Residential attic ventilation

I have a dumb question.

How did the evolution of attic ventilation responsibility land on the roofers' lap? I had a home builder ask us to provide attic ventilation on a custom home.....WTH?

I can't recall, who had previously made the comments, on how "accepted practices" come about...Possibly they'll chime-in here. Anyhow.....

It amazes me as to how roofers have taken on the responsibility of attic ventilation. I suppose it's a regional thing, as well as re-roof, (prime contractor), vs. new construction, (subcontractor), dynamic.

Attic ventilation, is absolute calcuable, as per IBC/IRC. Anything beyond that, should be referred to an authentic HVAC professional. HVAC contractors have engineers on staff for that purpose.

Roofers should understand the liability they are exposing themselves to. Can you image what a court would do to a roofer in a construction defect/mold situation? Here we have a roofer, who simply unilateraly decided, by the seat of his pants, how to vent a particualr attic...The opposing litigants have HVAC professionals on their team.....Yikes!

Just a thought.....

Wywoody.....That's crazy! However, I can understand....Here, they've run bath/kitchen vents right into the attic spaces! I would hope that doesn't go on anymore, w/new construction....Haven't checked lately.

O/S......Most of our work the last couple of years has been general construction...and yes, as with re-roofs, we sometimes address venting...However, when you take on that responsibility, one needs to have it absolutely covered....So I understand what your talking about, and your definitely doing the right thing.....To reiterate; You are esentially taking on two different trade aspects...Roofing & HVAC.

Oh! and the roofing material manufactures meddling with their venting recommendations.....They could very well end-up with thier teet in a wringer one day & have to give up some pie!

Egg; Agreed....I was trying to maintain an abreviated version (LOL)......In my round-a-bout way, I was simply attempting to point out the possible implications/liability of unnecessarilly assuming responsibility for something that really doesn't have to be, and virtually, is by trade definition, anothers', (HVAC).

Understandably, in this narcisistic/"pie-eating" society we must live & work in, risks are always there...Why not reduce the risks if one can?

For reasons stated, we're very explicit, to exclude ventilation design, in our contract agreements. We'll install it; Just not "design" it.

Out here (in Ca) now, every set of prints has to have ventilation requirements posted. That means intake, exhaust, type and location of vents. A rudimentary numerical calculation to explain the notations. All part of the Title 24 business. Insulation is also specified. That takes a lot of the guesswork off the table. Best to walk yourself through those, though.

Nothing so far has been hammered down on reroof, over-the-counter permits, at least in my zones. But people are jumpy and lawsuits are lucrative for some segments of the working population. Meaning, to put it bluntly if not cynically, plans and specifications or no, if you are working on any project today you may well become a member of the great American pie-eating contest tomorrow. This is a high-stakes, nominally civilized activity where entry fees are not required. All one needs is to have been in vague proximity to a supposed blunder in order to be entitled to a piece. Nobody goes home hungry. It's like playing pin the tail on the donkey where everybody gets a tail and you hope that yours is just one of the small ones.

Making claims to quantifiable expertise you may not have is not a very good idea, but neither is complying with expertise you know (or should have known) will or even merely may fail. You can get the white hat smacked right off your head just for having presumed to wear it, but you can also get smacked for not having put it on. You really really need to know your customers, know your terrain, and develop your instincts. Definitely know when to walk and have the strength to support that knowledge with appropriate action. As a clarinetist once remarked to me when I asked him how he felt after his solo performance, "It's a rush." I still get a thrill out of some of this stuff. And to think excitement can sometimes hinge on something as trifling as whether or not to install a little piece of hardware just there or just there.

If it fails, you aren't allowed to claim you were just there. Down the road a piece, even smart people (especially, smart people) have an amazingly tough time "recalling" just what went down, why, and where. There are times when merely living requires an act of courage. My take is a bit like OS' in that if you know your beast, ride him, and if someone tries to take you down for doing what you know is right, it's an honor to die for your principles. By the same token, if I doubt the veracity of a spec, I will politely question it and if the specifier is cheesy in reply, it's game over, no matter what his credentials.

OK O/S

The "code", (I believe both UBC, as well as IBC & IRC), used to be, (for the past 30 yrs anyhow); 1/300 if equal lower-upper,(eave/ridge) 1/150 if ridge/upper only

"MY" thoughts?.....I dunno...never done a study....It's definitely, ancient technology, that came up with it, as that's been the "rule", ever since I started back in late 70's......Maybe a roofer did...LOL

I suppose one would take the most restrictive/ill-ventilating friendliness type situation, as a "control".

There may be logical/authentic studies out there? Then again; Maybe not....LOL....Job security...LOL

As for the framers cutting holes...That's all they should be doing...Cutting holes. Not deciding what & where...That's up to the HVAC prof....GC has no clue as well....Roofer simply installs as per HVAC design.....Worked just peachy in California. It's a cluster-you know what here in Colorado, where no one really knows or cares.....Hence the const. defect issues.....This is a fairly arid climate, but the mold/rot is unbelievable.....Then we get into stucco & masonry nuckleheads.....Don't get me started

My point is that your taking on the HVAC role/liabilities.

Most of us, that have done this for any time, know and agree with what you stated, simply through experience......However, why does the GC/HVAC/Architect/Engineer/designer, off-load this on the roofer?

I remember back in the late 80's, in California, there were "energy" laws/mandates that came about...Every home had to be specifically energy-calculated, by an HVAC engineer....The idea of a framer or roofer simply guess-by-golly, designing attic ventilation, was preposterous.

I used to do the very same thing, for the very same reasons.

These days I've noticed roofers, as well as shingle manufactures, taking on more attic ventilation responibilities.

With the widespread use of ice & water shields over the past decade or so, we're really experiencing exponentially more ventilation/mold issues.....It's going to get real ugly.