I’ve been talking about the code in my last few blogs. It’s big and growing and it includes references to a library of other documents with equal clout as “code”. The code is really larger than that though, as manufacturer’s installation instructions for nearly everything that makes up a home, from shingles to windows to clothes dryers are referenced by the code, and thus, part of the code as applicable. I’ve had many an eye raised at me when I ask the owner at an inspection if they have the installation instructions for their furnace. Men get grief all the time about not reading instructions or asking for directions, but trust me, don’t try to wing this one. Different manufacturers of similar products often require different installations and limitations. With codes and technology constantly changing, you’ve got to keep current. The furnace instructions I asked for at that inspection were for a high-efficiency furnace (category IV fuel-gas burning appliance, in code talk), and they aren’t discussed much in the IRC, other than a reference to the manufacturer. Nearly everything related to the vents, clearances, condensate, combustion air and appliance location are found in the instructions. A search of the 2009 IRC yielded over 50 direct references. I got tired of counting part way through. I heard arguments before that manufacturer “recommendations” are not “required” by the IRC, but that’s now clear in the IRC, as “recommendations” and “instructions” are referenced.
Even when the IRC doesn’t specifically reference the manufacturer, the requirement is still embedded in nearly everything that makes up a home, through the approval of alternatives. The IRC provides a prescriptive means to build a home using common building materials and equipment; everything else is an alternative. Nothing wrong with that but they are still regulated for proper and safe installation. Alternatives are “approved” when it can be shown through testing or engineering that they are equivalent to what is prescribed in the IRC or will satisfy what is required by the IRC. This is where manufacturer’s instructions come into play. They represent the limitations and installation methods that yielded the performance represented by the test results or engineering. You can’t expect your grandma’s cake to taste like it should unless you make it the same way you “tested”, uh…“tasted” it before – same concept. I’ve often had folks expect me as the inspector to allow variations from tested products, but that’s a leap into a place the manufacturer didn’t even go. While there have been times I’ve worked with something not “perfectly” installed, If the manufacturer could have made the installation easier for you or with fewer published requirements, I think they would have.
Even in referenced standards, the “secret codes” in my previous blog, you can’t get away from manufacturers requirements. While some referenced standards have direct requirements, there are many referenced standards that are merely test standards. They define an established criteria developed for consistent testing of equipment, materials and the like. When a product has a “listing” it has been tested to one of these recognized standard. Listings are required by the IRC in many cases and even for simple items that don’t have typical “instructions”. With a listing, come conditions of that listing, yup…instructions. You may not believe it, but even the little staples used to tack wires to wood studs have requirements and limitations contained within their “listing”. Careful which and how many wires you cram behind those staples, it might not be to code.
If you think you’ve met an overzealous inspector before, just imagine if he asked for all the installation instructions the code technically requires. See, he wasn’t so bad after all! My suggesting is to keep a hold of all the paper that comes with everything you buy for a project. Stick it in a folder and have it ready just in case you’re asked. In the end, turn it over to the owner. Considering manufacturers are the ones that make our products and take liability for them, it seems obvious we should listen to them. This coming from the guy that still tries to turn a box of parts into a bike just from how things look.




