Advice needed for Cold Joint in a 47 year old house.

Hello friends,

Our bid to a 47 year old house in Fremont CA, was recently accepted and we are in escrow. Turns out that there is a cold joint in the foundation (pl see attached pic). The cold joint is visible along the entire exposed side of the foundation wall and so the Structural engineer believes it is all around the 4 sides. We already got it evaluated by Structural engineer who has recommended that we go for

  1. New anchor bolts at perimeter footings.
  2. Add plywood at cripple walls between the floor and footing

I have a few questions, for which I would really appreciate your advice:

a) How common and worrisome is this? If this indeed happened at the time of house construction then it has not affected the house. But then can we expect to see this problem in other identical homes in the neighbourhood?

b) If we go with the recommendation of the Engineer, will their be additional damage to the existing foundation, when the bolts are added?

c) The property is in Fremont CA, (close to Hayward Fault)- so we are wondering if structure has less capability to withstand tremors than other similar properties that do not have this issue.

d) The previous owner says he was not aware of this issue.
Thank you very much. Though we have the assessment, we are worried that this might lead to something big.

Thanks

http://www.nachi.org/forum/C: emp\cold-joint.png

Hello all,

I was hoping some one from this list would offer their wisdom!

I missed to add that as per the Structural eEngr recommendation we will only be rebolting the accessible portion of the foundation from the crawl space. The Engr is not able to tell if the entire section of the cold joint is well reinforced with the bottom layer… He says using ultrasound etc will be too expensive and without reaching out to the original builder it is hard to determine. We are trying to get the builder details from city records.

Based on the other cold joint related postings on this forum, it might not be bad structurally. I am just worried, since it is on all sides of a 30’*30’ approx dimension area…

Your advice will be most appreciated to give me peace of mind.
Thanks
Deepa

The home is 47 years old and has not shown any problems yet. You have had a structural engineer evaluate and provide a recommendation for repair. I would suggest that you ask your questions of the engineer that developed the “fix” as they should be most familiar with your areas seismic activity.

Have you talked with any neighbors about their foundations?

I have seen many just like this some older then yours .
.Seems to me like nothing has changed in 47 Years and likely nothing will happen in the next 47 years .

Jeff & Roy,

Thank you for your responses! Asking in the nhbd is a great suggestion. We were doing that via the realtor but this is a better idea.

Roy–Surprisingly both the structural Engr and the realtor have not seen Cold joint issue in their practice. Atleast quite uncommon is what we were told. It is good to know that your experience is different.

Thanks!
Deepa

Agreed Roy and it is the reason I did not comment either. Foundation cold joints are only a problem if they are starting to fail. Have yet to see this in a House construction but I have seen it in a garage construction.

Non issue. I find this on many homes and it is of no concern whatsoever. That’s just how the house was built.

Add the shear-paneling and bolt plates to upgrade the foundation, but don’t be concerned with the cold-joint.

Thank you Kevin & Jeff P.

Is there any way to tell whether the entire section of the cold joint is well reinforced, without opening up the walls? Currently we plan to bolt only the side that we can easily access from the crawl space area. Opening up the walls on the remaining 3 sides, will be expensive and daunting.

Thank you all for your time and attention to this.
Deepa

There’s no easy way to verify the reinforcement of existing concrete.

Thank you Jeff.