When the rebar started appling in poured concrete footing and foundation

[Peter Louis]

It just came into mind when I saw this crack on this foudation. It looks like shrinkage crack with a little settlement. I don't think it is structural. But if there is a rebar there, is it possble the crack is bigger due to the rust?

Also, when was rebar applied at footing & foundation?

Thanks

[John Kogel]

From the History of Concrete and Cement. Google it."Reinforced concrete was invented (1849) by Joseph Monier, who received a patent in 1867. Joseph Monier was a Parisian gardener who made garden pots and tubs of concrete reinforced with an iron mesh. Reinforced concrete combines the tensile or bendable strength of metal and the compressional strength of concrete to withstand heavy loads.

Joseph Monier exhibited his invention at the Paris Exposition of 1867. Besides his pots and tubs, Joseph Monier promoted reinforced concrete for use in railway ties, pipes, floors, arches, and bridges".

We can't be sure how rebar was placed in a foundation wall or whether it was used at all. That is why we need building inspectors to monitor the different stages of construction.
AFAIK, rust will not be a problem unless the rebar is exposed to water and air. I believe the crack comes first, then damage to rebar will occur if there is moisture.

[Peter Louis]

Thank you, John.

Poured Concrete foundation was started about 100 yrs ago in the lower mainland, whch was quite expensive at that time. I do not know rebar was applied at that time or not. When was rebar started in local construction, any thought?

[John Kogel]

Well-built houses had rebar in them from day one. Crappy cheap houses had old bedframes and water pipes thrown in there. Sometimes just in the corners. ;)

When was the building code adopted in your area and when did the authorities start to inspect buildings under construction? That is when you can be fairly sure there is rebar in the concrete.

[Gunnar Alquist]

Hi Peter,

Around here, rebar was used in the 1950s, but exactly when, I'm not sure. I probably have an old UBC, but not handy.

[Mark Reinmiller]

It just came into mind when I saw this crack on this foudation. It looks like shrinkage crack with a little settlement. I don't think it is structural. But if there is a rebar there, is it possble the crack is bigger due to the rust?

Also, when was rebar applied at footing & foundation?

Thanks

I'm a little confused by what I am seeing in the photo. It looks like the bottom of a FW near the floor, but is that stucco above the concrete? It appears to be a shrinkage crack if I'm seeing the photo correctly. In some areas there is still little or no rebar put in foundation walls or footings.

[Tabb Jensen]

You will never know - if rebar is in there, unless you tear it apart. Caring pros put metal into almost any major concrete work. Short cutters and people trying to save a few bucks did'nt and do not. My father always did - and his concrete stood the test of time. When he aged - he hired contractor's to build a new house and driveway. They did not put metal in a curved/sloping part of drive. He told them - The concrete (in his day) would crack without it. They said new concrete doesn't need it. They laid the concrete - it cracked badly. They had to come out and replace it - on their dime - they put metal in it that time. My pool deck 40' x 60' that I had laid - has it - I insisted, I paid for it, and I was there to ensure it was put in. My deck after years is still in great shape. -- Handyman Tabb

[S Young]

if rebar is in there, unless you tear it apart.

Try a metal detector, a good store will point you to one and may rent it to you.