Masonry chimneys without mortar caps and hats can let lots of water into the flue and structure of the chimney. Over time, chimneys can be destroyed by this water infiltration. One of the most obvious signs of moisture infiltration is efflorescence. Efflorescence is the whitish powder that forms on the face of the chimney or in the fire-box of the fireplace. As moisture in the brick evaporates from the surface of the brick it leaves these salt deposits we call efflorescence.
Efflorescence itself doesn't represent more than a cosmetic issue but it does tell us how much moisture is being introduced to the chimney. Right now I am only talking about "outside" sources of moisture. There can also be interior sources of moisture that create or add to the efflorescence. Inside sources are gas and oil heating appliances----especially gas furnaces. These internal sources can actually add more water to a chimney structure than outside sources if the chimney isn't properly lined.
This chimney has no mortar cap and one can easily imagine how much rain it could collect and channel into the chimney structure. Of course the open flues obviously collect a lot of water.
The efflorescence on this chimney almost looks like failed paint---especially on the left side. This chimney is near my house, so I get to watch it annually. The owners frequently clean off the efflorescence and sometimes it looks much worse than it does in this picture. While it would appear to have a mortar cap, there is obviously a great deal of moisture finding its way into the structure----and of course there is no hat on the flue itself. So while a mortar cap is essential to protect the chimney, the cap itself must be functional. They often crack and have gaps around the flue. Keeping these mortar caps well sealed is essential.
If you don't keep the moisture out you will sometimes----under very severe conditions----find efflorescence on the inside of the home as well.
The flue itself should have a proper hat and spark arrestor/vermin screen. This "hat" can keep a lot of water out of the chimney structure.
Sometimes homeowners get very creative about keeping moisture out of the chimney structure and for providing a hat to keep moisture out of the flues. This next picture shows some of the ingenuity I get a kick out of.
My favorite "hat" of all time has to be this functional hat on the chimney for an oil fired furnace.
Charles Buell
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My WORDLESS WEDNESDAY pictures and some selected POEMS & STORIES.
I love what you showed. The caps are so important. I had a bird get into my home several years ago because we hadn't gotten the chimney cap installed yet. Trust me, we got that on quick!
That is quite a collection you have there. You make a valid point that most homeowners just don't think about.
Wow ... Those are some awesome HATS. I don't think they are stylish enough for the Kentucky Derby though.
Sean Allen
Lovely blog. I didn't know that I didn't know much about that efflorescence stuff even though I've seen it on houses and mailboxes and chimneys.
Dana, lots of birds die in chimneys----the spark arrestor/vermin screens are a good way to prevent this.
J. Brandon, thanks for stopping by
Sean, could be the latest fashion trend don't you think?
Barbara, it is always a good thing to come to grips with knowing you don't know:)
Charlie B,
You get an A for effort, just from all the pictures alone.
Charles, Congrats on another star. Some of those are the worst signs of efflorescence that I have seen. Are you sure that our 'ol buddy Bubba hasn't been giving classes on 'home repair' up there?
OMG. Umm.. Charley, aren't those homemade hats dangerous? We have done some building and found out the hard way that chimenys are a frequent source of leaks. Why don't more masons put them on? Not one has ever suggested it to us. We ended up putting them on after the fact.
Well, they say a picture is worth a thousand words--you've done a great job showing us these issues.
CHARLEY - The house that I live in already had the caps when I moved in, so I have no idea what they cost to put in, but it seems that it would be inexpensive enough to have done. Aside from the danger of what they've rigged, it is very unsightly for the neighbors.
Another great post Charles! I'll be headed up your way the end of next week. Has it been raining or has summer arrived in Seattle?
The pictures tell such a great story! thanks for the post. I will mark it and refer to it..especially if I have a client in my area that fights having a chimney inspection. Angelica
Charles, I can tell by the angle of your photos that you do your job well. I mean that you actually climb onto a roof to inspect. I've met quite a few inspectors that think they can inspect a roof & chimney from the ground! Thanks for the info.
I enjoyed this blog and it has a important message. It can be costly to correct problems with chimneys. The pictures are hilarious. I am amazed!
Thanks Charlie for the important information. The "hats" are great. How often should a chimney be "swept" if it has a cap and screen on it?
Wow - Those are some seriously ugly "hats". I am happy that it's not my next-door neighbor's house, although with their dying yard and unsightly weeds, I guess I have enough to deal with (they are tenants).
WOW - I have seen this on homes and did not know/realize this was the problem.
You sure found some ugly hats. Thanks for the lesson.
Steve----looks like this one started growing legs:)
Michael----thanks----we do see a lot of efflorescence here. It would be interesting to know if it is actually "different" in other parts of the country----given the same amount of water movement through the masonry.
Margaret, obviously this last one could blow off and hurt someone----the other was merely a means of capping an abandoned chimney.
Diane, thanks for visiting----I love pictures:)
Adam, one person's "eyesore" is another person's "art":)
Kathy, TOTALLY Summer here right now!
Angelica, thanks for commenting. The one garbage can lid cap wasn't visible from the ground.
Jim, so true----and like I told Angelica---without getting on the roof that one lid wasn't visible from the ground
Joan, you are so right. I did an earlier blog about a chimney that was totally covered with ivy (Why is Oscar the Grouch on my roof?) that was totally destroyed under the ivy but it wasn't visible for inspection.
Christine, the easy answer is: "as often as necessary" but it is complicated by how much it is used and what kinds of fuels are being used. They should certainly be checked annually and cleaned as often as necessary.
Jason,----but the last one had some value----look at all the interest here:)
Karen, thanks for stopping by and commenting.
funny pics but gets me to thinking
Way to go Chuckie B, another feature blog!
Charles, Great post, with some fantastic photos, of the importance of maintaining ones chimney. Mike
I love the garbage can lid cap. That shows someone is very ingenious, very cheap, or maybe both.
Charles: Congratulations on that little gold star! Great information and those photos are beautiful--not really but, they're very informative! As much as I love wood-burning fireplaces, here's a great benefit of having a ventless chimney, huh?!
Kay, thanks for stopping by
Steve, you are a feature
Mike, chimneys are often neglected on homes
Jim, but at least functional:)
Debe, thanks, and I think that it would be long before actual chimneys are very rare.
Great post! We just had a "class" on this at my office -- incrediblly interesting. Water is not your house's friend! And, not to mention the beasties that can come in -- birds, bats, raccoons, squirrels. . . oh my! (a la The Wizard of Oz)
Hi Charles,
While I accompany my inspectors on all of my buyer sides, I don't go up on the roof with them. Can you post or send me a picture of a mortar cap?
Charles...I have not see the "white" on my chimney, but I know I need a cap on it badly. Thanks for this reminder. It's going on the top of the "to-do list." Maybe even before I have the hot dub repaired!
Dawn, thanks for commenting----hopfully I didn't contradict "everything" you learned in class:)
Rick, here is a picture of a mortar cap. While this is not the best design---it is typical and about as good as they get made around here. They technically should overhang the edge of the brick and have a drip grouve on the underside of the overhang. Rarely see them done that way around here. You can see that this one is badly cracked and there are gaps around the flues---all great places for water to get into the chimney structure.
Thom and Ray, glad to be of help
Charles,
Very good information for us chimney challenged. The importance of the mortar cap seems clear. Those creative chimney hats really gives many a pause, I bet.
A "Tip of the Hat" to you Charles. Congrats on the star.
Charlie,
When you told me that you had a photo collection of every house you had ever owned, I had no clue you would turn them into a gold star.
Esko, they have certainly made for some good blog fodder:)
Thanks Kevin
Steve, nice attempt at deflecting from what you know is a fine collection of pictures of a "few" of your rental properties.
Great post - very informative and well put-together. I just want to know - what were you doing, up on my roof, taking pictures of my chimney? :)
Andrew, are you copying Steve?
Charles, those are some great photo's! I love the trash can cover, sure hope the owner's were still USING the fireplace!
Debbie----"functional" (and I use that term very loosly) oil furnace:)
Thanks for posting Charles, I have seen those, didn't know they were seperate from the chimney.
Rick, thanks for commenting. Which part did you not think was part of the chimney?
That is really being frugal. The home owner is a true genius. Glad I don't have them for a neighbor.
Great pictures, great explanatons. Easy to understand!
Carl & Ceil---if they lived next door you would have never ending blog fodder:)
Maya, thanks---glad you stopped by
Sure glad they don't live next to me. I'll let you do the blogging. I have seen some duzzies in my inspection business, much like the rest of you. Still amazes me; instead of fixing something correctly they put a bandage on the problem.
I thought all chimney had mortar caps and that it came with the stack, but obviously that's not true!
Rick, they have to be built when the chimney is built---and maintained perhaps more than the rest of the chimney.
Wow ,People do some funny things. Thanks for the information
Tyrone, you've got that right:) sure makes my job interesting!
That's some fine toppery there! Is that how they do it in the "other" Washington? You didn't bend that gutter putting your ladder against it, did you?
Water is the killer of chimneys, inside and out. Worst case - spalling or chipping of any sort inside the flue that falls down and fills the exhaust port for the furnace or water heater! Yikes! What's worse than back draft? NO draft...
Charles, I haven't been lucky enough to inspect a chimney w/ a trash can lid yet!!
I am over the shocked at what I find stage of my job.... I now find it to be very amusing and some what comical as to the things people do to their homes...
Jay, we have some of the finest "hats" here:)
Nikki, the funny stuff we find sure keeps the job interesting:)
Really good stuff Charles!
I see this stuff a lot as you do. Call someone who knows how to fix a chimney even if it costs you money. It will be cheaper in the long run.
Bruce, thanks for stopping by.