Deck flashing question

Is it ever acceptable to attach the deck to the home without removing the vinyl siding?
The vinyl siding was not removed, the deck was butted tight against the vinyl and bolted directly to the home. No flashing.
Also, what is the recommended distance between lag bolts?

Thanks in advance.

Does this help?

Was there moisture barrier behind the siding?

Steve, in short no. The vinyl siding needs to be removed, then the ledger board gets installed, then the flashing which should be copper so it doesnt react with the new treated lumber. Then the decking and then the siding can go back on.

I usually put 2 3/8"X3" lags with washers in every other bay.

Aluminum works, right?

Not in my opinion. I suppose one could mount the ledger tight enough to crush the siding but it is not right.

It depends on the loading.
See page 9 of this:

Joe, A very big NO! aluminum flashing will react to the copper treated wood and the chemical reaction will break down the aluminum within months, this will cause the flashing to be ineffective.

Think of copper valley flashing, if you used a aluminum roofing nail to secure the flashing down to the roof it would start eating away at the copper within days. All or most pressure treated wood is now rated ACQ which is Alkaline copper and comes with the brand of Nature Wood, in my area anyway. You will find some treatments that uses Borate in it for pest infestation.

I should also add that all fasteners that penetrate the copper flashing need to be copper as well, hope this helps.

Thanks everyone.
Carl thats a great reference. Thanks