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If an old building has been poorly maintained, and water was allowed to penetrate the walls and damage some studs, exterior wall sheathing and finish, maybe some floor sheathing and framing.. does a repair have to comply with the Repair requirements of the Existing Building Code (Section 405 California EBC, for reference)?... ie. fall under the 30% trigger for substantial structural damage, or be evaluated to current code criteria

It seems like a substantial structural repair, is written to repair damage from an event.... not just deterioration.

It seems the 30% trigger makes sense for an event, because if an event damaged that much of the building, you should re-evaluate it... not just repair it to pre-damaged state. But, if its just deterioration... and there is nothing that indicates it has ever been damaged during a wind, seismic, or any other live load event... it seems repairing to pre-damaged state makes sense.

But I havent been able to find anything on it specifically.

If I do take the gradual deterioration as an event.... and per the definition of Substantial Structural Damage in the CEBC.... if the portions of the building which are damaged/deteriorated/rotted support more than 30% of the building.... say 50%... but you know it occurred over the last 20 years.... not five, as per the definition... would it meet standard to argue that that equates to about 13% in five years... so it still qualifies as Less than Substantial?

And if it does qualify as Less than Substantial... It appears it can be repaired, without a permit, to its pre-damaged state. Correct me if I am wrong.

RE: Repairs

If the building inspector is bald, he might not have so many hairs to split. Don't know what its like where you live, but most BIs won't argue about 5 yrs or 20yrs and don't care. They're far more interested in the 50%. What can you patch and paint in distressed finish to get under the 30% without looking like it was done yesterday, or ... you know you need a permit. Just go get it.

Statements above are the result of works performed solely by my AI providers.
I take no responsibility for any damages or injuries of any kind that may result.

RE: Repairs

@Dik: great infosheet, thanks for providing. well put together and thorough (like most of your contributions)

I'm not sure of the answer, but I follow a similar line of logic with your specific problem as below:
1. I agree that earth, wind, fire IS an event
2. I agree that the deterioration IS NOT an event.
3. Repairing deterioration would be a straight remove-and-replace UNLESS substantial structural components, or multiple components were damaged or missing, as noted in reconstruction. Discretion of inspector and engineer would determine this.
4. Life Safety would be the governing objective, above all. If during the repair, the exploration for damage exposed an insufficient beam (for example) over opening, I would be inclined in upgrading that.

The cutoff around here is generally in terms of repair cost vs. assessed building value in FIXED value (ie. $200k or $250k). A %(percent) cutoff also exists for total area of building, but this is a higher limit (67%, 75%, or sim).

RE: Repairs

I've been playing this game for over 50 years...and my experience is not 1 year x 50... I cannot overstate that substantial strength can be lost with little loss in weight or material... the cellulose, which provides the 'tubular' strength is removed (light weighing stuff) leaving the lignins which gives the decay the name 'brown rot'. I should have added that epoxy injection is often used for brown rot issues...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?


RE: Repairs


I'm not familiar with California codes, but a quick google search indicated that the California EBC is an adopted and amended version of the International Existing Building Code. I have a copy of the 2015 IEBC handy for reference, YMMV based on what year and amendments you need to follow.

In Chapter 2 Definitions, "repair" is defined as: "The reconstruction or renewal of any part of an existing building for the purpose of its maintenance or to correct damage." I don't see anything about an "event" in that definition.

"Event" is also absent from the definition of "substantial structural damage". At the end of the day, if a structure has lost enough capacity to reach the cutoffs in the IEBC definition for substantial structural damage, does it really matter if it happened over 1, 5, or 20 years? It's still substantial structural damage. It may take 20 years for a car to turn into a jalopy, but at some point its not road worthy and the time it took to get there doesn't matter.

The way I read the various repair sections is that you are often allowed to use the loads from codes in effect at the time of construction, unless the damage is the result of an event. If the damage was the result of wind, the repair needs to be designed for current wind loads. Damage due to snow? Need to design the repair for current snow loads.

I am currently involved in a matter where the damage was the result of a tree, so in theory I could use the loads from the codes at the time of original construction. However, the building is old enough to predate the local building codes, so I'm in engineering judgement territory.


RE: Repairs

I would suggest that 'to correct damage' would imply 'an event'. I don't know what the usage in those environs is, you might want to discuss this with the AHJ.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?


RE: Repairs


You sent me back to the 2015 IEBC commentary looking for more information and my position has evolved.

The commentary states, "Note that the definition deals with both repair as it relates to maintenance and repairs as they relate to fixing damage inflicted on a building for various reasons. More specifically, the replacement of stairs due to daily wear and tear is related to the maintenance of a building; whereas a wall hit by a forklift or damaged as a result of an earthquake would be considered damage as it relates to the definition."

So the commentary does make the link between damage and an "event" in this case a forklift impact or earthquake. I would say that long-term deterioration due to recurring moisture intrusion fits the maintenance side of repairs.

I still feel that if you lost 20% capacity in a beam that was supporting at least 30% of the structure (ie the beam in the center of most basements), then in the spirit of the code that is substantial structural damage regardless of how many years it took for that lost capacity to accumulate. If the lost capacity is due to deterioration, and not a discrete event, you don't need to design a repair for the current loads. However, I would still step through the evaluation process outlined in the IEBC for substantial structural damage. My position may continue to evolve as I let this marinate for a few days.


The commentary for 502.3 Related Work, under Section 502 Repairs, refers to a wall structure which deteriorated due to improper flashing and the resulting moisture intrusion as the "damaged portion of the structure". So there is at least one instance where the commentary identifies deterioration as damage. I have now sacrificed too much of my lunch to splitting hairs as 1503 said. I'm with you Dik, the OP needs to engage the AHJ as they can always have their own interpretation.


RE: Repairs


the OP needs to engage the AHJ as they can always have their own interpretation.

That's the really nice thing about the Ontario Building Code, Part 11. Remediation is codified and less reliant on the whims of a building official. All codes should have a Part 11.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?


RE: Repairs

Thanks for all the feedback so far... and I hope to get more.... but to add to the discussion; I think the 5year stipulation, in the definition of Substantial Structural Damage, is important because it is important to draw a distinction between damaged caused by structural design flaw(s), and simple neglect... Neglect of a building should not trigger a structural evaluation to current code criteria(even if reductions were used).... should it? As long as it is repaired property (in-kind, to new construction standards) there is no reason to doubt the structural integrity, capacity, or behavior of the structure, if the damage was caused purely by neglect. right?

RE: Repairs


Say you open up a load bearing exterior wall to replace rotted framing and discover that the window openings are absent appropriate headers? Would you just restore the wall to its pre-damaged condition because the rot was a result of neglect? but on the same exact wall you would add the headers as part of the reconstruction if the wall was hit by a car?

I don't think the cause of damage is a good distinction to base your repair decisions on.

What compliance method are you pursuing?


RE: Repairs

Hey LuK13,
If I saw something that was obviously undersized by observation, or poorly/dangerously framed, or anything that was an obvious structural concern, I would certainly address it.. even if it wasnt my job.. even if I was just walking by and happened to see something on a construction site...

That's not the topic here. And, that would not void the overall approach, or method, or understanding for addressing a repair due to neglectful maintenance.

Chapter 4, Repairs. CEBC.

RE: Repairs


Sorry for appearing to go off topic, sometimes analogies are not the best tool.

My interpretation is that if you hit the trigger for substantial structural damage, you meet that trigger regardless of the cause of the damage. I believe the spirit of the IEBC is to draw a line in the sand and say that after you have to repair/renew this much of a structural system, you need to evaluate that system.

I think that this matter is being complicated by the fact that damage and deterioration are very different things to people working in certain industries, such as the insurance industry. I don't believe the people that drafted the IEBC had this distinction in mind when they chose the term "substantial structural damage" otherwise they might have opted for a more neutral "substantial structural deficiency".

I've made my opinion known, so I'll sit back and see if anyone else weighs in. I would also be curious to hear how things work out for you once you have made your decision and moved forward with the project.


RE: Repairs


Any update on how your project has gone?


RE: Repairs

Not yet, we were delayed.

And, I do anticipate some interesting discussion with the building department... so I will certainly share. Im going to present an argument based on my interpretation, which was cemented by this discussion(along with just letting it soak in), all thanks to the group, and see where it goes.

I know they'll want more.

I won't forget to update.
I appreciate the interest.

Thanks LuK.

RE: Repairs

To update those interested; We have recieved response from the building department. They say they will allow us to proceed with the necessary upgrade of the existing wall sheathing, without evaluating any other portion of the building.

I have required periodic observation, so I can check the framing as they remove portions of the sheathing.... but am hanging my hat on the fact that this is an upgrade to even the original construction.. let alone current conditions... that it is essentially deferred maintenance.

Thanks for the feedback.

RE: Repairs

Thanks for checking back in. Hope the project goes well.

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