Stain under windows.

[peter101]

Stain under windows.

After winter, the bricks under windows have white powder (efflorescence) as shown on the photo.


When I bought the house last year and some contracts told me it was because the window seals had a lot cracks and the water enter the wall through the cracks. So, I redo all window caulking last year, but the problems are still not solved.
Now some contracts told me I have to repoint the brick joints under the windows to solve this problems.
I would like to get your opinions. Thanks.

 

[nealtw]

Peter; I've look at you photo a few times, and I'm still looking at windows. Have they been changed and are they new vinyl in old wooden frame?

 

[Mightygiving]

The fact that efflorescence appearing requires copious amounts of water pass from behind the mortar and weep through that mortar outward, would give creedance to what the new contractors are saying. To get a better idea if that is infact the need, remove the screen and lean out over the sill and look at what the mortar around and below the concrete sill looks like and take a screwdriver and scratch it in several places to see if it has lost the concrete bonding.

If the mortar is deteriated and possibly the top surface of the sill is massively pitted (which weather,pigeon/bird feeces will cause) loosing its water cast off ability and depending on the slope of that sill (might have settled leaning inward) allowing that waterflow to go behind the brick facing. If this is the case, a greater question might become, what has happened to the substrate(s) behind the brick and the potential of rot in those materials (sill plate, cripples, wall plate at the floor and subflooring under the window area).

 

[JoeD]

Definitely water intrusion. Based on where the stains are I think the intrusion is coming from above the sill. The mortar below looks damaged but I don't think it is the cause of the problem. I think it is the result of the problem.

 

[peter101]

Peter; I've look at you photo a few times, and I'm still looking at windows. Have they been changed and are they new vinyl in old wooden frame?

Yes. It is old wood fram cover with thin metal sheet. When last year doing window caulking, some of the bottum fram were found rotten, but window now is sealed well.

 

[peter101]

The fact that efflorescence appearing requires copious amounts of water pass from behind the mortar and weep through that mortar outward, would give creedance to what the new contractors are saying. To get a better idea if that is infact the need, remove the screen and lean out over the sill and look at what the mortar around and below the concrete sill looks like and take a screwdriver and scratch it in several places to see if it has lost the concrete bonding.

If the mortar is deteriated and possibly the top surface of the sill is massively pitted (which weather,pigeon/bird feeces will cause) loosing its water cast off ability and depending on the slope of that sill (might have settled leaning inward) allowing that waterflow to go behind the brick facing. If this is the case, a greater question might become, what has happened to the substrate(s) behind the brick and the potential of rot in those materials (sill plate, cripples, wall plate at the floor and subflooring under the window area).

the mortar below the concrete sill is damaged and loose. But, we have seal all the window frame and no water will go in between the sill and fram. You mean the sill has to change.

 

[nealtw]

Is the bottom surface of the stone sill sloped down away from the building or does it have a drip edge cut into it? If not water can kling to it and travel back to the brick.

 

[Mightygiving]

the mortar below the concrete sill is damaged and loose. But, we have seal all the window frame and no water will go in between the sill and fram. You mean the sill has to change.

It isn't a problem with the window frames it is a problem with the sill's surrounding mortar and that isn't sealed it needs repointed because it has FAILED thus letting water in via cracks, separations and where it has washed out from the water pushing it out.