waterproofing responsibility

[struct_eeyore]

Hi all.

How do you deal with with waterproofing responsibility on small project w/o an architect? In my area most single family residential plans are signed w/o a second thought to waterproofing; but I am naturally curious as one cannot exclude a contractor screwing something up on a more complicated job. Do you make a note to say "structural aspects only"? Do you press the homeowner/builder to get an architect involved? Do any of you get involved with waterproofing? A couple of SE's I've worked with previously, with ~100 years between them, would not touch waterproofing at any cost, so I have developed a healthy amount of anxiety about it...

 

[CANPRO]

I take the same approach as your previous colleagues - avoid it. Unless you're knowledgeable enough about the design of waterproofing systems to consider yourself a professional in the field, then you shouldn't offer professional design services in this category.

On smaller projects, pushing the responsibility to others(or even identifying the issue) can fall on deaf ears - I usually just cover myself with a note stating "building envelope by others".

 

[skeletron]

I've signed off on the waterproofing/flashing on a building schedule once before. But never again. It was on something minor but it's a whole different level of expertise that I'd rather not stick my neck out for.

 

[NorthCivil]

on small projects, they dont have an HVAC engineer, an electrical engineer, etc. so the responsibility to figure these items out falls between the architect/designer and the contractor.

Structural engineer isn't responsible for an electrical fire should one break out, so why would a structural engineer be responsible for a leak?

A note on the drawings wont change anything IMO. more important is not to start answering questions when they are directed your way that arent directly relevant to the structure, as i find builders often do when the structural engineer is the only professional on the project.

 

[JAE]

We never do waterproofing.
We never do residential.

Check out Eng-Tips Forum's Policies here:
faq731-376

 

[WARose]

For residential, I would think you would refer to the architectural drawings. However for industrial, I've almost always included (for example) water stop details.

 

[Ron]

I routinely do waterproofing. While it is not usually something structural engineers want to deal with, I think it is important to protect the structure and not leave that to a bunch of half-ass details that allow water intrusion.....but then, I deal a lot with remediation,not new design and the remediation comes from failure investigations of the building envelope and the structure.

Similarly, many do not consider windows to be structural components. They are clearly part of the components and cladding and offer protection (enclosed, partially enclosed) to the structure.

If you don't have experience in waterproofing, don't touch it. If you do, do it right and protect the structure. The IBC and most of the state derivative codes require that if water passes the exterior envelope plane, it must have a means to get out such that the structure is not damaged. This is critical for cold formed steel and wood framing systems.....less so for cast-in-place concrete and masonry structures.

Just as the envelope can affect the structure, the structure can affect the envelope. Pay particular attention to wall deflections.

 

[TheDW]

We work on a lot of residential...if its a detail where we know waterproofing will be needed, we will just add some text to the detail saying 'waterproofing by others' or something similar, just to (hopefully) draw attention to it. We won't go any deeper than that.

We pretty routinely get asked to approve waterproofing for inspections, and we've never done it to my knowledge.

 

[MotorCity]

We let the architects handle it, they are more experienced experts when it comes to the building envelope. We always coordinate the waterproofing details with them just to make sure they are not doing something wacky but we simply place a note on our drawings "Refer to architectural drawings for waterproofing details". Generally speaking, the building will still function from a structural standpoint with or without waterproofing.

 

[Ron247]

I would not get involved designing waterproofing but would definitely put notes stating the Owner, Contractor etc. is to design and install waterproofing. I would put the notes in both the General Notes and on specific details when waterproofing is necessary. About 15 years ago, we have several different apartment complexes start losing exterior porches because lack of waterproofing allowed water to rot out the wood around bolts that attached the steel and concrete porch to the 2nd floor framing. Once one bolt pulled through, the rest of them dominoed. There was a time when the City allowed this type of attachment. After installing a bunch of them, 20 years later, they started falling.

 

[8thStreet]

As a structural engineer who does a lot of residential and small commercial, we always show waterproofing and flashing at critical locations (at basement walls, at cantilevered deck joists, deck ledgers). Our note reads like - "full height sheet metal flashing between deck ledger and house, ref architect for waterpoofing details"

I know it is easy to be liability averse - But it is more important to protect structural components so they do not fail due to water infiltration

I have seen many jobs where contractors do not install the waterproofing because it isn't on the arch or the engineer plans, and that is a recipe for disaster, so now I always call out non-specific waterproofing and say REF Arch.