A Shop-Built Bay Window

The "ridge" is screwed to the tops of the common rafters.

The ends of the nailers stuck out beyond the edge of the subfascia, which put the edge of the nailers above the roof plane. The height of the plumb line on the nailer where it overhangs the framing equals the amount the nailer needed to be “dropped” so that its inside top edge would be in plane to catch the roof sheathing.

About 3/8 inch along the heel cut would be trimmed off.

Once cut, the nailer is installed at the proper height.

A framing square was placed on the ledger and used to mark the location of the "jack rafters" on the nailers.

The length of the "jack rafters" was taken directly from the roof assembly.

The roof sheathing sections were cut and temporarily tacked onto the bay roof on the bench.

The sheathing was removed and set aside to be installed on site.

The template was used to lay out the profile of the angled corner posts, and the dimensions were transferred to a section of 2x4. For each post, a bevel was ripped on one side of a pair of 2x4s.

The pairs of beveled 2x4s were screwed together to ensure a straight corner post.

On site, after a new 1x4 bottom plate was nailed to the existing sole plate, the angled corner posts were toe-nalied to the plates.

A 2x4 plate is nailed to the tops of the posts for setting the roof.

At 50 pounds, the roof assembly was easy to lift into place.

The corners of the top wall plate bisected the angled lookouts. The wall was positioned, plumbed, and secured to the center ceiling joists.

Blocking and sheathing were nailed to the framing, and sill pans were installed.

The windows were set level and plumb to the openings and to each other.

The bay was trimmed with cellular PVC stock.

The drip edge and step flashing are attached with copper roofing nails. Note that the roofing membrane is turned up the wall underneath the flashing.

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