Drip Caps
Definition and meaning of Drip Caps in real estate.
Drip caps are L-shaped metal or plastic flashing strips installed above windows, doors, and exterior trim to direct rainwater away from the building envelope. They prevent water from seeping behind siding and causing structural rot.
In more detail
Rainwater running down a building's exterior can easily penetrate the small gaps above doors and windows. Drip caps are mounted flat against the wall sheath beneath the weather barrier, with a projecting lip that extends over the top of the trim. This design uses gravity to shed water outward, preventing leaks that can damage framing, drywall, and insulation.
Properly installed drip caps are a vital component of a home's moisture protection plan and are checked during structural inspections.
Key facts
| Category | Property Types & Construction |
|---|---|
| Primary Function | Redirects water away from exterior openings |
| Installation Location | Above doors, windows, and horizontal trim |
| Common Materials | Aluminum, vinyl, and copper |
A builder installs an angled aluminum strip over a new front entry door frame before applying the exterior siding to shield the door trim from water intrusion.
Frequently asked questions
Are drip caps required by building codes?
Yes, modern building codes in most jurisdictions require drip caps or equivalent flashing above exterior windows and doors to prevent moisture damage.
Can you add a drip cap after the siding is installed?
It is possible, but retrofitting is much more difficult because the flashing must be tucked carefully underneath the existing siding to work correctly.