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Exterior Window Drip Cap?

Is the window drip cap trim still something needed with "new installation" windows?

I have 1927 home. I am in the process of replacing every 85 year old double hung window with comparable (Alum-Clad Exterior, Pine Interior) new windows. I am gutting right to the frame.
The windows today have a little plastic trim lip on them. When I replace the exterior window trim, is the traditional piece of drip cap above the top horizontal trim board still necessary if everything is flashed properly?

I tried to share a pic, but attaching a file to this forum is ridiculously unaccommodating...uggh. :(

All feedback is appreciated.

Thank you.

Re: Exterior Window Drip Cap?


On windows with the integrated plastic fins, a rain cap is redundant. The fin will prevent water from working its way to the sheathing, especially when used in conjunction with a rain screen and weather shield tapes.

Re: Exterior Window Drip Cap?

Yes window head / Cap flashing is required.
Check with the window manufacture and ask for a detail for installation instructions along with the flashing details.
Also check to see if you can find a detail that does not require flashing ?
Make sure the detail you select is suited for the siding you have installed at this time.
Does the window installation require a sill flashing ?
Last ask an Architect or Engineer to draw you a detail for proper installation for the type of siding installed.

Re: Exterior Window Drip Cap?

if your talking about a metal cap flashing YES! they create a better lap over the top of the nailing flange down over the face of the brick mold. they should also fold down the side for a proper seal

sil pans arent necessaritly required but if done do not seal the bottom nailing flange.. the whole point of the sil pan is to stop any moisture that does get in to run back out without the rough sil from absorbing the moistue.. .the moisture will either from the window leaking or condesation forming on the window frame itself. just tape the sides and top, however regular siding tape wont do as it loses its tack after only a couple years

use 4" rolls of blueskin, vycor or or another other self sealing peal and stick flashing

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