How to Install a Chimney Cap 3

One important thing to remember when it comes to installing a chimney cap on your own is to remember to wear protective gloves! Often times,

single flue chimney cap
This can be placed over a single flue chimney or two can be placed over a chimney with two flues if they are spaced far enough apart.

stainless steel or other metal chimney caps have extremely sharp edges. Similarly, if the chimney cap you have purchased has instructions from the manufacturer, those should be followed instead of any other procedure. If you are going at it alone, you’ll have to first take measurements for it. An important measurement that people always forget about, whether they are measuring to install a single flue or multi flue cap is the height of the tile that sticks out of the chimney. If it is very tall you may need to make special arrangements ot have a height extender installed.

If you have only one flue in your chimney then you will simply measure the dimensions of the flue at the top of the chimney. If you have more than one flue in your chimney you will need to decide whether to have two single flue caps or one multi flue cap. Two single flue caps are appropriate for when the two flues are located far enough apart that two single flue caps will fit side by side without having to be bent. If your flues are located to close together then a multiflue cap, which screws into the crown itself and covers the area over and surrounding the two flues would be more appropriate.

After taking measurements and ordering your cap, you will need to install it properly in order to prevent having to keep reinstalling a cap that has blown off in the wind or having to buy a new cap if it blows off and gets damaged. For a single flue cap all you will need to do is place it over the flue and screw the screws in to tighten it on. I always recommend applying a thin ring of silicone for the cap to sit on. This will prevent it from blowing off in strong winds. If you are installing a multi-flue cap you will need to screw it directly into the crown. I recommend using a thin ring of silicone again to ensure that the cap does not come flying off. Multi-flue caps are usually custom made and can get expensive, especially for very large sizes. You don’t want to have to purchase two of them if one falls off and is bent beyond repair.

Band around caps are a less utilized option for multi-flue caps. Instead of screwing this cap into the crown, they actually “band around the top of the chimney.” Measure the outside dimensions of the top row of all four sides of the first row of brick . Make sure these are exact! This cap will actually fit around these brick snugly and you attach them with screws.

One final note, I do not recommend using black painted galvanized steel or aluminum covers where oil or coal is being burned or wood/pellets are the primary source of heat.

Clay Lamb

Clay Lamb

Clay Lamb is a Cincinnati Chimney Sweep contractor and the executive producer of the YouTube channel, podcast, and blog Ask the Chimney Sweep. He is also an award-winning educator and public speaker in the chimney and fireplace industry.….Educational Videos….Chimney products….American Chimney Cincinnati, OH
Clay Lamb


  1. I just had my cap blow off in a strong wind – looks like it was held on by rivets that popped off. It’s just a metal flue pipe that sicks up above the roof.

    How would I attach a metal cap that fits into the pipe? Is there
    holes I need to drill and attach with sheet metal screws of some kind? Or is it all done with compression fitting?

    Seems like I’d want to screw the metal together, to help with wind, but I haven’t seen many people talk about it on the site’s I’ve visited.

    – Joe

  2. Do a Youtube search! I have screwed many a cap into both concrete, and metal to keep those funny looking little Frisbee style flying caps from going airborne Batman

  3. @admin
    Wow, I can’t believe it’s been a year since this happened.

    I ended up screwing the cap right to the pipe with some self-drilling sheet metal screws, seems to have held up well so far.

    I also learned a 2 story house is waaaay scarier than my previous 1 story house, and I was paying so much attention to not falling I ended up making the cap crooked – nothing most people would ever notice, but it catches my eye every time I look up!

    This winter, the wind blew off big sections of the metal facia along the front and side. I’m hiring that one out…

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