Mechanical room wall coverings

Do the framed walls in a mechanical room, in the basement, need to be covered with drywall or can they can be covered in OSB? The mechanical room contains a propane forced air furnace, two propane hot water heaters, a heat recovery ventilator, a humidifier, all of the fire suppression system and the electric panel. I know that it would obviously make sense that the walls be fire rated, but is it a requirement?

Not around here. Mine doubles as an unfinished storage room as well.

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It wasn’t while I was inspecting and still isn’t, I don’t believe.

If you want to play Code Inspector, maybe you should call Codes and ask?
What applies here may not apply there.


Yes. But changes have to be made as of today, to today’s code.

Back in the day (many days ago) the ceiling above an oil fired furnace required a fire barrier where I lived, but that is long gone.

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Do you keep track of all the codes in all the areas you work and the timeline of changes for the past 100+ years? How else can you possibly inspect a house to the standards it was “built to” at the time?


Where though? You can Google the year the house was built and the particular item you are interested in, but you will be going down an endless, hopeless rabbit hole in no time, lol. And then you also have to figure out if the area the property is located in was using that version of the code at the time of construction.

It’s simply not possible to do all of this for every inspection. At best you are shooting from the hip on whether something was officially allowed at the time or not. And good luck trying to call the local code officials. Most of my report refinement and cleanup is done after normal business hours at city offices. And even if you actually get ahold of someone the next day or two, they likely will not be able to answer your question unless it is brand new construction. So your client is waiting on the report until you hear back? Isn’t going to work in the long run in my opinion.


You inspect houses based off of age instead of by defect?

My clients don’t give a shit what the code was when the house was built. They want to know that their family will be safe in it TODAY!!


I inspected houses in the condition that I found them.

Others could accept and change it or not. :man_shrugging:

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No. A defect is a defect. Old code is not a defect. Things were actually built better 50 years ago. I find more structural defects on a brand new house then one built more then 50 years old. Builders have no pride in their work these days. I would suggest adding GFCI outlets to the kitchen and bathrooms on an older home, but would be a major defects in new construction, due to code.
Things like that. Major, minor, or repair items different by the age of the house is all I’m saying. It’s not black and white.
I can’t call out 2x4 rafters on a 1900 house, but I sure would on new construction.
Come on guys you all do the same.

You’re right, it’s definetely not always black or white. I think we all develop our own set of standards that we apply somewhat on existing construction, especially century homes.

I get asked periodically (usually by agents) what the code was at the time. My answer is “I don’t know, but regardless, the issue is worth being aware of now.”


I’m not embarrassed to say “I don’t know”, following up with something like… “It doesn’t matter though, because (our) clients aren’t moving in 100+ years ago. They want to move in next month, and I’m sure they want it to be as safe as practical. It’s not their fault we didn’t know what was/wasn’t safe back then. They shouldn’t be penalized for old methods. I was hired by them to discover these short comings and advise them in a written report. The safety of their family is my highest priority”!

Not many realtors want to go near the “family safety” statement!


Safety is important to the client…at least it was to mine and important for me to report on it no matter the year the home was built.

Yeah, I have to in certain contexts. Because my building departments won’t, so sometimes I’ll have to pull out an old code book and familiarize them with the nomenclature myself. However: precision is not always required. You can tell crap work from any era. Survivor bias means older crap work probably already caught fire and was removed. So in general, the older the work the more likely it’s not a problem now.

Old 2x4’s for example: what matters is they’re bowed, not that they don’t meet today’s code.