Why Do Doorjambs Rot?

Q: I’m a realtor and almost half the WDO reports my customers get back have rotten door jambs. This seems such a common issue, can it be prevented?

A: The issue you describe is common. The challenge is a combination of the products installed by builders and Florida weather. The typical ‘builder grade’ door is made with pine door jambs. This solution is inexpensive, but is not appropriate for our humid environment and afternoon showers. You must keep pine sealed with paint or it rots quickly.

Yet, this grade of door is used on 90+% of new construction, and it’s the same inexpensive door that many purchase off the shelf at the large home supply chains to replace what they have. Fiberglass jambs are weatherproof and should theoretically last forever, but they cost more. For many, cheaper is always better, and so the issue persists.