The engawa (縁側) is a functional space in traditional Japanese wooden architecture. It is an inbuilt ground floor veranda, facing garden or backyard, which can be opened to let sun into the house on cold winter days, and screened in summer to stop overheating the interiors. 
On the second or third floor of a home it becomes a sort of service corridor or built in sun room, and many people have fond memories of watching fireworks in summer with the engawa thrown wide open.
To really fine tune the amount of light, air, noise, wind, sun, insight, you let in to the house (or the engawa space alone) it usually has multiple set of various types of doors and several levels of windows high and low.
All year around, the engawa becomes a practical space that elegantly ties in the backyard or garden with the interior of the house.
All engawa comes with some form of insect repellant incense holder, the most popular one for the last few centuries has been the iconic katoributa (蚊取り豚), most homes have this, and you can get lightweight ones for camping or outdoor events.
The furin (風鈴), wind chime, is a classic summer item for the engawa. It's soft chime tells you when there is a cooling breeze. The psychological effect is so strong that some people feel cooler just from hearing the sound. It is often in glass, sometimes in bronze or clay.
