Ask Your Question

Angie's List Answers is the trusted spot to ask home improvement and health questions and get answers from service companies, health providers and consumers. For ratings and reviews on companies in your area, search Angie's List.

Top 30 Days Experts
Rank Leader Points*
1 kstreett 240
2 Guest_9020487 110
3 Guest_9190926 105
4 GoldenKid 100
5 ahowell 95
6 KnowledgeBase 95
7 skbloom 80
8 Guest_98024861 70
9 Guest_9311297 70
10 Guest_9400529 70

*Updates every 4 hours

Browse Projects By Category

Question DetailsAsked on 3/31/2017

My metal chimney bangs when it rains.

Usually above 50 degrees

Do you have the same question? Follow this Question

2 Answers


Common in the wind, not so much in rain - and a Chimney Sweep (Chimney Repair would be your proper Search the List category, even though most of them will be chimney sweeps who also do repairs) might be able to mount a few stiffeners in that case to reduce the banging, assuming you have a sheet metal chimney shell. Also - if from wind - could be your fireplace damper is open, causing drafting through the firebox and chimney. Close and latch the damper (the cam-lock, roughly foot square door/hatch in the top of the firebox - may have a direct-grab handle which cams shut as you push in/up on it as the door closes, or may have remote operator handle at the side of the firebox to close it.

If only does this once or so during a rain, could be the sheet metal chase cover (also incorrectly called the chimney corwnn by some) on the chimney, or the top of a large flat rain cap, is causing this. This part here - the rusty flat metal area

which is commonly not supported in the center and can flex and dimple downward under heavy rain load (or under any rain accumulation if originally flat or center-concaved, which it should not be) or under snow load. Should be crowned up like following picture to prevent accumulation of rain or meltwater -

I support the center from side to side (just offcenter of the flue) with slotted angle (aka Flex Angle) galvanized angle iron underneath, from side to side of the chase, to keep it crowned up under snow load - should stay up by itself under rain only but no guarantees, and can dimple down under snow or ice load and stay that way and then leak. You might be hearing this or the cap on the rain cap dimpling down (flexing metal can noise) under accumulated load, then popping back up eventually as the water drains/eaporates away. Again, chimney sweep who also does minor rapairs should be able to diagnose and handle it. [If chimney has not been cleaned recently and is used, might be a good timne to get it cleaned to avoide a separate callout charge].

Here is a contractor webpage showing proper creased/raised center chimney chase covers (he calls them chase tops) and discusses why it is important to put support under the center.

One other possibility - sheet metal in chimney is cooling rapidly in the rain and causing the metal to "tin can" - change shape due to thermal changes, though if that were the case not only would it only do it only once or twice in a rain, but would likely do it frequently on sunny days to as the sunlight moves on and off of it. Checking the caps, then removing them (if not the source) and pushing against the sidewall panels should determine where this sound is coming from, and come up with a way to brace it (with as few exterior fasteners as possible, ,and them being well gasketed (with gasketed screws) or at a minimum well caulked under the fastener heads to prevent water infiltration. And no fasterners should go through the flatish top. Course, if a brick chimney finding the guilty sheet metal source will be a LOT easier.

Answered 3 years ago by LCD



This is James in Member Care. Thanks for your interest in Angie's List!

We'll be happy to help find top rated chimney services, but it doesn't look like you have a subscription to the List yet. You can join by visiting or by giving us a call. Our call center is available 8:00 am-9:00 pm weekdays and 8:00-5:00 pm ET on Saturdays.

Thanks for your question and we look forward to assisting you!

Answered 3 years ago by Member Services

Related Questions

Terms Of Use
Privacy Policy