join new crawl space CMU footing/foundation to existing CMU basement wall

07-26-2010, 11:57 AM	#1
CapeCod153 Member   Join Date: Jul 2010 Location: Flemington, NJ Posts: 70	join new crawl space CMU footing/foundation to existing CMU basement wall Hello everyone. I am a new to this forum but it looks like an excellent resource. I am starting an addition for a 1 ½ story capecod that I own. The capecod was moved about 10 years ago so the foundation/basement is “new” and was constructed with 12” CMU block and 9’ high ceilings. I do NOT have any construction drawings for the existing basement. The addition I am adding will have a crawl space under it and, therefore, the addition’s new concrete footings and 8” CMU block walls will be much higher than the existing footing. My questions: 1) Do I need to tie the addition’s new concrete footing to the existing CMU walls? 2) If so, how is that best done? I do not know if the existing walls are grout filled or how they are supported. My research has revealed limited recommendations. My thoughts are to simply drill 2-3 holes into the existing 12” CMU walls where the new concrete footing will butt against it and epoxy/grout in rebar. To do this I assume I drill the holes, insert the rebar into the holes and then fully fill in the penetrated 12” core(s) with grout from a larger(s) hole above in the same core(s). Then I simply pour the new footers for the addition’s CMU walls. 3) Do I need to use a double "L" #4 rebar rod as the connecting rod or are the rebar ridges on a straight rod enough since I am simply trying to prevent different vertical shifting? 4) If the new footing is tied into the existing CMU walls do I have to tie some or all of the new CMU courses into the existing CMU walls, too? 5) If so, how many courses should I tie into the existing CMU wall (i.e. every other course or top and middle course, etc.)? Thanks! Keith

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07-27-2010, 10:58 AM	#2
CapeCod153 Member   Join Date: Jul 2010 Location: Flemington, NJ Posts: 70	join new crawl space CMU footing/foundation to existing CMU basement wall crickets.....anyone?

07-27-2010, 11:11 AM	#3
47_47 Member     Join Date: Sep 2007 Location: Springville, NY Posts: 1,232	join new crawl space CMU footing/foundation to existing CMU basement wall Don't know answers to your questions, but someone will answer. It would help if you put in your location and frost depth if you know it. __________________ What we've got here is... failure to communicate. Some men you just can't reach. So you get what we had here last week, which is the way he wants it... well, he gets it.

07-27-2010, 11:23 AM	#4
CapeCod153 Member   Join Date: Jul 2010 Location: Flemington, NJ Posts: 70	join new crawl space CMU footing/foundation to existing CMU basement wall Thanks...located in Flemington, NJ and code requires footings to be 36" below grade.

08-04-2010, 08:35 PM	#5
Aggie67 Licensed P.E./Home Insp     Join Date: Dec 2008 Location: New Jersey Posts: 585	join new crawl space CMU footing/foundation to existing CMU basement wall Keith, If you get stuck, I do engneering for this sort of thing for a living. I'm in Branchburg. I'm doing calcs for a job right now for a house in Princeton. PM me with some contact info. __________________ To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.