Wood rot is frequently found in door thresholds, kick plates and the surrounding trim. The rot is caused by too much water that splashes up from the landing immediately below the door. When the water doesn't dry right away, i.e. if it finds its way into cracks, that is when wood rot starts.
Building codes require all exterior doors to have a landing for safety. This landing is typically only 8 inches below the door threshold so it's easy to see how it can splash up and hit the house. The problem is compounded by water running off the roof, so much more water hits the landing and potentially splashes back against the door and house.
Front Doors and Wood Rot
Front doors are more vulnerable as they're seldom used and most home owners don't notice problems right away. The home owner of the front door shown here found the wood rot when she started to touch up the paint on the trim around the front door. The more she poked, it quickly became apparent that the problem was serious and she called my handyman company.
This owner was being conscientious in painting the trim around her doors and windows. The house was only 5 years old and unfortunately the problem was due to improper flashing during construction, compounded by the first home owner not focusing on home maintenance for a brand new house.
Many people forget that exterior paint's first priority is to protect your home from water damage. When the wood isn't sealed (caulking and paint) properly, the wood absorbs water and this moisture enables fungi to live. The fungi breaks down the wood fibers and decomposition occurs and may not be invisible to the human eye for quite some time. The moisture can travel up the kick plate under the door to reach the threshold, and may extend to the vertical wood trim and door jambs sitting on top of … and touching the threshold.
When my company made repairs to this front door, on a 5 year young house, we found extensive wood rot requiring the following repairs:
- Siding removed and sheathing behind replaced.
- Front door, threshold and kick plate all had to be replaced (we did try to save the door but found wood rot underneath the weatherstripping at the bottom).
- Our home owner chose to replace all trim surrounding the door using Azek, a composite with no wood content, to avoid future problems.
Wood Rot and Sliding Patio Doors
Patio door problems have similar problems but quite often, they're not from splashback. Wood rot problem with patio doors are frequently due to the ledger board not being installed properly. The ledger board is used to attach a deck to the house. It needs to be flashed to keep water from getting behind the board where water can collect and create an environment for fungi to thrive. This moisture can travel up the siding and sheathing on the house above and/or below the deck surface., and may take years for the rot to be visible.
The photo above illustrates the tip of the iceberg. My handyman company spent a week at this customer's home replacing a significant amount of structural wood, insulation, plywood sheathing and siding running about 8 ft back from the patio door. The technician also re-framed the door, replaced the threshold and replaced rotted deck boards.
The home owner had just retired and was shocked at the extent of the damage. He had owned the house for twenty years and never knew he had a problem. He uncovered it while reviewing the repairs needed before putting the house up for sale. Where he originally thought he could get the house ready to put on the market by himself, this one project turned into 6 days for one of my most skilled technicians to handle the repairs.
Read the rest of our series on water damage and wood rot repairs …
- Water & Wood Rot Repairs – Roof
- Water & Wood Rot Repairs – Siding
- Water & Wood Rot Repairs – Windows
- Water & Wood Rot Repairs – Doors … this article
- Water & Wood Rot Repairs – Decks
- Water & Wood Rot Repairs – Exterior Trim