring contract labor when absolutely necessary. I'm a big DIY kinda guy so I'm trying to learn everything I can. You've all been helpful and I thank you.
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snipped-for-privacy@gmail.com wrote:

Oh, well then, if you're getting unofficial approval it should be unofficially okay.
R
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Thanks JerryD(upstateNY) and RicodJour for those highly useful last comments. My original question has been answered, and I was responding to additional questions DanG had raised. Let's try to keep things solution-oriented rather than "you don't know what you're doing and are going to die"-oriented. Jeeze...
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snipped-for-privacy@gmail.com wrote:

You wrote this: "3) Assuming my questions are founded in perverse misunderstanding and ignorance, what would your run-of-the-mill mason do in this situation? "
I did not realize you were being factual in asking us to make that assumption.
You asked some questions about a project that I wouldn't hand to a "run of the mill" mason. You asked questions that made it obvious that you are playing with some computer software to design your dream house and that you have no clue about construction.
Your comment about asking an architect for an "unofficial approval" is inane. If you're playing at being a big boy and taking risks, well, hell, just do it. What's the worst that could happen? If you're done playing at being a big boy and want to actually do what the big boys do, then get professional help when you need it (now). The few bucks spent will keep you from spinning your wheels and wasting your time.
BTW, DIY does not mean reinventing the wheel. There's no shame in learning from a professional, even if you have to pay them.
R
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Kevin, I read your description of the project details and minus the negative comments Im sorry but I have to agree with JerryD. I appreciate your DIY attitude because I myself very rarely hire out stuf I have to do at home. But part of being strong is realizing our weaknesses and when it is smart to let others take over+++++++this is not a homeowner project++++++ the general design and orintation you could do but even this may/probably will be changed drasticly from your vision because of eng. and building code issuses. This is just one of the issues, you will need several people to be able to lay the block even at the ground level and more once you get onto the scaffold----32' high is 6-7 frames high of scaffold (one frame every 7 feet x 6 or 7 high) ....scaffold that must be the length of the wall which will be working on and will include planks, mud boards, mud stands, a pulley or lift to get the block and mud up you will need some one on the ground at all times to mix and chase materials you will need to get the rebar up there you will need somebody cleanning the joints and more than likely the block since you have not laid block before++PLEASE NOTE++ split face is THE HARDEST TO KEEP CLEAN once you get mud on the face its very hard if not impossiable to get IT off. You are going to need even more scaffold for the floor area because unless you do each wall individually you will still need to build leads around the corners ready for the next wall. you will need a comercial mixer, a rebar bender and cutter, a mud box, a gas cut off saw a forklift to move the pallets and pallets of block and cement around you will need a couple of wheelburrros, lots of string line, chicken leggs........shall I go on? Not to mention the fact that not knowing how to lay block....even if you did know how and were an accomplished mason you can really only lay (trying to do all this yourself) a few hundred block a day if that. The average apprentice union mason is expexted to lay about 3-400 block a day and thats with a support team..you will have to have all open end block to get over the rebar which are much more exspensive than standard splits if this partition wall is going to be exsposed inside you will need dbl.splits which are again more than reg and even open ends. Not to mention the sheer pain in your back, legs, and arms from lifting the blocks even if your 25 years old. Again I don t want to smash your dreams but this is not for you. Think of it this way even if you were to do everything with help from friends the amount you would spend in equipment rental or purchase would pay for the project to be done by someone else. and if this is a house you are going to need the energy to deal with the countless hours of other crap that is going to come up and believe me it will.....
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Let's try to keep things solution-oriented rather than "you don't know what you're doing and are going to die"-oriented. Jeeze...
The solution oriented answer is for you to get an engineer to draw up what you want and the get a mason contractor to erect it. I didn't say anything to be funny. You have no idea what you are getting yourself into. I have seen block walls blow down on construction jobs where everyone knew what they were doing. And getting yourself killed isn't to be ignored with a "jeeze".
JerryD(upstateNY)
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Who would have thought that construction discussions could become heated? Thanks for the advice all. I'm sure I'll have more misc questions in the future regarding the project. I'm fully expecting to have to contract out various labor, and make local acquaintences in the industry to guide me down the right path and hopefully teach me something. This is in the early planning stages and I'm still learning the basics of concrete construction. I'll probably start construction in a year. Anyway, have a good Friday and weekend.
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snipped-for-privacy@gmail.com wrote:

Either works.

36' high walls? I think you have a bigger reinforcement issues than just how a partition ties into the exterior walls.

It's not clear where you are, what the design loads are (wind loads on a 36' high wall can be extreme), and what the intended purpose of the building is, but you should get some professional assistance for the design.
R
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You have no idea what you are getting yourself into. Another example of "you have to know a little about something to know you don't know anything about it". First, you will need an engineer to draw up the specs so it will stand up for more than a week. Second, the town you live in, will want to see a print with an engineer's stamp on it before they let you build anything. Third....Thinking you can build 36' high block walls on your first attempt to put up a block wall is crazy. If you ever get the walls half way up, the wind will blow the walls over and kill you.
snipped-for-privacy@gmail.com wrote:

--
JerryD(upstateNY)



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