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Alternatives for Parging

Saint in the City

Yes, I already mentioned bond beams.  Not the question.

Feb 17, 15 8:32 pm  · 
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awaiting_deletion

JeromeS at home on backup, but yeah will post a few later this is evening. On way home from work....

Feb 17, 15 8:32 pm  · 
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awaiting_deletion

Saint, code violation? Which one and why? Interested.

Feb 17, 15 8:34 pm  · 
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JeromeS

^Saint

R606.6.1 Pier cap.
Hollow piers shall be capped with 4 inches (102 mm) of solid masonry or concrete, a masonry cap block, or shall have cavities of the top course filled with concrete or grout.

R606.14 Beam supports.
Beams, girders or other concentrated loads supported by a wall or column shall have a bearing of at least 3 inches (76 mm) in length measured parallel to the beam upon solid masonry not less than 4 inches (102 mm) in thickness, or upon a metal bearing plate of adequate design and dimensions to distribute the load safely, or upon a continuous reinforced masonry member projecting not less than 4 inches (102 mm) from the face of the wall.

This is from the International Residential Code, the governing code for NJ.  Chapter 6 is full of references to solid cap courses and conditions.  Likely this is the basis for this detail.

Feb 17, 15 8:44 pm  · 
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JeromeS

I worked on a Fire Station project in north Jersey.  The foundation system was designed as a self-supporting slab with grade beams on timber piles.  The garage portion of the building was a single wythe masonry wall tied with reinforcing to the grade beams.  The contractor had difficulty installing the vertical bars due to the sheer volume of horizontal bars across the top of the grade beam - In multiple instances vertical reinforcing was drilled and epoxied in place.

This solution met the approval of the Architect, Design Engineer, Testing Engineer conducting 3rd party inspections, and Local Code Official. 

 

I'm curious about the code violation also... 

Feb 17, 15 8:52 pm  · 
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awaiting_deletion

Thanks JeromeS, so it's not a code violation? Or am I misunderstanding Saint? I would be uncomfortable with a 'masonry cap block' in high wind areas where the house could actually lift...

Feb 17, 15 8:53 pm  · 
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awaiting_deletion

Yeah JeromeS, got it. In nyc done many drill, epoxy to slab and build CMU wall. I can't see how it would be a violation.

Feb 17, 15 8:56 pm  · 
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JeromeS

You may have to extend your anchor bolt length to get the required embedment with a masonry cap.  Also, its been my training that anchor bolts are not provided for uplift;  their job is to resist sliding.

In real wind design conditions you are taking other precautions with shear walls and floor to floor tie down to resist all wind forces; sliding, overturning and uplift.

I cant say whether its a code violation or not.  It is just my experience that in a Class I structure utilizing intensive design and inspection requirements it was approved.  Further the embedment wasn't even very much, only 8 inches as I recall using off the shelf Redhead epoxy.

Feb 17, 15 9:00 pm  · 
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Carrera

Well its both slide & uplift... try substituting an AB with a Hilt and you'll be asked for uplift calculations, if there is no uplift then why the "J" hook and bolt for that matter, so its up then over (excepting earthquake zones).

Feb 17, 15 9:29 pm  · 
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.dwg

Hi all, 

Glad my post sparked a nice little construction discussion. I'm learning a lot about CMU and foundations in general. Just wanted to clarify, before people start a debate about what the OP first asked... I am practicing in Canada. I am building a house addition. This is for my own house. There will be a basement below. I have structural drawings for the city permits and I will be using vertical reinforcing in this cmu foundation. 

Anyway, I am using CMU only because of costs. Not for aesthetic reasons. I know CIP concrete is better, stronger, more stable, doesn't leak as much, and looks better. I will be applying waterproofing dimple board and membrane on exterior face of foundation below grade, as per normal practice. I also rarely see CMU block used for residential construction these days and I've detailed foundations for many projects with CIP concrete. Actually all recent projects have all been CIP. Hence, my lack of much knowledge about how to detail a CMU foundation. 

I am now leaning back towards CIP concrete because it's just so much easier to detail! My dimensions won't have to stick to 16" increments either. And I live in an urban area where many cement trucks come through for other new construction projects in the neighbourhood. I have decided to maintain my details with CMU in my drawings and have a discussion with my GC about what method would work best for the access that we have on the site (it's a rear addition with a 2.6 m driveway for access.) And also if it really will be about the same costs as CIP. 

The method that I've detailed at the bond beam under the sill plate is to have two rows filled solid (maybe overkill) and top the bond beam with a 4" solid block for the stem. It is a 12" ground face CMU that I'm using. The sill plate will be 8" wide.

Anyway, when you're a poor architect trying to design your own house, I think we as architects have the benefit of knowing how to entertain different building methods to lower our own costs. We are lucky we at least know what questions to ask compared to a 'normal' homeowner... 

So yes, I might actually be off the the races soon and use CMU and silane-siloxane spray sealer (which I've done a lot of research on including calling manufacturer) if that is what will give me the look I want, the performance I want, with the price I can afford.

With that said, anyone have any feedback about the cost of using cmu vs. CIP for foundation? I'm look at about 19'-6" x 15'8" c-shape foundation extending from the existing back wall. (I'm sure this will open up another whole can of worms! Ready set go!)

Feb 17, 15 10:51 pm  · 
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Carrera

Forgot. Your building this for yourself? Well in that case forget the anchor bolts (LOL). Surprised no one has brought up ICF's....the largest manufacture being  in Canada. Cost depends on market and what's more common in your area, I'd price it both ways..Planning a cottage for myself with a wood foundation

Feb 17, 15 11:24 pm  · 
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.dwg

A friend of mine mentioned ICF to me too. He did it on one of his projects recently. 

I don't know too much about them at the moment. Is it accurate to assume that you won't need shoring for ICF if you're close to the property line? 

Feb 17, 15 11:33 pm  · 
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awaiting_deletion

thank you Carrera!  the 'j' shape point makes far too much sense ;)  it can't move over if it ain't moving up....

@.dwg

are you or how are you tying the c-shape  foundation into the existing foundation?

how's the soil?

my concerns for CIP would be it's monolithic and if there is any subsidence the tie-in or joint at the base building would be where it would fail - most likely.  if you go CMU block, it will fail incrementally, like step cracks.  both painful to deal with....but step crack easier to deal with in my opinion.

how's access for the pour though?  it may be easier to move block to the rear with a 2.6 m driveway.

cost wise, it sounds like CMU....

@JeromeS...this is the best i could find for referenced project without posting too much etc...the money sketch was done in about 2 minutes after a lot of discussion between GC, me, and an out of the box thinking engineer.  I figured that's better to show than the final drawing.  also, there are a zillion factors that fed into the sketch decision (like our OP's issues), so I can guarantee this isn't a copy paste detail and may never work anywhere else...

if you look bottom right you see the future base of column  indicated by the rebar (aligned with eventual additional slab).  the black is old school wp'ing/dampproofing on the original house block and the grey block is the new...

this was a far better option than drilling 66 helical piles!

Feb 17, 15 11:37 pm  · 
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JeromeS

Ok- so it was a continuous footing, underpinned in segments.  I thought it was pier footings and was wondering how you supported each one and poured underneath each...

Feb 17, 15 11:58 pm  · 
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.dwg

@Olaf Design Ninja_ Thanks for the questions. The new foundation will be doweled into existing with 15M (16 mm), 24" long rebars @ 16" oc set in the grout lines. It will be embedded into existing for 6" with epoxy. Maybe I should also add, there will be underpinning involved in this project. The new foundation level will be matched with the existing level. Do you think this will still risk failure? Existing is also cmu, if I haven't mentioned already. 

Nice drawings! I love hand sketches. 

I have a feeling that I'll be going with cmu, that's why I've decided to leave the details as I have it. I'm having problems with the 16" increments though. It's killing me! I have an extra 3" for one length of this c-shape plan. Do I have to eliminate and make it a perfect 16" increment?? What to do in these cases?? 

Feb 18, 15 12:00 am  · 
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.dwg

OK I may have found my own answer on another forum, for those who wanted to know: 

"I laid blocks for a number of years (younger days) It was easy to work to any dimension that was called for. You could "lose" a little buy making the head joint a little tighter or by cutting off the "ears" of the block. If you just had to gain an inch in let's say 15' or 20', you would just open up the joint a little. If you needed three or four inches to gain we would use cement bricks and lay either the 2 1/4" or 3 5/8" way and adjust from there accordingly, whichever way was needed. If a brick was used it was counted the same as a block as far as cost. If we could "tighten" up the row to get the correct measurement there was no extra charge. The bottom line was the measurement was whatever the prints called for. A good mason has no trouble adjusting the measurement and the cost wasn't all that great. (Unless it was a "HUGE" project and then what's a few hundred dollars) Odd angled corners is what use to really drive up the cost-----much more then a odd length wall."

Feb 18, 15 12:35 am  · 
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Carrera

Good case for learning to build before learning to design/draw. Dowling? Bond beams? With light frame construction there are few concentrated loads... ever look at a framed house... its like a spider web of loads... add to that the sheathing and the loads bridge and scatter more.... its all overkill with the only real enemy being soil.

Feb 18, 15 1:02 am  · 
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shellarchitect

go to sleep carrera!

Feb 18, 15 8:29 am  · 
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Saint in the City

Jerome, you're citing the wrong IRC section in your 8:44 post -- which doesn't apply to what was the question at hand -- really not exactly sure what you're after now.

But anyway, the IRC 2012 defines anchorage along the top of foundation walls:

---------------------------------------------------------------

 R403.1.6 Foundation anchorage. 
Sill plates and walls supported directly on continuous foundations shall be anchored to the foundation in accordance with this section. 

Wood sole plates at all exterior walls on monolithic slabs, wood sole plates of braced wall panels at building interiors on monolithic slabs and all wood sill plates shall be anchored to the foundation with anchor bolts spaced a maximum of 6 feet (1829 mm) on center. Bolts shall be at least 1/2 inch (12.7 mm) in diameter and shall extend a minimum of 7 inches (178 mm) into concrete or grouted cells of concrete masonry units. A nut and washer shall be tightened on each anchor bolt. There shall be a minimum of two bolts per plate section with one bolt located not more than 12 inches (305 mm) or less than seven bolt diameters from each end of the plate section. Interior bearing wall sole plates on monolithic slab foundation that are not part of a braced wall panel shall be positively anchored with approved fasteners. Sill plates and sole plates shall be protected against decay and termites where required by Sections R317 and R318. Cold-formed steel framing systems shall be fastened to wood sill plates or anchored directly to the foundation as required in Section R505.3.1 or R603.3.1. 

-----------------------------------------------------------------------

This code section counters the statement  "You could even drill and epoxy if you wanted to..." on the 4" solid unit as you had suggested.

Obviously, I never said that epoxy connections are ALL code violations, but you can't epoxy into solid units -- even those thicker than your 4" -- to anchor sill plates.

Feb 18, 15 9:42 am  · 
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Saint in the City

I also just realized that I really don't like the word parging.  I was acually hoping that the thread was about finding an alternative to the word parging.

Feb 18, 15 10:28 am  · 
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awaiting_deletion

@.dwg. I think as Carrera said soil is your real enemy. Not sure how long your house has stood there and if there are water table issues or erosion and your soil. I am guessing you probably didn't do any boring tests or STP tests or have an old one or a general feel for your soil conditions?

Feb 18, 15 5:09 pm  · 
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awaiting_deletion

I mean SPT.....not stone temple pilots, although that could also make sense.

Feb 18, 15 5:10 pm  · 
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gruen

Hey Saint, why is epoxy into solid masonry a code violation (for sill plate anchorage)? My read is that it needs to be anchored 7" min w/a 1/2" bolt, doesn't say how that is achieved. I know epoxy joints are stronger than other masonry anchors, not sure how it compares to embedded anchors strength wise. I've certainly used epoxy into existing foundations. 

Feb 18, 15 6:16 pm  · 
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.dwg

@Olaf Design Ninja_ No water table issues on the surface, and the house has been sitting here for more than 70 years. No large cracks in the walls etc. Next door neighbour has a one-storey extension (no basement) and two doors down also has an extension. Not sure if this means anything but it seems kind of overkill to do a bore test for a small residential extension. At least that's not common practice here. I've certainly worked on residential projects where terrain on a ravine called for a geotechnical consultant. But others where we had water table issues didn't have any, except for a storm water management consultant. 

I know that will be one of the first things that will come to mind when the digging begins. Thanks for mentioning it though, because I think it will definitely be critical path for all foundation decisions. I know that the new basement will be the first thing to be deleted if the overall budget is too high. If that's the case, I'll still use the silane-siloxane spray method for the above grade block, but will waterproof a crawl space instead. 

Feb 18, 15 7:41 pm  · 
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awaiting_deletion

.dwg. based on what you said sounds good, but don't hold me to it (I'm licensed in US states only). And I am going to start calling them stone temple pilot tests....

Feb 18, 15 7:49 pm  · 
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JeromeS

@Saint

i didn't note those sections with respect to the anchor bolts.  There was a question about why a wall would be detailed with a solid cap.  Those sections of the code reference locations where a solid cap is required.  For the variety of beam and support conditions you sometimes find in residential construction and for consistency of construction- we always detailed a solid top course

 

@greun

There is nothing wrong with the epoxy.  As long as you achieve the required ts of the section: grouted core, min. embeddment etc.  you might have to provide calculations in lieu of relying on the prescriptive elements of the code

@Saint

i never said epoxy ing into a solid cap was sufficient. My point was that epoxy would allow you to lay out the anchor bolt irrespective of a open cell in the top of the block 

Feb 18, 15 11:10 pm  · 
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Good case for learning to build before learning to design/draw.

You'd think this would be a basic part of the education. 

Feb 18, 15 11:32 pm  · 
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Carrera

How many of you have drawn-in a steel clip angle on a block wall to hold roof decking instead of adding another bar joist.... thinking you were saving money? Easy, zip-zap wall angle, done.

In early years I took a job with an architect turned GC and he put me in a trailer to run a restaurant job. Bar joists came, ironworkers put them up and left in a matter of hours... but no deck... wondering a truck pulled up from the steel fabricator and the guy said "got your clip angle, need help getting if off the truck" (no ironworkers).... Jesus Christ it was in 20' sections, almost impossible to carry. Next day a sole ironworker came back with a manual fork lift, ladders and impact tools... this guy worked a full 8 hours bolting these 2 angles to the wall.... the whole job was shut down waiting for this guy.... then the next day the crew came back to finally erect the deck...3 days work for a 1 day job because of that bright idea... had drawn plenty of angles up to that day but never drew one again.

Feb 19, 15 12:58 am  · 
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awaiting_deletion

Nice story Carrera! And JeromeS I see what you thought I said now and that would of been fun or re-goddamn-diculous.

Feb 19, 15 8:08 am  · 
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we always detailed a solid top course

(One) problem with block is limited lateral strength against heaves (not the kind you get from eating feng shui). Filling the top course solid provides grip for an anchor bolt to a single block and nothing else.

In practice filling the top course was done with newspaper or whatever trash was on hand, most of which was stuffed into the top course which was then parged with a bit of cement so that it looked solid.

Feb 19, 15 9:22 am  · 
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Saint in the City

Agreed on the lateral strength of CMU, as opposed to poured in place.

As for the anchor bolts only affecting the top course --  better design is to go past the code.  Wire the anchors to the rebar verts.

Yes, I realize code may not require the verts.   Up to you if you want to skip them if not required per the letter of the code.  We call for them anyway, for many reasons. 

Feb 19, 15 10:44 am  · 
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