Im expanding my 28' wide single story composite shingle home. I want to come out perpendicular off 1 plane of the roof to expand master bedroom, and then remove the wall. The foundation is crawl space with peer and beam foundation. Im installing an 18' 14x3.5 psl beam above the wall being removed that will have the 2x6 rafters and 2x6 ceiling joists nailed to the face. Im in sf bay area with no snow load. The beam will rest on two opposite 90 degree corners of the foundation peer. My question is do i need to reinforce the peer foundation at those corners to accomodate the load created at the peer and beam foundation corners as a result of removing the wall under beam. I believe there may be 6' concrete columns under the concrete beam at the corners.
You need to go to your city building department and pull a permit. They usually have a code engineer who tells you what you need to do in detail.
If your soil is ok and you are not in a hillside, it should not be too complicated.
They expect not only foundation and columns modifications, but also a plan of addition of some shear walls or some kind of lateral load resisting premanufactured wall such as "Simpson Shear Panel" with its required new foundation to remedy the loss of lateral support due to removal of your wall.
You may ask at the plan-check desk for their Type-5 remodeling handouts and approved test data sheet on the types of these premanufactured shear walls and their wind and seismic ratings.
Or else they ask you hire an engineer, and they may even ask you to upgrade the existing home up to code if the addition is bigger than their limit which triggers code upgrade.