Robin Jade Conde

PODCAST: Gas Appliances and Masonry Chimneys

In this podcast, Reuben and Tessa discuss the problems with chimneys and the venting of exhaust gases from appliances. It highlights the issues with older masonry chimneys and the need for proper venting with more efficient appliances. They also discuss the importance of chimney liners for gas appliances in older homes. They highlight the potential dangers of not properly venting gas appliances and the risk of condensation and chimney deterioration. They emphasize the need for HVAC contractors to go beyond simply connecting appliances to the chimney and to ensure proper venting. The conversation concludes with a reminder for homeowners to consider the potential unintended consequences of upgrading their heating systems in older homes.

Takeaways

Older masonry chimneys are not suitable for venting more efficient appliances
Clay tile liners protect the chimney from corrosion
Condensation and back drafting can occur when the chimney is not properly heated
Modifying the chimney is necessary to accommodate the lower heat output of newer appliances HVAC contractors often need to pay more attention to properly vent gas appliances, leading to potential problems with condensation and chimney deterioration.
Installing a chimney liner is necessary for gas appliances in older homes to reduce condensation and ensure proper venting.
The cost of installing a chimney liner can vary depending on the height and accessibility of the chimney.
In some cases, it may be more cost-effective to install a power vent water heater instead of lining the chimney.
Homeowners should know the potential unintended consequences of upgrading their heating systems in older homes.

Chapters

00:00 Introduction and Background
04:59 The Dangers of Improper Venting
08:40 The Importance of Awareness and Education
09:58 Efficiency of older and newer appliances
10:33 Preventing Chimney Venting Issues
11:54 Chimney temperature and exposure to elements
14:40 Dangers of condensation and back-drafting
15:44 The need for chimney liners
20:29 Installing metal liners
24:55 Power vent as an alternative to liners
27:12 Unintended consequences of energy efficiency upgrades
29:19 Importance of hiring a chimney contractor


TRANSCRIPTION

 

The following is a transcription from an audio recording. Although the transcription is largely accurate, in some cases it may be slightly incomplete or contain minor inaccuracies due to inaudible passages or transcription errors.

 

Reuben Saltzman: Welcome to my house. Welcome to the Structure Talk podcast, a production of Structure Tech Home Inspections. My name is Reuben Saltzman. I’m your host alongside building science geek, Tessa Murray. We help home inspectors up their game through education, and we help homeowners to be better stewards of their houses. We’ve been keeping it real on this podcast since 2019, and we are also the number one home inspection podcast in the world, according to my mom. Welcome to the Structure Talk podcast. Tessa, where are you today? You are not in Minnesota, are you?

 

Tessa Murray: Hey Reuben, I am not. I am in sunny Tampa today, I’m in Florida.

 

RS: Oh my goodness. Okay. Love it. Love it.

 

TM: And I’ll tell you what, I’ve been here long enough to think that coming out of a pool and being in like 88 degrees feels a little cool. [laughter]

 

RS: You’re getting super spoiled.

 

TM: Yeah. No, but it’s… I will tell you, there are some pros to all of this sunny warm weather. There are beautiful flowers. There’s banana trees and pineapple bushes in the backyard. So that’s nice. However, the bugs are intense.

 

RS: Yeah.

 

TM: I mean, all the different species of ants, the fire ants, the carpenter ants, the sugar ants, like I don’t dare walk in the grass barefoot. Termites, drove past the house that was tented the other day.

 

RS: Oh really.

 

TM: And I think it’s getting treated for, yeah, bombed for termites.

 

RS: Okay.

 

TM: So it’s a war on mother nature down here.

 

RS: Yeah. Have you gotten bit by any ants yet?

 

TM: Not on this trip. I did the last time and I got bit on my toe by a fire ant and my whole foot swelled up. I had this red line of like inflammation going up my vein, up my foot, up my leg. My whole foot was like red and swollen. Took like a day for it to go down. And then, yeah, that bite was like itchy for like weeks. It was nasty.

 

RS: Yikes. Yeah. Those things are bad news.

 

TM: They’re not good. I don’t know. Do you have reactions to stuff like that?

 

RS: Oh yeah. I got bit by a couple of fire ants once when I was in Florida. And…

 

TM: Yeah not fun.

 

RS: It felt like a bee sting or something. I can’t believe how bad that hurt.

 

TM: They’re really painful. And I’m lucky I just had one on my toe. ‘Cause usually like before you realize it, if you’re standing in a fire ant colony, like they’ll just get on you and then they’ll all start biting you. And you get more than one bite very quickly.

 

RS: Yeah. I’ve heard that.

 

TM: Yeah.

 

RS: Yeah. Glad it was just one.

 

TM: I… You know Minnesota doesn’t have fire ants and it doesn’t really have termites at this point. So that’s a plus, but yeah I swam in the ocean yesterday and went to the beach and enjoying all of those things. So can’t complain.

 

RS: Sweet, sweet, sounds fun.

 

TM: Can’t complain. How about you? How’s life for you?

 

RS: Life is good. Life is good. I can’t complain. Had a good time up at the cabin. Did some pretty intense dirt biking and ATV riding.

 

TM: How did you almost kill yourself this week?

 

RS: I was very safe. I had no problems. I shouldn’t say I was very safe, but I didn’t almost kill myself. I had no close calls, had another rider who was up with us lose control of the big ATV. We got out to 700 and they they took a tree out a little bit, but they were just a little shooken up. They’re wearing a helmet, all was fine. No big problems. So it was good.

 

TM: Had a beer and then went back out. [laughter]

 

RS: That’s about it. Yeah. We try not to do any drinking before riding those things ’cause…

 

TM: That’s smart.

 

RS: You need all of your faculties.

 

TM: For sure. I didn’t know that you dirt biked. Of course you do.

 

RS: Yeah. Yeah.

 

TM: Mountain biking. Is that the same thing? Like do you do mountain biking too or just?

 

RS: Yeah. I got into that ’cause my son joined a mountain bike team. So we do this thing called a single track riding where it’s all one direction.

 

TM: Okay.

 

RS: And it feels a little bit like dirt. I mean a dirt bike, it’s a motorcycle, but…

 

TM: Yeah.

 

RS: Yeah. Single track mountain biking, tons of fun. If anybody’s out there who likes thrill seeking, they haven’t done that. That is a lot like dirt biking.

 

TM: Yeah.

 

RS: And that you need to pay attention and you turn away for a split second you’re gonna hit a tree or something. Like it takes a lot of focus.

 

TM: Yeah. Wow.

 

RS: It’s fun. But all right.

 

TM: Yeah. Let’s get to the…

 

RS: To the show.

 

TM: Let’s get to the guts. Yeah. So what are we, what’s the topic for today, Reuben?

 

RS: All right. So today’s topic is this is based on a blog post that I had written earlier in the year, like in February. And we’ve been meaning to get Scott on the show to talk about this. Scott’s one of our inspectors and he’s also a chimney inspector. He’s the lead chimney inspector for our team. We’ve got a bunch of people do chimney inspections, but he said, “Reuben, you need to cover this. You need to tell people about all the problems with chimneys.” And I wanted to get him on, but it just has not worked. And I don’t wanna let this go for too long. So we’re covering this topic today. And the issue is how do I say this succinctly? Basically back in the day, we would have masonry chimneys taking the exhaust gasses for our appliances like furnace, water heater, whatever it is.

 

RS: They’d take those things up and out of the house and it would all work really fine. But as we get more and more efficient with our appliances, we start running into problems and we’ve got installers replacing furnaces and water heaters and boilers all over the twin cities. And as I’ve learned from teaching at different parts of the country, it’s not exclusive to Minnesota. This is happening all over the country where you’ve got installers replacing these appliances, but they don’t even look at what’s going on with the venting. And we got chimneys falling apart left and right and appliances improperly vented all over the place. So I thought this should be a good wake up call for anybody who’s a home inspector or concerned with houses, real estate agent.

 

RS: Everybody ought to know about this and the magnitude of it, so I gave some of it away, but we need to explain this in detail, so.

 

TM: Let’s delve into it. Yeah.

 

RS: Let, let’s do it. All right, Tess. First off, masonry chimney. What are the components that we got for masonry chimney? What are the layers that I’m asking about?

 

TM: Well, I was gonna say, you hit the nail on the head. Not all houses have masonry chimneys, but a lot of times, at least in the housing stock that we see, it’s in older homes. Yeah. So like 1900s, ’20s, ’30s, ’40s. And they would build chimneys out of brick, some sort of masonry, and, they would go from the basement all the way up through the roof. Sometimes they’re on the side of the house. And then inside of that masonry structure, a lot of times you’ve got some sort of clay tile liner that goes all the way up as well. Not every chimney, but most.

 

RS: Yeah. And what’s the purpose of that clay tile liner?

 

TM: Purpose of that liner is just to reduce the size of that, chimney opening, I think, and to provide some sort of cavity for that combustion gas to vent up and out of the chimney.

 

RS: Yeah, exactly. And it’ll be glazed. And the idea is that those combustion gases aren’t going to tear it apart. When you’ve got those combustion gases, which, which the byproducts of those combustion gases when they condense, it’s, basically like if you’ve got steam, I mean, you see it coming out the top of your chimney, it looks like steam coming out. There’s a ton of water vapor in there, and when it ends up condensing what’s left over is going to eat the heck out of mortar. I mean, it’s a very corrosive product. It’ll destroy mortar very quickly. But when you’ve got that clay tile liner going up through the middle of the chimney, you’re protecting all of your mortar joints. The only mortar that it ends up seeing is the mortar joints in those huge clay sections.

 

TM: Yeah.

 

RS: And they are very thin mortar joints, so. There’s barely any exposed mortar once you’ve got that proper liner. Right.

 

TM: Yeah. That’s a good description.

 

RS: Okay. All right. So that’s basically two layers that you’ve described. You’ve got the structure, which is the brick, then you’ve got the liner.

 

TM: Yeah.

 

RS: Which is the clay tile. And then we’ll get to the next layer that we might see. We’ll get to that in a minute here.

 

TM: Sure.

 

RS: But let’s see where, where did I wanna go with this? So we’re talking about these appliances, they’re venting into the chimney and you’ve got what seems like steam.

 

TM: Yeah.

 

RS: And it’s, so what makes all of that exhaust leave the chimney? How does this work?

 

TM: Warm air is less dense than cold air. Right. So cold air will sink and the warm air will rise. And so when these furnaces or boilers or water heaters kick on, you’ve got all these flames and combustion, it heats up that exhaust gas and the byproduct just floats up the chimney and that’s through gravity, basically.

 

RS: Okay.

 

TM: Naturally buoyant.

 

RS: Yes. And so we go back in time and we’ve got an old gravity furnace venting into that chimney, and it might be like 100,000 BTUs.

 

TM: Sure.

 

RS: That’s a unit of measurement for how much energy it uses. Let’s say that thing is 50% efficient. What does that mean, Tess?

 

TM: Oof. That’s crazy. But yeah, but true. So these older heating appliances, 50% efficient means that 50% of the potential heat actually goes up the chimney. It doesn’t go to heat the house So, and we’ve got more and more, energy efficient appliances today. So you fast forward now we’ve got, 95, 96, 97, 98% efficient furnaces where, only 5 to 2% of the potential heat gets wasted out through the exhaust gas. But back in the day, the appliances were not efficient.

 

RS: Yeah.

 

TM: So a lot of heat, which you’re getting at, I think is a lot of that potential heat would go up the chimney instead of being used to heat the house, which not good for the homeowner or for your pocketbook, but great for the chimney. The chimney loves it.

 

RS: Great for the chimney. It’s a healthy happy chimney. Yes.

 

TM: Yeah.

 

RS: The more heat you waste by not heating your house, that’s the more heat that goes to the chimney and you end up with very little condensation. ’cause everything just stays super hot. And all the exhaust gases rise up and out and it works really well. And now, and there was one other thing I wanted to touch on. The temperature of the chimney is gonna depend on where it’s installed. You said that sometimes you got chimneys in the middle of the house, sometimes you got them on an outside wall, and then sometimes you have one wall of the chimney sharing an outside wall. Sometimes you have the chimney sticking out of the house. So you’ve got three walls of the chimney exposed to the elements.

 

TM: Exposed, yeah. Which I haven’t thought about too much before, but, those chimneys that have a lot more exposure to the elements or to the cold temps in our northern climate will struggle even more to potentially keep a warm interior. So good point.

 

RS: Yeah. And, so those chimneys, it’s especially nice when you have a ton of wasted heat making the chimney healthy and happy. It reduces the condensation it almost eliminates the condensation going on and everything rises up and out. But now you fast forward, step forward in time a little bit, and you’ve got, say, an 80% efficient furnace. And that’s one where it still vents up through gravity. Whether you have a metal vent going through the middle of the house, or you’ve vented into your masonry chimney. Either way, those exhaust gases are going up through gravity. But now let’s say you’ve got a 100,000 BTU furnace again. But you’re gonna step it down to… You’re gonna make it 80% efficient. Now instead of wasting 50,000 BTUs, you’re gonna…

 

TM: You’re only wasting 20.

 

RS: 20. But, but wait a minute now, Tess. That doesn’t work because now what used to heat the house with 50,000 BTUs, now we’re giving 80,000 to the house. That’s not gonna work. We’re gonna have to downsize the furnace. We’re gonna have to bring it down to like a 80,000 BTU furnace.

 

TM: Good point.

 

RS: So now we’ve got 80% of 80,000 BTUs. Yeah. That’s still 64,000 BTUs. That’s still more than the house needs, but just for the sake of argument.

 

TM: ‘Cause it used to have 50, now it’s got 64, even with a smaller furnace, smaller BTU appliance. Yeah.

 

RS: So now with that, what’s left over for the chimney now we’ve got 16,000 BTUs heating that chimney. Where we used to have 50.

 

TM: Interesting.

 

RS: And I’m just being theoretical. In reality, it’s gonna be even less than 16,000 ’cause you would have dropped the furnace down even more. I’m making, I’m making a well, who cares? The point is you’re having way less heat being wasted in that chimney, and now you’re gonna have a really cold chimney. So what happens when you vent your little un-wasteful furnace into that huge chimney, Tess?

 

TM: Gotcha. Well, it has a much harder time establishing a draft for sure. It’s a lot of surface area diameter for that much smaller BTU appliance to heat. And usually it can’t especially if it’s extreme temperatures out and you’ve got a chimney on the exterior of the house. So you’re asking for potential problems with condensation of the exhaust gas on the inside of that chimney, which can lead to corrosion and deterioration of that chimney and even worst case scenario, potential backdrafting of combustion appliances.

 

RS: And what is backdrafting for anybody just tuning in, they haven’t listened to all of our podcasts in the past.

 

TM: What is backdrafting? It’s when the exhaust gases come back into the house instead of venting out the way they should either through the masonry chimney or through another vent, but they actually sink back down and potentially even get pulled into the house depending on the pressures. So this is a potentially really dangerous situation. We might joke about this, but I mean, this could be, if you’ve got a appliance creating high carbon monoxide in the exhaust gas, if it’s not burning properly, working properly and it’s just dumping that combustion gas back into your home, that could be a life-threatening situation.

 

RS: Yes.

 

TM: So we do not want that.

 

RS: Yeah. And so what does it take if we’re still gonna vent this newer appliance into that masonry chimney? How do we fix it? How do we get the exhaust gas to get up and out and not condense on the inside of the chimney and destroy it?

 

TM: Wait, you mean you’re supposed to do something to the chimney when you put in a more high efficient appliance?

 

RS: Oh, I know it’s crazy, right?

 

TM: What? There’s another step that needs to be done besides just swapping out your furnace or swapping out your boiler?

 

RS: And this is what’s not being done. This is what’s unfortunate is that you can hire a heating contractor to come out and replace your water heater, replace your furnace, whatever. They’ll pull a permit, they’ll get it all inspected. And after they connect it to the chimney, they’re done. Nobody looks inside the chimney. Nobody looks up it, down it. Nobody cares what’s going on. They just figure once we connect there, we’re done. That’s where the HVAC contractor’s job typically ends. Now I’m not saying all of them can’t speak for everybody. There are some out there that are very diligent and they care what’s going on on the other side of that chimney wall. And they make sure the exhaust gases are gonna get up and out, but most of them don’t. And I know this ’cause Scott, part-time, well in the winter, he’s working for another chimney contractor and he’s going into house after house after house where they’re having problems. And all of these are new installations where the heating contractor never did anything with it.

 

TM: Wow. Now here’s a question I’m curious about and you may not know the answer, but I wonder how many of these HVAC contractors also do like a draft test when they change out the furnace or boiler and maybe the homeowner still has a like a natural draft water heater that’s venting up that chimney. How many HVAC contractors check to make sure that water heater, that orphaned water heater, in the worst case scenario, now it’s venting alone. Let’s say you put in a high efficiency furnace that vents out the side of the house. It used to vent up the chimney with the water heater and it would help heat up the chimney, help the water heater draft. Take that away. How many HVAC contractors are checking that water heater when they replace the furnace?

 

RS: I would hope every single one.

 

TM: You know I would too, but I would guess that it’s probably 0%. I don’t know. What do you think, realistically?

 

RS: I really don’t know, I really don’t know, I would hope every one of them would. And we do this during home inspections where we do a worst case scenario, you turn on the kitchen fan, bath fans, clothes dryer, you make sure all the windows are shut, furnace is off, then you fire up the water heater.

 

TM: Yeah, and check.

 

RS: It needs to survive in the worst case scenario. And technically we call it worst case scenario, it’s not truly worst case. Worst case is gonna be its negative 20 outside where that air is especially heavy, it’s especially tough for it to establish draft, and maybe you’ve even got a bad wind pushing the exhaust gases down. And that’s truly worst case, we’re not doing real worst case. Worst case that we can realistically set up during a home inspection.

 

TM: Yeah, yeah, yeah. In terms of like homeowner operation of a house, let’s create the most negative pressures we can, but we can’t control the weather and stack and outdoor temperatures and wind, so yes.

 

RS: So they should be checking this when the new appliance is installed, but the big fix here that we’re getting to is that you in almost every case, you can’t simply connect the appliance into the chimney with a clay tile liner. ‘Cause it’s gonna be a huge space, it’s fine for a wood burning fireplace, but you’ve got a little gas appliance with a small BTU in there. What needs to happen is they need to install a metal liner and it could consist of a corrugated metal liner, it’s a slinky looking stuff. It comes in a big roll and they run it all the way down the chimney and they connect to it at the base. Or they could use a rigid metal liner and it might consist of four foot sections of galvanized metal, it might be… Depending on how many BTUs, what type of appliance you got, it might be a four inch, five inch or six inch, it’s pretty rare to have a seven. It’s almost always a four or a five or a six venting into that chimney and they’re gonna put together these sections, it’ll be four foot sections of sheet metal basically to make up a flue. Run it down the chimney a little bit, connect the next section on with some sheet metal screws, keep running it down. And basically now you’ve got this big liner that goes all the way up through the middle of the chimney.

 

RS: So you have a very small space that needs to get heated up now and you dramatically reduce the potential for condensation inside there. That’s a chimney liner.

 

TM: Thanks for explaining the chimney liner. Now, I’m wondering, okay, so if you would need a chimney liner in a few different scenarios, one could be maybe you upgrade your really old eating appliance, which we don’t see many of those 50% efficient appliances anymore. So if you’ve got let’s say you’re upgrading to an 80% efficient furnace, that would use a metal flue, right?

 

RS: That’s right. Yep.

 

TM: And it would still need to vent up and out through the house somehow. Newer houses, it’ll just be a metal flue sometimes going up and out through the roof, it’ll be a double wall B-vent, but in an older house, that metal flue would go up the masonry chimney still.

 

RS: That’s right.

 

TM: You’d need a liner for that, okay.

 

RS: That’s right. And you hit an important point, Tess. If it’s a newer home, like the last house I used to live in, it was built in ’98. And I had a furnace that vented right up through the middle of the house and it had a B-vent, that’s an important term you brought up. And this is a fancier vent, it’s a double wall metal vent and it can pass through finished spaces inside the house. And you can have your clearance to anything combustible reduced down to whatever the manufacturer of that B-vent tells you. Everybody says, oh yeah, B-vent clearance is one inch, there’s nothing in the code that tells you the clearance of B-vent. The code tells you the clearance is whatever the B-vent manufacturer allows, and almost all the manufacturers, there are very few exceptions, they say one inch. So typically you can reduce the clearance to combust almost down to one inch, you can run that through the middle of the house, it’s a fancy material. But when I’m talking about installing a liner and a chimney for a gas appliance, I’m talking about some really cheap material. This stuff is like…

 

TM: Okay.

 

RS: Maybe a buck or two a foot and it’s single wall, it’s not a fancy B-vent like you’re talking about.

 

TM: Okay.

 

RS: It’s not a UL listed product. So putting distinction there.

 

TM: So I wonder… Yeah, thanks for explaining that. Do you have any idea how much it costs to have a liner installed in a typical chimney? And I know it depends on the height of the chimney and all of that and accessibility, but…

 

RS: Oh, man.

 

TM: Any idea?

 

RS: This is where we should have Scott on the show right now ’cause he could tell us right off the top of his head.

 

TM: Sure.

 

RS: The one thing I do remember, ’cause I remember he told me not long ago, I’m embarrassed at how not long ago it was and I already forgot.

 

[laughter]

 

TM: Wait, your brain doesn’t remember every single detail going in it all the time? What?

 

RS: I should, the one… My one takeaway was it was way more than I would have guessed.

 

TM: Okay, see that’s what I’m getting at. So that leads me to my next question is, I think more people these days are probably going to be installing the most efficient furnace that they can get probably, right? So 90% plus condensing high efficiency seal combustion furnace, which uses PVC pipe to exhaust the combustion gases out through the side of the house, typically. So it’s not going up through the chimney anymore, it’s going typically out through the rim joist on the side of the house.

 

RS: That’s right.

 

TM: So that leaves you with an old water heater that we see this in a lot of houses in our area, where they’ve got the high efficiency furnace and then they’ve got the natural draft, natural gas water heater that still has a metal flue that needs to vent up and out somehow. And now it’s venting up through that masonry chimney all by itself. Do you think it’s worth the cost of, let’s say they’ve never lined that chimney before, you’ve got a problem to now line it, even though you’re putting in a furnace that doesn’t need it anymore, you still have a water heater that needs it. So you line it for just the water heater or you forget about having to line that chimney and you wait a couple more years for your water heater to go out and then you put in a power vent water heater. That you don’t have to worry about lining the chimney, the cost of the liner, and you could potentially even take down the chimney if it’s in bad condition. And you also, pro of that, is you don’t have to worry about ever backdrafting or having combustion gases coming back into the house.

 

RS: Yeah, Tess, if it came down to look, either you need to put a liner in or you need to do a power vent, I would surely wanna do a power vent.

 

TM: Power vent.

 

RS: Instead of having to put in a liner. Yeah.

 

TM: Agreed. So really the only scenario that makes sense is if you’ve got a house where you have to have like a boiler or a furnace that needs that chimney for combustion gases and will for a while, that’s when you wanna spend the money on making sure you’re lining it.

 

RS: Yeah, or somebody already did the upgrade to the furnace and they’re running out the side of the house and then they finished their basement, and maybe it would be cost prohibitive to run the venting for that furnace through the side of the house. But you know what, you could even run the PVC venting for the water heater up through the chimney too, you could do it for the furnace too. I’ve seen it done before, it’s not common.

 

TM: Yeah, that’s true. Yeah.

 

RS: But I’ve seen it done and that is a nice chase way if you can get someone to fish that piping up through there.

 

TM: If it’s a big enough chimney, yeah, and you can fit the pipes up.

 

RS: Yeah, and the chimney is basically just reduced to a chase way, that’s all it is at that point.

 

TM: Yeah, okay.

 

RS: So it’s another option. But yeah, I’m with you Tess.

 

TM: This whole conversation, it circles back, doing this house coaching, consulting, a lot of people in older homes and they’re trying to make their homes more energy efficient. They’re trying to not only maintain them but upgrade them in different ways, and you take an old house that had an old system and it used to work just fine. [laughter] And all of a sudden you start making changes and you think you’re making good decisions by upgrading to a high efficiency furnace and all these things. But you create these potential unintended consequences unknowingly. You potentially cause…

 

RS: Unintended consequences, yeah.

 

TM: Yeah, you potentially cause condensation in the chimney that starts eating away the inside, deteriorating the chimney or it causes your water heater to start back drafting. So it’s just really important, I think, if anyone’s listening to this, just to understand again, the house is a system and you take an old house and you “update it” just be aware of all the potential issues you could create by doing that.

 

RS: Yes, yes. All right.

 

TM: What’s the… Can you clarify for me one thing, Reuben?

 

RS: Yeah.

 

TM: What is… How long does it take for a chimney to actually be really so disintegrated that you’ve got a real problem? How long does a exhaust appliance need to be venting into a chimney for it to eat away the inside? What does that look like?

 

RS: I honestly don’t know, I don’t know how long it takes, I don’t. My best guess would be probably about five to 10 years before you start seeing signs of it. It’s not gonna be overnight.

 

TM: Okay, it’s not overnight. And the main concern with that is it just, it literally eats away the inside of the chimney, it starts collapsing on itself.

 

RS: Yeah. The mortar starts falling apart, and then…

 

TM: Okay.

 

RS: You end up having bricks just falling down on each other, you have gaps in the outside of the chimney, you’ve got mortar washing away where you can just wipe it away with your finger. Yeah.

 

TM: Got it.

 

RS: It really eats away that mortar, that’s the big issue.

 

TM: Now, can’t you just slap some stucco on the outside of that brick?

 

[laughter]

 

TM: To hold it all together.

 

RS: And then have the chimney just fall apart on the inside. Yeah.

 

TM: Oh, wait, you’ve got pictures of that.

 

RS: Oh, so many pictures. Oh my goodness.

 

TM: Yeah, yeah, so that’s not a good solution.

 

RS: Yeah, yeah, that’s bad news.

 

TM: Okay. Yeah, when it gets to that point, you need to rebuild it or remove it.

 

RS: Yeah, yeah. So the bottom line here is that if you’re having a contractor come, a heating contractor come out to replace a furnace or a water heater, a boiler, something that’s venting into your masonry chimney, you should not have the expectation that they’re gonna be doing anything after the chimney. Typically, that’s where their work stops, there’s a lot of…

 

TM: You mean where the vent connector connects to the chimney, usually?

 

RS: Exactly.

 

TM: In the basement?

 

RS: Exactly.

 

TM: Okay, that’s the end point for them.

 

RS: That’s the end point for what they do, for what they look at. Don’t assume they’re gonna do anything past that, if they do, that’s wonderful, but it’s a good question to ask. You need to figure out what’s happening on the other side of that, are you gonna look at it? And if they’re not going to, you need to hire a separate professional to come out, and it would be a chimney contractor. You would need to hire a separate chimney contractor to come out and inspect all of that work because most HVAC contractors don’t deal with any of that. They punt to chimney contractors to have them take care of putting in the liner, dealing with all that stuff. And it’s very important, so don’t assume that your HVAC contractor is going to take care of it, that’s the big message here.

 

TM: Thank you for that important lesson.

 

RS: Bless.

 

TM: For all you homeowners out there that have older homes with masonry chimneys look into it. Hey, what’s a good tip for someone, if they want to know if they’ve got a metal liner, is there a way to look at the chimney from the exterior without climbing on the roof and looking down it, to see if there’s a metal liner?

 

RS: Yeah, I’m gonna put a link to my blog post in the show notes, you could click on that link and I’ve got a bunch of examples showing what those metal liners look like. But yeah, you should be able to see the metal liner from the ground. If you can’t see a metal liner from the ground, it’s two possibilities, number one, you don’t have one, number two, it stops short of the top of the chimney, which is also a problem. It should always come up through the chimney, you should see it sticking out. If it ends short, it means that wherever it stops, you’re gonna start deteriorating the chimney right there. So yeah, absolutely, you should see metal sticking out of the middle of that chimney if you have a metal liner. And like…

 

TM: Good tip.

 

RS: Tess, I do just gotta say, everything we’re talking about today applies to gas appliances venting into these masonry chimneys, if you have a wood fire venting into that, that’s a totally situation, it’s not what we’re talking about today.

 

TM: Thank you for clarifying that. Yeah, and tune in someday when we do have Scott on the podcast to talk about probably level two chimney inspections then. You can hear about all the horrors with masonry fireplaces in that situation.

 

RS: Yeah, yeah, we’ll get him on someday.

 

TM: Yeah, sounds good. Okay.

 

RS: Cool.

 

TM: Well, I think we covered a lot of ground, a lot of territory, and yeah, we went pretty deep on chimneys. This podcast is a little bit longer than we thought. [laughter]

 

RS: Yeah, that’s okay, there’s a lot to talk about. And Tess, I just checked to see the Facebook live to see if it was working. And I saw something else on my Facebook page and it reminded me, this is the other thing I wanted to bring up. We’re gonna have to bring it up at the beginning of next show, but for anybody who tuned in this long, had to share, you were featured on a show just recently, Tess.

 

TM: [laughter] Oh, yeah, yeah.

 

RS: We should have talked about that, we’ll talk about it in the next episode, but…

 

TM: Sounds good, we’ll save it for next time.

 

RS: Yeah, yeah, we do need to talk about that whole experience.

 

TM: That was fun, that was really fun. You were a part of it too, yeah.

 

RS: Just a little, I showed up.

 

[laughter]

 

TM: And Neil. Neil made a little appearance too.

 

RS: Oh my gosh, it was great, yeah. Well, we’re teasing next episode, we’ll talk about that at the beginning of the show. That’ll be fun.

 

TM: Sounds good.

 

RS: I don’t wanna rush through it today.

 

TM: No, no, we’ll save it.

 

[music]

 

RS: Okay. All right, well, for anybody who tuned in live, thank you for tuning in live, we’ll try to get our act dialed in next week where people can actually ask questions and maybe we’ll have a little announcement saying when we’re gonna do it, so people can join on it in the comments.

 

TM: Oh, what a brilliant idea.

 

RS: I don’t know, we’ll see, we’ll try it.

 

TM: We’ll try, yeah, we’ll try, perfect.

 

RS: All right. Thanks again for tuning in, I’m Reuben Saltzman with Tessa Murray, We’ll catch you next time. Take care.

 

TM: See you.