Below are three drawings showing the current framing and two replacement options we are considering. We don’t know why there is ½ inch plywood on top of the 4x6 beam, but suspect it is to remedy a framing mistake. Only 1 inch of the 2x6 joists bear on the plywood, so it looks like the original builder added a 2x6 ledger to increase support. I believe the code required is a minimum of 1-1/2 inch bearing on wood.

Option #1 allows 2 inches of the 2x6 joist to bear on the 4x6 beam and Option #2 allows 3-1/2 inches of the joist to bear on the 4x6 beam. Are both methods acceptable or is there a preferred method?

In addition, the 4x6 beam is supported at the cement block retaining wall by a pressure treated 2x6 ledger secured to the wall with pins. Only 1 inch of the end of the 4x6 beam is supported by the 2x6 ledger and the beam is poorly toe nailed to the 2x6 ledger.

I looked in several framing books and I could not find any examples of supporting a beam at a wall with a ledger board. We are thinking of replacing the existing 2x6 pressure treated ledger with a new one mounted higher with 5/8 inch threaded rod and bolts. The 4x6 beam would be terminated in a Simpson HU46 hanger nailed to the new 2x6 pressure treated ledger with 1-1/2 inch, 9 gauge, HDG nails. Is this acceptable practice?

The damage from rot and powder post beetles to the framing in our crawl space was significant. Below is a picture of what was left of the triple 2x6�s that made up the girder that supported the center of our townhouse.

We spent the last two years investigating where the water was coming from and believe we have done all that can be done to eliminate the sources. With that resolved we moved on to rebuilding the foundation and framing in the crawl space.

Regarding end bearing for joist and beams. I found the following in Principles of Home Inspection: Systems & Standards.

Joists require 1 1/2 inches of end bearing, considerably less than the 3 1/2 inches required for beams. That's because the live load carried by individual joists is much smaller than the beam's load. Note: Some jurisdictions call for 3 inch end bearing on masonry. Check standard practices in your area.

Where joists rest on beams, best practice is to have the joist rest on the full width of the beam, rather than just 1 1/2 inches. Good practice also includes splicing joists that overlap from opposite side of the beam.

Based on the above I believe I should go with the following:

Since my last post we poured new footings and pilasters for the posts that will support the middle of the new 4x6 beam and floor joist. The new 4x6 beam will replace the existing 4x6 beam and �" plywood.

I would like to support one end of the 4x6 bean with a Simpson HU46 hangar nailed to the 6x6 beam that replaced the rotted triple 2x6�s. This will leave a �" gap between the new 4x6 beam and an existing 4x6 beam below.

The other end of the 4x6 terminates at a CMU wall. Currently it bears 1" on a pressure treated 2x6 secured to the CMU wall with corroded pins and washers.

I believe I have three options.

1. Remove the current pressure treated 2x6 ledger and secure the end of the new 4x6 beam in a Simpson HU46 secured to the CMU wall with Simpson Titen screws.

2. Remove the current pressure treated 2x6 and replace with another pressure treated 2x6 that is located 5-1/2" higher and secured to the CMU wall with expoxied 5/8" bolts, washers and nuts. The new 4x6 beam would be secured in a Simpson HU46 secured to the new pressure treated 2x6 with 1-1/2", 9 gauge, HDG nails

3. Remove the current pressure treated 2x6 and replace with a pressure treated 4x6 secured to the CMU wall with expoxied 5/8" bolts, washers and nuts. This will allow the 3-1/2" of the new beam to bear completely on the new 4x6 ledger as recommended in Principles of Home Inspection.

Comments appreciated.

He also said the revised framing is acceptable, but he wants me to add blocking under the 4x12.

Thank you to everyone who responded.