Sketches without Shades & Shadows
There are times when shades and shadows in a perspective sketch are not necessary. Shading will enhance the 3D image of your sketch, but sometimes it will obscure the details that is essential for the mood of your sketch. Shadows from multiple lighting directions could also cause the details to loose clarity.
Sketchingjourney's Blog 
Cool sketch!! Indoor/outdoor effect that’s impossible to capture with a picture.
Thank you for your very interesting comment and observation. Although I used this sketch to comment on shades and shadows, the purpose of the sketch was to illustrate the flow of spaces between the family room (behind the outdoor furniture), the kitchen (behind the Aeron chairs), the living room and the outdoor patio. Discovering the view took longer than the time to do the sketch!