Jeff … as a licensed builder, licensed GC, and a code certified E1, B1, P1 & M1 … I’ve done construction stage / progress inspections since about 1995. We are NOT code inspectors and have no authority to enforce code, but a competent home inspector will know many major code requirements so when he / she sees something thats out in left field they can recommend further evaluation by the applicable party. Below is a comment I made in a report on a Stage Inspection about 26 yrs ago. After the head engineer read my letter and went out and looked at the site, he RED TAGGED the construction and required MAJOR changes. The builder, his engineer and their Realtor were LIVID. My clients were VERY happy campers and their niece was an investigative reporter for a local TV station. I got a LOT of future PR out of that.
Dear XXXXX:
On Thursday (3/8/98) at approximately 4:10 PM observations were made at the above referenced location. The site faces generally to the east and the temperature was 46 degrees. At the time of the 1st examination the lumber and steel rebar for the footings forms were in place. The concrete for the footings and the steel I-beam support poles (column pads) had not been poured yet. One workman was still on site and indicated they had their “pre-pour” code inspection today, it passed code and they would start pouring concrete, etc tomorrow. The formwork and rebar appeared to be in overall proper condition. It was noted however that at the south / rear of the site, there was a heavy limestone ledge. At this location the footing formwork was not as deep as typically required by most building codes and good building practices. In this area and on normal load bearing soil the typical footing will be 8” deep by 16” wide. The footings at this area appeared to be about 5” x 16” and the rebar had been inserted into holes drilled into the limestone. The rebar is then bent at a rounded 90 degree angle and will become part of the concrete footings. This procedure is done to “tie” the concrete footing to the stone and prevent moving.
This is a commonly seen practice and considered an adequate alternative by most local engineers. There are however several questions you should raise with the foundation design specialist that is overseeing and designed the foundation for this site (The City of XXXXX requires either an architect or engineers design). In the past when I have run into this type of site condition, the soils engineers that I have worked with have often:
(1) installed epoxy into the holes in the stone prior to placing the rebar (locks it in place);
(2) either designed differently sized footings for the different soil bearing capacitys and areas present at the site; drilled down to bedrock at the clay areas and poured concrete piers; or overdug the stone, removed it and then placed compacted fill soil in its place; or raised the foundation – the end purpose of any of these actions was hopefully so the whole foundation was bearing on the same type material OR load carrying capacity and should therefore move together rather than differently.
In reading the letter you faxed to us this afternoon from the builders engineer (XXXXX), he has stated that a foundation placed on clay and limestone will have a tendency to settle and move differently because of the different load bearing capacity of the 2 materials. This is absolutely correct. He then suggested placing extra steel rebar into the footings & walls (this strengthens the concrete and helps hold it together). Based on the information in his letter, I don’t understand however, how Mr. XXX feels that placing more rebar in the concrete by itself will prevent differential settlement or movements of the structure due to the different load bearing conditions that he identified. You should have him clarify this for you in writing.
Also I would recommend you call the Code Administrator for the City (SSS TTT) who is a licensed structural engineer himself and tell him you are having me monitor your construction (he knows who I am), tell him I disagree with the builders engineer and request he review his own code inspectors inspection.
My recommendations or comments are not intended to be criticisms of the building, but as professional opinions regarding present conditions. Use them to help you assist your builder.