| I've been using and recommending DAP Dynaflex caulk for many years -- since it was called Formula 230. I like it because it remains flexible for a long time, preventing cracking along the sealed seam. But, I must now face the fact that is seems to be an aggressive growth medium for mildew. |
In the following pictures the dark/black caulked areas are mildew -- not grime.
| In each case when I rework the seam, I scrub it with a toothbrush and TSP solution. I follow this with a bleach solution. I then prime the area with Zinser 123 primer, and top it with two coats of Pratt-Lambert Accolade. All in an attempt to prevent the mildew coming back. But, to no avail. |
The seam in this next picture has been redone three times. Most recently about three years ago.
The following seams have been redone twice
This seam is the joint between two 4x8 pieces of wall paneling
