Skip to main content
Stesso
BrowseFeedExpertsMy Projects
Log inSign up
Stesso

Step 7 · Install Remaining Flashing and Sealant

If the window has a nailing fin, apply flashing tape over the top and sides of the fin, ensuring it overlaps with the previously installed flashing. Then, apply a continuous bead of high-quality exterior-grade sealant (e.g., silicone or polyurethane caulk) around the entire perimeter of the window where it meets the exterior siding or trim. This seal prevents water and air infiltration. Smooth the bead of sealant with a wet finger or tooling tool for a clean finish.

Stesso home
SearchSearchBrowseBrowseFeedFeedMy ProjectsMy Projects
Log inLog inSign upSign up

Step 7 · Install Remaining Flashing and Sealant

If the window has a nailing fin, apply flashing tape over the top and sides of the fin, ensuring it overlaps with the previously installed flashing. Then, apply a continuous bead of high-quality exterior-grade sealant (e.g., silicone or polyurethane caulk) around the entire perimeter of the window where it meets the exterior siding or trim. This seal prevents water and air infiltration. Smooth the bead of sealant with a wet finger or tooling tool for a clean finish.

Videos for this step

Flash Flanges and Final SealApply Exterior SealantSeal Exterior of Window

Tools and Materials

← Project

Window Installation

Step 7 of 8·1.2 hr left

Inspect and Prepare the Rough Opening
30 minutes6 items
Apply Flashing Tape to Sill
15 minutes3 items
Apply Flashing Tape to Jambs and Head
20 minutes3 items
Position and Set the Window
25 minutes4 items
Shim and Level the Window
40 minutes6 items
Fasten the Window Frame
30 minutes4 items
7
Install Remaining Flashing and Sealant
25 minutes5 items
8
Install Interior Trim and Finish
45 minutes8 items
Prev
Next
TermsPrivacySafetyLegal© 2026 Stesso, Inc.