Stucco chimney in Fairfax Station, Virginia
Stucco by the competition re done
18 year old chimney is a giant water sponge. The chimney has a cement basecoat and a synthetic finish. The rest of the house is EIFS.
Cracks show stains where water is coming out of the wall.
Before: The top of the chimney has a soft very porous mortar and is almost flat. Any water that runs off the top
runs right into the stone joints.
After: The top course of stone is removed and blocks put on. A band at the top forms a drip edge deflecting water
away from the chimney. The top is rounded for good water runoff, and the mortar is super hard with a chemical additive to
make the mortar less porous.
Before: Flagstone chimney shoulders are flush with edge of the stone, diverting water into the stone joints. Note the stains where water exits the stones.
After: New flagstone shoulders project past the edges allowing water to drip off away from the chimney.
The worst thing is there is no kickout flashing or counter flashing. Without a kickout flashing, water on the edge of the chimney runs into the chimney instead of into the gutter. Without a counter flashing, any water that penetrates the stucco can
run in behind the step flashing.
We cut the stucco off to expose the poorly done step flashing. A view from the top shows water funnels created in the step flashing. Also, the wall is real wet behind the step flashing.
I hope you can see this. Everything is covered with tar paper and tape. A new kickout flashing tucked behind the step flashing diverts water into the gutter. We made a conter flashing over the step flashing and overlapped the edge with new stucco.
For how we flash chimneys please click to see my 2001 article in The Stucco News
Metal corner bead was made for interior use only and has completely rusted away. Exterior corner beads aren't sold in the Washington, DC area.
Outside corners are formed with lumber and filled in solid.
A view from my scaffold is the sunrise on Occoquan reservoir in the winter time.
