To find the perimeter of the backyard, we need to know the total length of the yard's boundary. Since the layout is made of two rectangular sections, we'll calculate the perimeter by adding up the lengths of all four sides. However, I would need the specific measurements (lengths and widths) of the two sections of the backyard to proceed.

Could you provide those details, or if you have a diagram, you can upload it here? That way, I can assist with the exact perimeter calculation.