Porch Rot: How $2.00 in Flashing Could Have Saved $150,000 in Repairscomments (10) February 3rd, 2011 in Blogs
Several months ago we were completing a custom home on Florida’s Gulf Coast. A neighbor who was impressed with our clean and organized jobsite asked us to look at a leak in their exterior balcony. The house was three years old. It included two living floors over a garage level and had balconies on two sides of both the upper floors.
What was visible at the time was a small hole in the drywall ceiling above the ground floor where water would drip after a rain, and crack lines in the stucco on the columns and along the beams. (see photos). These were different from normal shrinkage cracks. The stucco surface showed signs of displacement due to swelling. We have done repair work on a number of similar projects. Our experience has been that the size and displacement of the cracks are signs that water has been trapped in the wall behind the stucco. The wet sheathing swells and the wire lath rusts, causing the cracks to appear.
In this case, the owner had already hired an inspector who took pictures showing clean, dry plywood in the deck. We had hopes that the damage might have been caught early and that we would not have to do major structural repairs. Even so, we knew from past experience that hidden damage can be extensive. We proposed to do an investigation consisting of removal of drywall around the leak, loose tile above the leak, and stucco at the worst of the stucco cracks. Based on our findings, we would recommend a repair plan.
When we removed the drywall ceiling, we saw that the plywood along the outside edge of the deck was completely stained with water and mold. When we removed the tile above that area and probed the plywood decking, it was so badly rotted that I was able to stick my pocket knife completely through the deck with no more resistance than if it was Styrofoam (see photos). Apparently, the tile on the balconies had come loose shortly after the owner moved in. The contractor sent someone to remove the tile and re-install it. Whoever did the work used a grinder to cut through the tile joints. They cut through the fiberglass waterproofing at almost every joint.
We removed stucco from a column and a section of beam where the cracking was pronounced. We found that the flashing on the edge of the decks stopped at each side of the column. Water had entered the boxed out framing around the column and spread laterally into the beam. Fortunately, the six by six columns were pressure treated and were still intact. (See photos).
posted in: Blogs, water and moisture control, porch
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