Observatory Construction: Introduction

Observatory Design

Zephyr Ridge Observatory is a roll-off roof design. The building measures 20' x 32' which includes a 20' x 20' observatory room and a 12' x 20' insulated "warm room." The roof is set upon a rail system, and an electric motor moves the roof along the rails, exposing the observatory room to the sky. The building is oriented so that the roof opens to the north. The upper portion of the south wall is hinged so that it can be folded down to expose a greater portion of the southern sky.

The foundation for the building is a concrete slab. There is an isolated 2' x 2' concrete pier that is attached by rebar to the solid bedrock below, which at the pier location was about three feet below grade. The concrete pier was built to floor height, and my telescope rests on it. If ever I decide to install a permanent telescope for astrophotography, the existing pier can be augmented. Two conduits from the pier to the warm room were installed under the slab for present and future wiring needs.

The Builders

I read excellent books (see bibliography on right) about private observatories, and after considering the issues involved in a roll-off roof system, I felt it would be best to hire a builder with experience in building such structures, especially one of the size I had in mind. The local contractors I contacted had experience building houses with fixed roofs (of course!).

This is what led me to Backyard Observatories, a company from Ohio that specializes in building roll-off roof observatories (see review). They offer various roll-off roof models as off-the-shelf products, and can customize these as required. This seemed like an ideal solution, and after discussions with the owner, Scott Horstman, I hired them to build my observatory.

I acted as the general contractor for the project, coordinating the excavator, concrete workers, electrician, and Backyard Observatories.

Next: Excavation


1. Arditti, David, (2008), Setting-Up a Small Observatory: From Concept to Construction, New York, NY, Springer.

2. Hicks, John, (2009), Building a Roll-Off Roof Observatory: A Complete Guide for Design and Construction, New York, NY, Springer.

3. Moore, Patrick (ed.), (1996), Small Astronomical Observatories, New York, NY, Springer.

4. Moore, Patrick (ed.), (2002), More Small Astronomical Observatories, New York, NY, Springer.

Observatory Construction Pages

Introduction | Excavation | Foundation | Building | Afterwards | BackYard Observatories Review