Horizontal Rain and Chimney Leaks

November 19, 2013 · Filed Under Home Maintenance 

So last week we had a lot of rain.  Not unusual for this time of year.  The rain was horizontal.  Not unusual for St. John’s.  The unusual part of this was I had a leak in my attic.  I had new roof shingles installed earlier in the year so I doubted it wBasic Chimneyas that.  I had a peak up in my attic and determined the water was entering from my old chimney.  The chimney was not in use so we just decided to leave it alone years ago.  Out of sight out of mind right?

Doing like anyone would do when “tragedy” strikes, I fired up ye ole internet and proceeded to Google my way to an answer.

Apparently chimney leaks are quite common and quite annoying.  Some sites actually compared them to be as annoying as skylights.

Crown leaks

The chimney crown is the top cement part of the chimney.  If cracked water can find its way into the cracks with potential then to enter your home or attic.  Small cracks WILL lead to bigger cracks so it’s best to address this problem as soon as possible.

Flashing leaks

The flashing is the place where the chimney bricks meet the roof.  Typically an aluminium flashing is installed and then shingles on top.  This is then sealed with black pitch or tar. Tar can dry out over time and crack.  Be sure to watch out for this.  Flashing leaks appeared to be the greatest cause of leaks in a chimney.

Mortar and brick cracks

I didn’t realizChimney mortare this but bricks and mortar both allow water to pass through, i.e. they are not water proof. Water can seep in and freeze in the winter.  If we all remember grade two science classes, water expands when frozen causing cracks in the mortar or brick.  And to make matters worse, if you add a water proofing material on the exterior of the chimney when the bricks are already wet, the water has no place to exit, except for the inside of the chimney and hence will end up inside your house.

Lack of chimney cap (cover)

It’s amazing to drive around St. John’s and notice this now, but there are quite a number of homes that have chimneys yet lack the chimney cap.  Leaks can occur when rain falls directly into the chimney flue. Seems obvious enough.  Guess who now has a chimney cap on his house :)

The Bottom Line

Remember, home maintenance is important.  While replacing a chimney can be VERY expensive it’s best to not leave a deteriorating chimney and forget about it. If you see a small crack or deficiency, call a local chimney expert and get it repaired or replaced as soon as possible.  Trust me, you’ll thank me for it later.


2 Responses to “Horizontal Rain and Chimney Leaks”

  1. Carter B on December 3rd, 2013 5:02 am

    Some great tips here, Stephen! Fortunately we don’t see as much rain in Saskatoon as you do. Although it’s currently snowing and -20, so our “leak season” will begin once all the snow melts, which seems like lightyears away at this point of the year.

  2. Stephen Winters on December 3rd, 2013 7:21 am

    Snow and -20….ouch! Actually I think I would rather that then St. John’s weather. -10 yesterday and +8 today.
    It’s pouring rain out there now this morning, but at least my chimney is not leaking. :)