Furnace on Bricks

[mtaylor8 (Michael Taylor, TREC 21963)]

I posted in the emergency forum but did not get a response so I am posting here. Is a horizontal gas furnace allowed to be mounted on bricks in an attic?

[cbottger (Charley L. Bottger)]

@mtaylor8

I posted in the emergency forum but did not get a response so I am posting here. Is a horizontal gas furnace allowed to be mounted on bricks in an attic?

You not going to find a specific code that address your furnace. I personally would write up what you found based on MFG installation procedures . Brick would add some extra weight to the ceiling joist and would be an easy transmitter of vibration noise to the ceiling joist and into the living area. It’s basically a dumb installation. I am also an old HVAC person

[mboyett (Michael Boyett, TREC #7290 (Ret) Boerne, TX)]

To be sure, you would need to refer to the specific mfg installation instructions as Charley suggests. There you might or might not find something like this Bryant furnace installation manual snippet:

[wogletree (William Ogletree, TREC License #22530)]

Almost every attic-mounted furnace I have seen (I’m in Texas) was suspended from the roof rafters. I will assume that that is the practice because it is preferable to resting them on the ceiling joists, which are typically not designed to act as a floor system. What does the attic floor (ceiling joists for the room below, typically) look like? If they are 2x8’s on 1’ centers, you are almost certainly fine, but the width of the span comes into play as well.

Suspended or resting on the ceiling joists, the main question is whether that structure is designed to bear the weight. I would not take a HVAC installers word on it.

[escanlan (Emmanuel Scanlan, TREC# 7593)]

@wogletree

Almost every attic-mounted furnace I have seen (I’m in Texas) was suspended from the roof rafters. I will assume that that is the practice because it is preferable to resting them on the ceiling joists, which are typically not designed to act as a floor system. What does the attic floor (ceiling joists for the room below, typically) look like? If they are 2x8’s on 1’ centers, you are almost certainly fine, but the width of the span comes into play as well.

Suspended or resting on the ceiling joists, the main question is whether that structure is designed to bear the weight. I would not take a HVAC installers word on it.

First break down the word “assume” and you will understand why you never “assume” anything!

Re the HVAC installers word then whose word would you take on it? Would you take the word of the manufacturer as asked in this thread https://www.nachi.org/forum/f79/furnace-mounted-bricks-122296/ and an example of one manufacturer pointed out by Mike both in that thread and in this one? As for Charley’s word I would have a tendency to believe him as he has been around the block with this more than a few hundred times! Of course, no offense to Charley, I would still look up the manufacturer installation requirements to verify it. Did you obtain the data plate information from the unit so you could do this?

You discuss loading on the ceiling joists, are you a licensed Engineer that can perform this function? Are the framing members exposed to the point (no insulation covering them) that you can see the interconnection between them which would come into play to determine loading ability? If not you should be very careful about discussing that which may be under the purview of a licensed Engineer and that which you can not see!

[Adam_Dunin]

Hey Mike!

[cevans (Chuck Evans, CMI)]

@wogletree

Almost every attic-mounted furnace I have seen (I’m in Texas) was suspended from the roof rafters. I will assume that that is the practice because it is preferable to resting them on the ceiling joists, which are typically not designed to act as a floor system. What does the attic floor (ceiling joists for the room below, typically) look like? If they are 2x8’s on 1’ centers, you are almost certainly fine, but the width of the span comes into play as well.

Suspended or resting on the ceiling joists, the main question is whether that structure is designed to bear the weight. I would not take a HVAC installers word on it.

The weight of the HVAC system is nothing compared to the weight of the two 50 gallon water heaters up there. Your ceiling joists are more than adequate to support the weight of an HVAC system. Hanging the HVAC from the rafters may help reduce transmission of vibration and noise through the ceiling, but not necessary to relieve the attic floor of the weight of the system.

[wogletree (William Ogletree, TREC License #22530)]

@escanlan

First break down the word “assume” and you will understand why you never “assume” anything!

I think it is reasonable to conclude that in most circumstances, hanging installation is best. Otherwise it would not have become the preferred method. I have no problem coming to that conclusion, your protests notwithstanding.

Re the HVAC installers word then whose word would you take on it?

Someone with construction experience who knows what sort of framing is needed to support specific loads.

Would you take the word of the manufacturer as asked in this thread https://www.nachi.org/forum/f79/furnace-mounted-bricks-122296/ and an example of one manufacturer pointed out by Mike both in that thread and in this one?

Not unless they were familiar with the existing framing, and even then, I would check this against the opinion of someone with construction experience who knew their way around load tables.

As for Charley’s word I would have a tendency to believe him as he has been around the block with this more than a few hundred times! Of course, no offense to Charley, I would still look up the manufacturer installation requirements to verify it. Did you obtain the data plate information from the unit so you could do this?

You asking me or Charley? Would hate to assume anything.

You discuss loading on the ceiling joists, are you a licensed Engineer that can perform this function?

Nope, never said I was. Are you saying that I must be a licensed engineer before I can even mention such things?

Are the framing members exposed to the point (no insulation covering them) that you can see the interconnection between them which would come into play to determine loading ability?

It would be important to do so. Did I say anything to the contrary?

If not you should be very careful about discussing that which may be under the purview of a licensed Engineer and that which you can not see! I am very careful about such things.

That’s why I used the qualifiers “almost certainly”, and “other factors play a role”. My post was mostly cautionary in its nature, pointing out the need to find out whether the attic floor was constructed adequately to support the loads being placed on it.

Topics on this forum routinely run into areas that are the “purview” of any number of licensed professionals. Plumbing, electrical, framing, grading, soils, the list goes on. Are you going to come out and wag your finger at us every time such topics come up? If so, you will be a busy man indeed.

[wogletree (William Ogletree, TREC License #22530)]

@cevans

The weight of the HVAC system is nothing compared to the weight of the two 50 gallon water heaters up there. Your ceiling joists are more than adequate to support the weight of an HVAC system. Hanging the HVAC from the rafters may help reduce transmission of vibration and noise through the ceiling, but not necessary to relieve the attic floor of the weight of the system.

I went back through both threads on this topic and at no point found any mention of two 50-gallon water heaters. Did I overlook that? If there are 2 50-gallon water heaters up there, I would be even more hesitant to place an additional load on the attic floor.

In most cases, typical ceiling joists would probably be up to handling the load, but I have seen ceiling joists that were nothing more than the bottom chord of a 2x4 truss system on 2’ centers. Without any information about the ceiling joist dimensions, their span, how closely they are spaced, and the weight of the load being placed on them, I would not venture an opinion. But that’s just me.

[escanlan (Emmanuel Scanlan, TREC# 7593)]

@wogletree

                 Originally Posted by **escanlan**                     [https://nachi.cachefly.net/forum/images/2006/buttons/viewpost.gif](https://www.nachi.org/forum/f20/furnace-bricks-122299/#post1704713)                 
             *

First break down the word “assume” and you will understand why you never “assume” anything!

I think it is reasonable to conclude that in most circumstances, hanging installation is best.

Valid conclusions are based on relevant and useful facts. Here you have chosen to make a conclusion based mostly on your own observations and “opinions” of how something should be done. In the other post regarding this you were provided the actual building code requirements for installation of HVAC equipment which state it will be installed as per the manufacturer’s requirements. Below in this very response you state that you would not trust the manufacturer’s own requirements for installation. Possibly you know a great deal more than the manufacturer?

Otherwise it would not have become the preferred method.

When we inspect and continually find an installation method that is wrong, whether it is wrong by the manufacturer requirements or the building codes, that does not necessarily make that installation method correct but possibly the “preferred method” of installing it wrong.

I have no problem coming to that conclusion, your protests notwithstanding.

You are free to come to any “conclusion” you wish and I have no protests other than spreading possibly false information to other Inspectors who might be reading the post or in this case the consumers who might be reading this post in an open section of the BB.

Re the HVAC installers word then whose word would you take on it?

Someone with construction experience who knows what sort of framing is needed to support specific loads.

So using this example you must appear to question everything that you were taught about home construction and must obtain the advice of someone who is in construction to verify everything you report on when inspecting a home. That leads us with the expectation that either your reports are very small since you would not report on something you could not verify or it would take you forever to write a report since you must consult with a person who has “construction experience” on anything you plan to report.

Of course you could perform a good inspection and write an accurate report if you did inspect and report to manufacturers’ specifications.

Would you take the word of the manufacturer as asked in this thread https://www.nachi.org/forum/f79/furn…bricks-122296/ and an example of one manufacturer pointed out by Mike both in that thread and in this one?

Not unless they were familiar with the existing framing, and even then, I would check this against the opinion of someone with construction experience who knew their way around load tables.

Again your inspections and reports must either take forever to complete or are missing many items that should be reported. Obviously you don’t trust the manufacturer to specify how to install their equipment. You also would not trust an HVAC Installer’s opinion on how the equipment should be installed (as noted above). So just out of curiosity at what point would you stop checking, doublechecking, triple checking, ad infinitum, until you get around to reporting on a defect?

As for Charley’s word I would have a tendency to believe him as he has been around the block with this more than a few hundred times! Of course, no offense to Charley, I would still look up the manufacturer installation requirements to verify it. Did you obtain the data plate information from the unit so you could do this?

You asking me or Charley? Would hate to assume anything.

I am asking you even though you are not the OP on this post. Do you even obtain the manufacturer data plate information on an item that you might have a question on if it is installed properly? Of course I would have to expect with your answer above that you do not trust the manufacturer to specify how their equipment is to be installed and that you possibly don’t bother to obtain the data plate information to even look up how they specify it to be installed?

You discuss loading on the ceiling joists, are you a licensed Engineer that can perform this function?

Nope, never said I was. Are you saying that I must be a licensed engineer before I can even mention such things?

You are attempting to calculate loading on a structure not just speak about it. You are free to do anything you like and none of us here can stop you. Hopefully all you are doing is attempting to obtain an education and not advising clients about loading matters unless you have the proper license to do such. We, other Inspectors, are not the ones you must worry about and instead you should be concerned about landing on the list of TREC’s page here TREC Disciplinary Actions Page.

Are the framing members exposed to the point (no insulation covering them) that you can see the interconnection between them which would come into play to determine loading ability?

It would be important to do so. Did I say anything to the contrary?

That was a lead in question as I did expect this type of answer. This is your lesson for today it is something you can Google search and learn. It is called the “Load Path” which encompasses much more than just the horizontally installed framing members. There are members in the “Load Path” that unless the drywall is off, or you have the original house plans, you’re not going to be able to see to verify.

If not you should be very careful about discussing that which may be under the purview of a licensed Engineer and that which you can not see! I am very careful about such things.

That’s why I used the qualifiers “almost certainly”, and “other factors play a role”. My post was mostly cautionary in its nature, pointing out the need to find out whether the attic floor was constructed adequately to support the loads being placed on it.

Nice try at bailing out! I’ll refer back to the paragraph I wrote above with the term “Load Path”

Topics on this forum routinely run into areas that are the “purview” of any number of licensed professionals. Plumbing, electrical, framing, grading, soils, the list goes on. Are you going to come out and wag your finger at us every time such topics come up? If so, you will be a busy man indeed.

Wagging fingers is under the purvey of those attempting to defend actions they should not take. As a result I do not spend any time wagging fingers.

I would expect by now you would learn that attempts at twisting around another persons words are not the answer to any situation as displayed in this post https://www.nachi.org/forum/f2/suggestions-truly-useful-pool-spa-inspection-course-122166/index2.html.

To help keep the conversation straight I have answered your blue wording above with red wording as replies to it.

[cevans (Chuck Evans, CMI)]

@wogletree

I went back through both threads on this topic and at no point found any mention of two 50-gallon water heaters. Did I overlook that? If there are 2 50-gallon water heaters up there, I would be even more hesitant to place an additional load on the attic floor.

In most cases, typical ceiling joists would probably be up to handling the load, but I have seen ceiling joists that were nothing more than the bottom chord of a 2x4 truss system on 2’ centers. Without any information about the ceiling joist dimensions, their span, how closely they are spaced, and the weight of the load being placed on them, I would not venture an opinion. But that’s just me.

So who mentioned trusses? What is the point of your rampant assumptions about an installation that you know nothing about. Are your inspections full of all this same B.S. and made up nonsense “almost every”, “I will assume”, “typically”. You’re way the hell out on a limb that you don’t belong on.

“I would not venture an opinion. But that’s just me.” The issue is that you have ventured an opinion. An ill-informed one at that.

[jdeoliveira2 (John Paul de Oliveira, GB-2 #86934 / AB #44580)]

Charleys answer:
“would be an easy transmitter of vibration noise to the ceiling joist and into the living area. It’s basically a dumb installation.”

[wogletree (William Ogletree, TREC License #22530)]

@Manny and Chuck

I will go back to what I said before:

“the main question is whether that structure is designed to bear the weight.”

I honestly don’t see what the problem with that statement might be.

“I would not take a HVAC installers word on it.”

Because there is NO WAY the HVAC installer knows the details of the construction at the point of installation. Now, if the installation instructions were available and went into specific detail about structural requirements to support that specific unit, then I would be more inclined to take their word as long as those conditions were met at the point of installation. Keep in mind that in this example the weight of the bricks come into play as well, which again, the manufacturer cannot possibly know.

[escanlan (Emmanuel Scanlan, TREC# 7593)]

@wogletree

@Manny and Chuck

I will go back to what I said before:

“the main question is whether that structure is designed to bear the weight.”

I will go back to what I said before.

• “This is your lesson for today it is something you can Google search and learn. It is called the “Load Path” which encompasses much more than just the horizontally installed framing members. There are members in the “Load Path” that unless the drywall is off, or you have the original house plans, you’re not going to be able to see to verify.”*

Unless you can visually see the method of construction from the point of placement to the footers you can not possibly have any idea whether there is insufficient support to mount that unit either on blocks or hanging by straps!

I honestly don’t see what the problem with that statement might be.

You are fixated on calculating loading in a building. Do you also calculate the load of a tub full of water and verify the structure (joists below it) has been properly built to handle the load? Do you calculate the weight placed on kitchen cabinets and verify the structure has been properly built to handle the load? Do you calculate the load of a roof structure and verify the structure has been properly built to handle the load? Do you calculate the possible loading of a second floor floor and verify the structure has been properly built to handle the load?

I can go on and on with the examples but the answer is absolutely you do not do that and can not do that since the structure, along with the “Load Path” beneath that HVAC unit, is not visible with drywall and other coverings over the “Load Path”! We can not see these things but you are here on a publicly viewed forum leading consumers to believe that we somehow can. That is a significant disservice to the public to make that impression.

Instead what you should be doing when inspecting is to view the surround and visible structure for signs of stress that might be connected to the method of installation and reporting that to the consumer.

“I would not take a HVAC installers word on it.”

Because there is NO WAY the HVAC installer knows the details of the construction at the point of installation.

And neither do you know “the details of the construction at the point of installation”. I will go back to what I said before about the “Load Path”. Anything that you can see the HVAC installer can see. I seriously doubt every HVAC installer is a genius with building methods but they don’t need to be and seem to do just fine installing equipment with the structural knowledge they have. Very, very few HVAC companies are hacks and those generally do not last long in business anyhow!

Now, if the installation instructions were available and went into specific detail about structural requirements to support that specific unit, then I would be more inclined to take their word as long as those conditions were met at the point of installation.

Now you’re being absolutely silly! What you propose is that every manufacturer write a specific installation manual for every house built that their unit would be installed in. To meet your requirements the manufacturer would also have to have detailed plans for the home so they can see the method of construction. So even a 50 year old home would need to have its original design and as constructed plans made available to the manufacturer.

Keep in mind that in this example the weight of the bricks come into play as well, which again, the manufacturer cannot possibly know.

And you know the weight of the “bricks” how? Do you also remove bricks and weigh them so you can use it along with the weight of the unit in your "load calculations? Do you weigh the unit as well so you can calculate loading?

Answers to your question in blue and red above.

I think you really should stop as the hole just keeps getting bigger for you. If you wish to speak about this it is better for you to use the thread started in the MO section of the BB.

Chuck provided a very good point in an earlier response about the pair of 50 Gallon water heaters mounted in an attic. I’ve run into my share of this very installation. His example no doubt was to display how a properly installed joist system, and platform, has the capability of handling an approximately 1000 Lb load in what is typically no more than a 4’ X 4’ area. Do you believe that an HVAC system typically spread out across an approximate 5’ - 6’ line would not be handled properly including with any “bricks”?

As I said before there is certainly nothing wrong with any Inspector trying to learn and think of how a piece of equipment might be loading the framing. However don’t leave consumers with a wrong impression that Inspectors should all be calculating and verifying loading when they can not since we can not see all conditions needed to do that. Also there is no reason to even try if the installation is not displaying signs of stress on the structure!

[cevans (Chuck Evans, CMI)]

@wogletree

@Manny and Chuck

I will go back to what I said before:

“the main question is whether that structure is designed to bear the weight.”

I honestly don’t see what the problem with that statement might be.

“I would not take a HVAC installers word on it.”

Because there is NO WAY the HVAC installer knows the details of the construction at the point of installation. Now, if the installation instructions were available and went into specific detail about structural requirements to support that specific unit, then I would be more inclined to take their word as long as those conditions were met at the point of installation. Keep in mind that in this example the weight of the bricks come into play as well, which again, the manufacturer cannot possibly know.

Well, bless your heart. You just go right ahead and write up every attic floor installed HVAC system that you encounter as a possible structural defect in need of a full engineering evaluation in your reports to your clients. Best wishes to you in your new career. Please don’t advise other inspector to do so though. There’s no need for them to ruin their reputations too.

[jdeoliveira2 (John Paul de Oliveira, GB-2 #86934 / AB #44580)]

Mr. Ogletree,
Like Mr. Scanlan said it is good you formed the question; the answers have been provided by the dynamic duo from Texas. They are both quite knowledgeable. If you were to pick up and move a furnace, you might find it is not that heavy, lighter than a lot of furniture. Many roof trusses are designed with snow loads in mind, as they are based on national standards. The areas without snow are sometimes subject to hurricanes. Either way, they are shored up. I forget the terms, dead load plus live load 10 lb.s plus 40 lb.s per square foot? I should look it up, or ask my father who is an engineer.

I would not take the word of the HVAC installer regarding structural load(s), but it is a relatively common practice. Like mentioned previously the HVAC tradesmen are likely the most informed of the individual trades.

Chuck, thanks for mentioning the 2? WH up there. Never seen even one here. I could never move a filled 50 gallon tank, 400 lbs. Kind of hard to believe, but if you have seen it, you have seen it.

[cevans (Chuck Evans, CMI)]

@jdeoliveira2

Chuck, thanks for mentioning the 2? WH up there. Never seen even one here. I could never move a filled 50 gallon tank, 400 lbs. Kind of hard to believe, but if you have seen it, you have seen it.

And for those times when two, just won’t do…

https://www.nachi.org/forum/attachment.php?attachmentid=195380&stc=1&d=1497129573

[wogletree (William Ogletree, TREC License #22530)]

The original question was, is it OK to install an furnace on bricks. No details were given as to what everything was resting on. Should I have assumed it was standard 2x8 joist floor? Of course not. So, I continue to maintain that the main question is whether that structure is designed to bear the weight.

If I saw a furnace installed on an attic floor supported by 2x8 ceiling joists on 16" centers, I would not need an installation manual, load tables, an engineer’s opinion, or anything else to be comfortable with it. I have enough real world experience as a home builder and re-modeler, and have dealt with load distribution and re-distribution enough to know this. I am not uninformed on the issue.

If, on the other hand, it was installed on a platform set on the bottom chords of a 2x4 truss on 2’ centers, and I know many homes in my area with exactly that configuration, I would have to take a good hard look at it before I could comfortably say that it was a safe installation.

My point is this: It is the inspector’s observations in the field - not the generic instructions in manufacturer’s literature which have no insight into the facts on the ground (or in the attic as the case may be) - that informs the inspector’s opinion.

I have a tremendous amount of respect for Manny, as he obviously has loads of experience and technical knowledge. Likewise with Mr. Evans.

That being said, I will always use my training, past experience, guidance from code, and common sense when I evaluate whether any installation is proper or safe. Taking someone else’s word for it - especially when they are not privy to the specifics of the location - seems to me the easy (and risky) way out, and not what I was hired to do.

[escanlan (Emmanuel Scanlan, TREC# 7593)]

@cevans

And for those times when two, just won’t do…

https://www.nachi.org/forum/attachment.php?attachmentid=195380&stc=1&d=1497129573

Awesome!! I’ve done some doubles, quite a few singles but I don’t ever remember a triple! Thanks for the pic as well. I was trying to find a double but it has been a while and that means looking through a lot of picture files.

BTW that’s over 1200 Lbs of water alone and must have topped close to 1500 Lbs. total. Did you calculate the loading to ensure the installation was properly performed?

[escanlan (Emmanuel Scanlan, TREC# 7593)]

@wogletree

The original question was, is it OK to install an furnace on bricks. No details were given as to what everything was resting on. Should I have assumed it was standard 2x8 joist floor? Of course not.

I think we already went over that an Inspector should never “assume” anything!

So, I continue to maintain that the main question is whether that structure is designed to bear the weight.

If I saw a furnace installed on an attic floor supported by 2x8 ceiling joists on 16’ centers, I would not need an installation manual, load tables, an engineer’s opinion, or anything else to be comfortable with it.

I think we need to end this discussion of “Engineered Design” factors. Let’s say that the unit is resting on “bricks” which are all resting on the access platform. Since you can not see underneath this platform then what do you do? Do you advise the client that there “might” be a loading problem or do you say nothing?

BTW I’ve never seen joists placed 16’ on center. Is that a new thing?

I have enough real world experience as a home builder and re-modeler, and have dealt with load distribution and re-distribution enough to know this. I am not uninformed on the issue.

Yes I see that on your WEB site how you have been building homes since you were 9 years old. You say you have oodles and oodles of experience. So do you inspect a home from the perspective of a builder with oodles and oodles of experience, verify all possible loading points and that they are sufficient to handle the loads, and make a definitive call describing why in detail that there is a loading issue? Do you perform this same protocol on every home you inspect?

If, on the other hand, it was installed on a platform set on the bottom chords of a 2x4 truss on 2’ centers, and I know many homes in my area with exactly that configuration, I would have to take a good hard look at it before I could comfortably say that it was a safe installation.

I have to go with what Chuck said before which is “So who mentioned trusses?”. I’ll add to it to ask why are you trying to divert from the OP’s question or any discussions we’ve had so far in this thread?

A “full” truss roof design that you are speaking of is typically designed only for the weight and loading of the roof structure to begin with. The truss types used here in a typical roof design do not even provide for proper access and clearances required by building codes to even install an HVAC unit in the attic. So you’re not providing any new and startling revelations here.

BTW I have seen HVAC units installed in attics using a truss roof design and that is the way it was engineered. Of course this was done by stopping the truss roof structure and switching to conventional framing to create the required access for an HVAC unit which was mounted on the floor. This whole roof was engineered and displayed no signs of stress. Am I then not suppose to trust an Engineer’s design and verify loading?

My point is this: It is the inspector’s observations in the field - not the generic instructions in manufacturer’s literature which have no insight into the facts on the ground (or in the attic as the case may be) - that informs the inspector’s opinion.

And we have been saying what multiple times over? Maybe you finally get the point that if there are no visible signs of stress in a conventionally framed attic then we expect through our “observations” there are no loading issues occurring! Of course if there are signs of stress and/or damage it should be called out. At that point any Inspector that wants to make a claim it is a loading issue caused by the HVAC unit they are more than welcome to. Most likely over time we will be reading about that Inspector here TREC Disciplinary Page.

I have a tremendous amount of respect for Manny, as he obviously has loads of experience and technical knowledge. Likewise with Mr. Evans.

Thank you but I do not know everything about construction and am not afraid to let my clients know that! The worst thing any Inspector can do is lead a consumer down a primrose path trying to have the consumer believe they know it all! Someone made a good albeit a little hard statement that I recently read.

“There is very little more infuriating (and even dangerous) than someone who thinks they know it all. [Name] recognizes that learning is a lifetime endeavor, and recognizes that every new experience holds the potential for new knowledge.”

That being said, I will always use my training, past experience, guidance from code, and common sense when I evaluate whether any installation is proper or safe.

You should always use your training, past experiences,codes when applicable, and common sense when inspecting. To do anything else would be a detriment to the client and make an Inspector nothing more than a “Checkbox Chimp” who knows little, doesn’t bother to learn anymore than is required by law, and inspects to the minimums. However making any claim that you are inspecting to an engineering level is very dangerous for both the client and the Inspector.

As for the “codes” statement these references from the 2012 IRC were provided in the internal thread. Mike also provided at least one manufacturer who states installing an HVAC unit on non combustible blocks or bricks is allowed. These code references state you will install a unit as per the manufacturer’s requirements. So if you are going to follow the “codes” when inspecting the answer to the OP’s question is it depends on what the manufacturer allows.

M1307.1 General.
Installation of appliances shall conform
to the conditions of their listing and label and the manufacturer’s
installation instructions. The manufacturer’s operating
and installation instructions shall remain attached to the
appliance.

**M1307.2 Anchorage of appliances. **
Appliances designed to
be fixed in position shall be fastened or anchored in an
approved manner. In Seismic Design Categories D1 and D2,
water heaters shall be anchored or strapped to resist horizontal
displacement caused by earthquake motion. Strapping
shall be at points within the upper one-third and lower onethird
of the appliance’s vertical dimensions. At the lower
point, the strapping shall maintain a minimum distance of 4
inches (102 mm) above the controls.

**M1401.1 Installation. **
Heating and cooling equipment and
appliances shall be installed in accordance with the manufacturer’s
installation instructions and the requirements of this
code.

Taking someone else’s word for it - especially when they are not privy to the specifics of the location - seems to me the easy (and risky) way out, and not what I was hired to do.

As an Inspector we are hired to inspect, find the deficiencies and/or signs of a deficiency, and properly report what we find. As I stated before if you feel the need to perform an Engineer’s job of calculating and verifying loads just because something does not look right to you (no visible signs of an issue) you are certainly free to do so. Here in this discussion, in an open forum completely visible to the public, that appears to be exactly what you are claiming to do. You are also claiming you will take no other persons word for how “something” should be and will verify all installations (not just the HVAC unit), verify all operational aspects of a system, and will essentially verify the house has NO hidden issues even if that piece, system, or structural element has no visible or basic operational signs of problems. During this entire discussion it has been explained why that is a disservice to consumers.

There is absolutely nothing wrong with exceeding the bare minimum SOP that we are required to follow. I do it every chance I get! However I also use “common sense” to know what my legal limitations are during an inspection and what is actually worth exceeding or not. I certainly don’t want that call from a client who was led to believe I rise to the level of inspecting that you propose and who later finds out a hidden issue was not reported on!

Answers in blue above.

As I stated you are best served starting a new thread in the MO section or continuing the existing thread in the MO section of the BB!