Bullfrog Birdhouse Pattern

Why is the right side piece of the roof, Item “E”, 1/4” longer, front to back, than the left side piece, Item “D”?

The “Bill of Material” lists the dimension’s for the roof as::

Item D 3/4” x 7-3/4” x 8-1/4”
Item E 3/4” x 8-1/4” x 8-1/2”

Item E will overlap Item D at the peak of the roof so it needs to be 3/4” wider right to left than Item D, as you’re looking at the pattern. My pieces match the dimensions of the pattern. However, front to rear, Item D and E should match, but Item E is 1/4” longer than item D. Why???

Thank You
Jeff

I made this for my sister and she loves it!!

Not used it yet should work ok . Thanks