I noticed a horizontal crack along the mortar joint between the two stones on the exterior of the house and believe that spot is also leaking water into the house when rain hits hard on that surface.

I’m looking for suggestions on how to repair the crack without costing a fortune. How do I make sure whatever gets filled matches the same colour as the rest of the existing mortar? Is there anyway to also make it waterproof so it doesn’t leak again in the future?

  • If that is the only spot, could you get a photo of the surrounding area? The crack may mean nothing depending where it is on the wall. FWIW, all masonry is porous, it does allow moisture through the wall. The most important aspect of the wall assembly is the weatherproofing layer, typically tar paper, in older homes. It is not the stone facing. The stone protects the tar paper. A small crack like that? I would not be concerned with in the way of moisture infiltration regarding the nature of masonry to begin with. I would be more concerned why the crack is there to start with.
    – Jack
    Oct 16 at 15:12
  • Unfortunately I don’t have any other pictures but location wise, this is the front of the house right beside the second floor window. The surrounding area looks exactly the same, without any cracks. I originally had a leak that I thought for sure was coming from the roof, but after several roof inspections it was not the case. Then one day I hosed the crack and water started coming in to the first floor ceiling. I’m guessing water travelled and found it’s way to the first floor ceiling. Would you know why this is the case and how I can go about fixing it so it doesn’t leak again? Oct 17 at 14:36
  • I will not be able to speculate how the water got to the first floor ceiling if the waterproofing layer is doing what it is supposed to. Perhaps the volume of water that was getting into the crack being forced in by the hose was more than it supposed to handle. Rainfall I am sure will not drive in the way that hose was doing. One question for you, is the brick facing a veneer over framing or is the home full masonry, as in the brick is backed by more masonry, and the drywall on the inside is attached to firring strips instead of 2X framing?
    – Jack
    Oct 18 at 3:31

Cold chisel out the cracked mortar, get a grout bag and push mortar back into the joint, tool it to look the same.

There will likely be a color difference it just isn't possible to match weathered mortar perfectly. Is this in a high visibility location - like right next to the front door that everyone sees everyday?

If you want it to perfectly match you could grind out a thin amount and apply a thin coat of mortar everywhere. It would be a lot of work. Depending on how the patch looks you might be able to wire brush the mortar near it to blend it in - depends if the patch is darker / lighter and how the wire brush changes the color of the mortar.


Fill the cracks with concrete/cement colored caulk. I have also used white caulk and wiped a little dirt on it with a finger, looked very good.

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