Sitting behind Twin Pines, the Modular is used as volunteer staff temporary housing during summer sessions. It has also been used for lease group staff when Camp Arbolado had a formal science camp with various school districts. The Modular has three bedrooms that can hold a total of 10 people, a large living room, a large kitchen, a utility area with a clothes washer and dryer, and two indoor bathrooms. Modular is one of the newer buildings at camp, prebuilt and brought up to camp in 1992 in two sections, which were joined and connected in the middle once they were secured to the pad.

Below are photos of Modular through the years.