Q: Surprisingly the foundation company sees no settlement in house. possible?
A: Absolutely possible. Foundations can crack for any number of reasons, including soil erosion, water expansion inside the concrete, rusting rebar, improper pour, no rebar, earthquake ... the list of possibilities is endless. Concrete can crack yet not move. It's the movement that causes settling, particularly if a foundation cracks and then only one section moves. If the cracks are still tight top-to-bottom with no deviation side to side or vertically, then you have simple cracks with no movement. Ironically, a house can also settle in a number of ways without the foundation cracking in any way.
Q: The cost of repairs are 70k . Isn't replacing the whole foundation better?
A: Depends. Without knowing the address and personally assessing the situation, we'd just be guessing. Ask the company that did the foundation repair estimate how much an entirely new foundation would cost. That will tell you right away which option will be best.
With any cracked foundation, there are two levels of concern: first of all, figure out what caused the crack and make sure the cause is stopped/remediated. This will make sure the condition will not continue or progress. Second, repair the existing damage so that the structure is once again structurally secure. Once the cause is determined, then an assessment of whether or not an entirely new foundation would be necessary can be undertaken. Frequently, once the problem that lead to the cracking is solved, then any subsequent repairs are adequate and, in most cases, FAR cheaper than replacing the entire foundation. Frequently, it's the cost of repairing the cause that is more expensive than the actual foundation repair. It could mean extensive drainage systems, piers to stop soil movement, retaining walls ... the list is endless.
Q: The work involves replacing the fracture site in the house. Should the home be fixed or bought as it is?
A: That depends on you, the seller and the market at the time you buy the home. If this home is in the 94539 area code, there is good chance there will be many interested in the home regardless of the foundation issues. That could mean multiple offers - which could mean "AS-IS". If there are no other offers, you can try to strike a deal with the seller that meets both of your needs and addresses the problem to your satisfaction. In a seller's market like the one we find ourselves currently, mot sellers want to take their money from an "AS-IS" sale and run from issues like this as fast as they can.
If you don't know what a cripple wall is check out this link and give yourself a quick education.
We've been doing foundation retrofitting for almost 3 decades and that includes anything and everything from cracked slabs to total foundation replacements whence we literally block and crib a home up over our heads, remove the existing footings and pier posts, excavate, form up and pour a new footing and install new post and pier assemblies.
To just block and crib a structure that size would cost close to $10k. Then you would need to disconnect all your utilities and infrastructure and reconnect if not reroute entirely. This could cost anywhere from $2500-5000 if there are no complications.
This entire process could cost anywhere from $125-200 per lineal (perimeter and interior footing walls) foot just for the new footings and $100-250 for new post and pier assemblies. So if you have a 1000sf single story home with that's 20x50 you'd be looking at 140 lineal feet 12inx12in at an average of $150/lf or approx 20k for the footings and just guessing that you'd need about 20 new piers at $150ea for another $3k plus permits.
Then you add your French Drain in around the perimeter of the home at approx $25/lf for another $3500. Throw in the clean-up and debris removal for another $2500 and you're close to $30k. But rememeber that's a rectangular 1000sf California Ranch. If you have a two story or split level home you'd be
So on a 1000sf home you could easily spend $35-40k and thats if you don't have any other issues i.e. sloping lot, boulders and tree trunk removal, utilities in the way that would need to be stubbed out and reconnected.