Jump to content

How Much Efflorescence is Too Much?


Recommended Posts

I see this often on chimneys in our region.

Click to Enlarge
tn_2009111722109_DSC04621.jpg

55.79 KB

From the outside, the brick and mortar is reasonbly OK and it's flashed OK through the roof.

Click to Enlarge
tn_20091117221331_DSC04485.jpg

75.37 KB

The roof is new though, and I suspect the old roof had bad, leaky flashing. Also, I'm thinking the flue was uncapped - now it has a weather cap. The mortar crown is cracked and been sealed with a some sort of goop - mortar crowns are typically cracked also.

Point being, I suspect the water typically comes through the flue itself (when it was uncovered), the mortar crown, and seeping through the mortar.

Is this a problem or is just wear and tear?

Link to comment
Share on other sites

Efflorescence is associated with cementitious materials such as brick and mortar. Water moving from behind and out of cementitious materials results in the deposit of salts on the outer face of the wall as the water evaporates.

As far as I know, it isn't an issue, other than to evidence intruding moisture.

Marc

Link to comment
Share on other sites

It needs a new crown.

That much efflorescence means that the stack is taking on a lot of water. The goop that they've sealed that side crack with and the perimeter of the crown isn't going to stop water permeating that stack and it's eventually going to weaken the bond at those top courses of brick. I'd recommend they get a reputable mason to knock that wash cap off there and install a decent reinforced crown complete with expansion joint and built-in drip edge that will ensure water never drains into that stack again.

When you said steel pre-fabricated, were you referring to the heavy steel inserts with the masonry stack built around them and the intake vents below and to the side with the three large heat tubes through the throat above the box or are you referring to a zero-clearance type like someone was asking about last week?

ONE TEAM - ONE FIGHT!!!

Mike

Link to comment
Share on other sites

It needs a new crown.

When you said steel pre-fabricated, were you referring to the heavy steel inserts with the masonry stack built around them and the intake vents below and to the side with the three large heat tubes through the throat above the box or are you referring to a zero-clearance type like someone was asking about last week?

ONE TEAM - ONE FIGHT!!!

Mike

It's an old Fireplace Xtrordinair. I believe it's the style you were describing first.

I'm familiar with the heat tube system but can't think of the name of it right now.

Click to Enlarge
tn_20091118213712_DSC04550.jpg

63.62 KB

Click to Enlarge
tn_20091118213811_DSC04549.jpg

64.29 KB

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...