Need alternative to wide floor joists in small spans
We need to have installed a new physical roof on our home due to the short life of the existing flat roofs that are leaking. Since the kitchen roof is flat and actually drains towards a 2nd floor room, we decided to replace it now and also expand the kitchen by 5 feet into an existing storage area beneath the 2nd floor room.
The kitchen wall we are moving back is the original house's outside wall and supports the wall of that upper 2nd floor room. The architect is using 2 x 10 P.T. Ledger with two 3/4" dia thru bolts @16" OC that will hook up with our existing dimensional lumber floor joists to span the 5 feet to the new 2nd floor room support wall.
The problem is these wide joists will reduce the 24" minimum crawl space we requested, to 18". Our sewer line runs under that area and we will have to put in plumbing and electricity next year or so when we renovate the kitchen cabinets/etc. So in effect he is making future access to this area very difficult, by using an industry standard and not future problems in this area.
We have pointed out several oversights in his drawings and he is no
longer being as proactive. For example, we asked that the access to this
area be increased from 18"x24" and he came back and gave us an even
smaller opening, 18"x18". I guess he caught one of his own oversights
We asked for an alternaive method of support for this area and never received a reply so here I am.
What other alternatives are available to support this 12'X5' area that will provide at least 24" of clearance? Is there something that is 4" deep that will comply to code? See image.