For those with Inachi Deck Inspection Book, should recommendations be made to deem this ledger attatchment unaceptable;
When the 2009 IRC says it is one of the accepted methods?
Washer spacers is widely used around here and people frequently ask me if this is the way.
I usually tell them that my preferred method is the lag screw method with flashing.
I just want to make sure that these calls don’t get anyone in trouble.
Should not be called out as a defect.
But in lieu, just a recommendation that differs from what is acceptable to the minimum standards of the code.
Marcel, I virtually never see the “washer/spacer” method. Personally I never cared for it. My preferred method is the lag/flashing method also. Thanks for the reminder. It’s been a long time since seeing the washers. Good reminder.
What bothers me more is when attached to brick veneer you are not supposed to over tighten the lag bolts which to me is almost the same deal as the washers in that you are not getting as secure a connection to the wall.
Am I wrong to think that ?
Although allowed by the Code, they also recommend adding a deck beam closes to the connection to take care of exactly what you are saying Bob.
So pretty much, it is only holding the deck stable and the deck is basically free standing. That is in the 2009 update also.
Must be why I see the words below in Prescriptive Residential Wood
Deck Construction Guide
Based on the 2006 International Residential Code (PDF)
PROHIBITED LEDGER ATTACHMENTS
Attachments to exterior veneers (brick, masonry, stone)
and to cantilevered floor overhangs or bay windows are
prohibited (see Figures 17 and 18). In such cases the
Figure 17: No Attachment to or Through
Exterior Veneers (Brick, Masonry, Stone)
deck shall be free-standing (see FREE-STANDING
DECKS).
Unless the washers are hot dip galvanized and protected with flashing
corrosion will occur and therefore regardless of the “2009 building code” rust will penetrate all the way through to the hot dipped leg screws or bolts.
Here we go again with the recommendations that will compromise safety.
That is exactly why the Code is the bear minimum of standards.
I would never recommend that attachment.
And that is why Inachi did not either in their book of How to Inspect Decks.
Now we know the whole story.
Well typically when someone wins a prize, I let Jeff Jonas show them what they won, But my recommendation would be to just be content with the fact you won. :)
Speaking of decks I was talking to a contractor today and he said one of the city inspectors is recommending new decks to have 4 inches from the center of spindle to the center of the next spindle. That is why I see some new decks with spacing less than a 2 inch ball can fit through.
Say it isn’t so.
I think he just doesn’t know or miss read the RBC.
Talking through his hat, but the AHJ has the final word. I would ask to see the written code or amendment to the code that he is basing his decision on for the jurisdiction he is in.
The reasoning is quite simple: Using a lag bolt to hold a ledger board away from the band joist is, in essence, using the lag bolt as a cantilever. Lag bolts are not designed to be used as cantilevers. They simply don’t have the “shear” strength to be misused like the IRC depicts.
Too few washers… and the washers simply squish between the wood leaving no space for water to pass. At the point where you have enough washers to create space between the wood… you’re relying on the cantilevered shear strength of the lag bolt to carry the load of the deck and it’s occupants.
I agree Nick, I just wanted to point out the discrepancy between the Inachi book and the Code as written.
So coming across an installation with the washers, we can’t call it a defect because it is allowed by Code. Correct?
