I am trying to find out the proper transition from a wall to a chimney bumpout. My sisters house is getting water coming in around the fireplace when there is heavy blowing rain. The fire place was added to the house by the previous owners after the house was already built. The house has vinyl siding. So there is a vinyl siding wall and it is finished with j channel and then the brick for the chimney. I already fixed the flashing on the roof where water was coming in there. But I am not sure the proper way to tie a wall into the brick under the siding to keep water from penetrating. Any help would be appreciated.
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Is the brick tight against the sheathing or is there an air space?
The brick is tight against the sheeting.
The best thing to do would be to step flash the bricks to the wall. Chip or grind out the mortar 4" out from the house, and let in 7x7 step flashing.
If I understand correctly, you've got vinyl siding running into a brick chimney which creates a verticle joint where the water is intruding.
I've not dealt with vinyl in this situation, but with wood or hardie siding we install an "ell" shaped piece of flashing nailed to the wall sheathing and laying against masonry. We bend a "kick" on the exposed, hemmed edge so it lays tight against the brick about 2" proud of the sheathing. If the brick is irregular, we lay a bead of caulk on it, under the flashing before installing. Then the siding is installed.
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We have found almost every wall behind these types of chimneys damaged because of leaks like this.
I like "seeyou"s idea of how to install the flashing but I think you should always lay the outer edge in a hefty bead of caulk.
Thanks for the responses. I think I will follow seeyous idea of flashing with caulk behind it. It is amazing the amount of water that has gone through this joint. It has ruined drywall in the second floor, first floor and is running down the basement wall. It has also caused mold to grow in the insulation. A huge job that probably could have easily been prevented in the first place.