a wrote:

Just redoing the front porch - ~5'x6'wide. It's only ~3' high and
there are cement steps. It's rotted all to hell, but my only
question is what's the common wisdom on attaching a ledger to the
foundation (really hard - poured in 1954). The 2x6 that's there is
only nailed - and those nails are badly rusted - some right through.

I bought some 6" galv. lag bolts (3/8) and planned on using lag
shields. I have since done some looking and people seem to be weary
of them.

Use a hammer drill to make new holes for the lag bolts and shields.
Rent one if you can't borrow one. The holes will take 20 seconds
instead of 20 minutes each. Your back will thank you.

You can also use epoxy to anchor the bolts.

Don't overtighten the bolts. You might crack the concrete.

Use pressure-treated (PT) wood for the ledger.

Use hangers for the joists.

Use double-hot-dipped hardware to fasten to PT wood. Don't buy the
cheap electroplated stuff. The zinc coating is too thin, and you'll rub
most of it off going into the wood.

Put a z-flange (also called a drip cap) on top of the ledger so water
doesn't run behind it. It will last longer.

Make the porch slope away from the house about 1/4" per foot so water
drains off.

--
Steve Bell
New Life Home Improvement
Arlington, TX