Repair mortar cracks in block wall
#1
09-12-11, 02:44 PM
Join Date: May 2010
Location: USA
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Repair mortar cracks in block wall
I have a Townhome built in the late 70's with a 'look out' lower level. It's about 4' below grade along two walls.
We tore out the old walls, and near one of the windows, there's a section of blocks about 24" wide where the mortar is cracked. A couple of the blocks are a bit above grade, and even though the cracks are narrow (less than 1/16"), you can see light through them from the outside.
What is the best method for repairing these cracks?
Landscaping is sloped well, but these blocks are located directly below a silcock for a water hose connection outside. I suppose that this is partially responsible for the cracking. Anyway, I need to have these blocks waterproofed pretty well since they'll likely be exposed to lots of water in the future.
We tore out the old walls, and near one of the windows, there's a section of blocks about 24" wide where the mortar is cracked. A couple of the blocks are a bit above grade, and even though the cracks are narrow (less than 1/16"), you can see light through them from the outside.
What is the best method for repairing these cracks?
Landscaping is sloped well, but these blocks are located directly below a silcock for a water hose connection outside. I suppose that this is partially responsible for the cracking. Anyway, I need to have these blocks waterproofed pretty well since they'll likely be exposed to lots of water in the future.
#2
09-12-11, 03:50 PM
Preventing moisture problems in block walls is always best if attacked from the outside. I would locate the offending block on the outside, dig down as far as feasible, or as far as the cracks go, apply a cinder block coating and fiberglas, then more coating to ensure it is sealed. After a few days, you can back fill and taper your landscape back properly.
#4
09-23-11, 09:01 AM
Join Date: May 2010
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I'm going to dig down and address the cracks from the outside. From what I've read in other threads, hydraulic cement might be an option.
As I understand it, you open up the cracks a little bit more in a dovetail shape, then apply the cement and let it expand. Can someone describe the dovetail joint a bit more?
As I understand it, you open up the cracks a little bit more in a dovetail shape, then apply the cement and let it expand. Can someone describe the dovetail joint a bit more?
#5
09-23-11, 10:05 PM
Sounds to me that you would want to chip an inverted V so that the deeper into the block the wider the opening to allow the hydraulic cement to expand and not push out of the crack.
#6
09-24-11, 04:12 AM
IF your cracks are large enough to utilize hydraulic cement. They may not be. If not, a solution as stadry1 suggested would be the best overall solution. It would make the entire wall waterproof and help shed water away from the entrance points.
