How To Flash A Window To Vinal Siding Exterior Wall

Cut the drip cap to the correct size for your window.

How to flash a window to vinal siding exterior wall.

Hold the panel under the window and mark the width of the window opening on the panel. Install the water resistant barrier to overlap the top edge of the weep screed. Do not cut the vinyl off. All flashings must integrate with adjacent materials so water always flows to the exterior following the shingle principle.

Apply a bead of caulk to the felt and set the window in the caulk. 1 2 inch 1 3 cm plywood or osb are common substrates and these are generally covered with roofing felt or another moisture barrier prior to siding the walls. Install the trim just under the drip cap. To mark the vinyl panel to be cut follow the steps below.

Use a siding removal tool. Attach the flashing tape above the window and then slip the drip cap into the siding and attach to the tape. You want to make sure you are sloping the cap away from the window so that any water will run off. Where a slope roof meets a sidewall slip the upper legs of the step flashing under the sheathing wrap see illustration.

Extract nails keeping the vinyl pieces in place in order to prepare vinyl pieces to be removed. Install the lathe and stucco to the first bend in the weep screed. If you ve added wooden trim around the window the cap flashing goes over the wood trim. Since vinyl siding can expand and contract depending on the outdoor temperature fitting siding under windows requires careful measuring and planning.

This helps direct water out away from window. Use this tool by inserting it where a piece of vinyl overlaps a piece below it and then sliding it across until you reach the end of. Estimate the quantity of vinyl siding needed. Do not exclude window and door cutouts since this provides needed excess materials.

Click to enlarge make sure the sheathing wrap overlaps all step flashings. Remove the pieces of vinyl siding from around the window area. For example if you locate an interior stud 12 inches from the corner add the thickness of the drywall usually 1 2 inch plus the thickness of the studs which is 3 1 2 inches if the studs are two by fours. At the top tuck metal drip cap flashing under the siding and on top of the second layer of wrap.

In this type of installation seal the cap flashing directly to the sheathing with high quality sealant. Multiply width and height to arrive at the square footage. Next comes another layer of building wrap installed like the first layer. Then place the top piece of flashing tape over the cap flashing and layer the house wrap over the tape.

Remove any siding or exterior finish that isn t compatible with vinyl siding and make sure the walls are sheathed with a substrate to receive the siding. Measure the width and height of the side of the house treating the measured area as a square or rectangle.