This is a very interesting request. There are many houses in the novel. Let me give you a few of the most important ones. The first description of note is of the Radley house. Scout gives her impression of the house.
The Radley Place jutted into a sharp curve beyond our house. Walking south, one faced its porch; the sidewalk turned and ran beside the lot. The house was low, was once white with a deep front porch and green shutters, but had long ago
darkened to the color of the slate-gray yard around it. Rain-rotted shingles drooped over the eaves of the veranda; oak trees kept the sun away. The remains of a picket drunkenly guarded the front yard— a “swept” yard that was never swept— where johnson grass and rabbit-tobacco grew in abundance.
There is also a very sparse description of Atticus' office.
Atticus’s office in the courthouse contained little more than a hat rack, a spittoon, a checkerboard and an unsullied Code of Alabama.
The courthouse is further described:
Because its primary reason for existence was government, Maycomb was spared the grubbiness that distinguished most Alabama towns its size. In the beginning its buildings were solid, its courthouse proud, its streets graciously wide.
Finally, here is a description of the Finch family home:
At the end of the road was a two-storied white house with porches circling it upstairs and downstairs. In his old age, our ancestor Simon Finch had built it to please his nagging wife; but with the porches all resemblance to ordinary houses of its era ended. The internal arrangements of the Finch house were indicative of Simon’s guilelessness and the absolute trust with which he regarded his offspring.