Graduate School of Architecture, Planning and Preservation

A4220 - Enclosures and Environments I                                                                        

Instructors        :  Tony Webster, Mayine Yu

T.A:  Jennifer Gellin                                                               Thursdays, 2-6 PM, 114 Avery

Course Description

The course begins with a brief historical introduction to building envelopes.  The evolution of the building envelope is outlined in terms of: the functions it performs; atmospheric conditions it mediates between, its relationship to other building-perimeter systems, and the principles of physics and properties of materials employed to perform its functions.

The environmental forces acting on envelopes are outlined.  The performance criteria of contemporary enclosures is presented, including environmental separation, filtering, buffering, and structural participation.  Envelope design criteria, and its relationship to performance criteria, is discussed.

Specific architectural strategies for separating conditioned spaces from the outdoors are covered in depth. Various envelope strategies are presented as they emerged historically. For each envelope system studied, the relationship between the building envelope and other building perimeter systems is discussed.  The physical properties of the building enclosure's components, manufacturing and construction constraints, and the mechanical behavior of each component is outlined.  In addition to explaining how building envelope systems work through case studies, the technological and economic forces driving their development are explored.

Finally, the use of envelopes and partitions for fire safety is traced historically, and contemporary approaches are detailed.

Both design projects and case-study analyses are given throughout the semester in the form of homeworks.  In addition to their use in building the students' understanding of building envelopes, these exercises illustrate how technical-utilitarian systems have been used to create tectonically striking structures, and they encourage students to consider the potential of technical-utilitarian systems to inform the spaces and formal expression of their own designs.

Included Topics

The Evolving Concept of Shelter

.           Rain and snow, wind, temperature, humidity, security and electromagnetic shielding.

            Building Envelope vs Building Perimeter

.           The relationship between the building's skin, structure, and environmental conditioning systems.

            Contemporary Envelope Design Criteria

.           Strategies for deciding what has to be done, and what else could be beneficial.


Environmental Forces on the Building Envelope

The Sun, the Earth and Its Atmosphere

Physical Properties of Building Components and Atmospheres

Strength and Stiffness

Water Resistance

Thermal Expansion, Thermal Resistance, Thermal Capacity, Thermal Feel


Changing States

Mechanisms of Heat Transfer




Human Comfort



Water And Air Movement Across the Building Envelope

Design Goals:

.           Water out, fresh air in, pressure differentials, H2O vapor constrained

Air and Water Physics:

.           Requirements for H2O to cross the envelope

.           Forces moving H2O through envelope

.           Forces moving vapor through the envelope - the dew point disaster

Design Strategies:

.           Controlling vapor movement

.           Maintaining pressure differentials

.           Water barriers and rain-screens

Heat Flow Through the Building Envelope

Design Goals:

.           Maintaining the thermal comfort zone

Design Strategies

.           Geometric effects.

.           Earth and atmospheric boundaries (walls, roofs and foundations).

.           Using radiation, conduction, convection, thermal capacity, changing states, inductance to your advantage.

.           (Trombe walls, water tanks, buffers, reflecting pools, exterior insulation).

Determining External Thermal Loads on Buildings (R-Values and Etc)

.           Cooling Loads

.           Heating Loads

Structural Functions of the Envelope

Resisting gravity and wind forces


An Historically Organized Survey of Wall Systems

In each case, how they perform (or don't perform) structural functions, create water, pressure, and vapor barriers, allow air exchange, and moderate atmospheric temperatures is discussed.  Case studies are used to develop an understanding of each envelope scheme.  Systems covered include:

Monolithic Walls

            Masonry and bearing wall construction

Cavity walls

            The first rain-screen principle system and platform frame construction

Frame and Infill

            Starrett-Lehigh to Battery Park City

Frame and Exfill

            Cantilevering the rainscreen


            Inventing a new structure for the facade system

Design Project
Design and construction of a portion of a building façade

During this three-week design project, four-student groups design in detail a portion of a façade, which is technically based on one of the types studied in this class.  After a team of technically-oriented architects gives limited crits, each group constructs their design at full scale (1/4 scale for curtainwall projects).  Final work, including models and design documents, is presented in a final review of design and technology faculty and practitioners.

Field Trips

Two buildings in construction.


A passing grade is obtained by earning an average of 70% or better on the course assignments (listed below), with an overall average as follows: P- 70-75%, P 76-95%, P+ 96-100%.

  •   All homeworks (check plus = 100, check = 85, check minus = 50).
  • Group homework projects
  • The averaged homeworks, group homework, and the group project are weighted equally.

    Required Text

                Fundamentals of Building Construction: Materials and Methods, Edward Allen.        

                2nd or 3rd Editions, available at CU Bookstore.

                Enclosures and Environments I Reader, issued at cost.

    Recommended Texts

                Architectural Graphic Standards, Ramsey & Sleeper, 10th Edition, available at CU Bookstore.

                Building Construction Illustrated, F. Ching, 2nd or 3rd Edition, available at CU Bookstore.

                The Details of Modern Architecture, 2 vols, E. Ford, MIT Press, available at CU Bookstore.

                Heating, Cooling, Lighting : Design Methods for Architects, N. Lechner, Wiley, CU bookstore.

                Building Control Systems, V. Bradshaw, 2nd edition, Wiley, available at CU Bookstore.


    Required and recommended texts will be on Reserve in Avery, as well as:

    Esmond Reid, Understanding Buildings: A Multidisciplinary Approach, MIT Press.

    Edward Allen, Architectural Detailing: Function, Constructability, Aesthetics, Wiley, 1993.

    Edward Allen, How Buildings Work, Oxford, 1980.

    Aluminum Curtain Wall Design Guide Manual, American Architectural Manufacturers Association, Des Plaines, IL, 1979.

    Ambrose, Building Construction and Design, VNR, 1992.

    Brookes and Grech, The Building Envelope, Butterworth.

    David Guise, Design and Technology in Architecture, VNR.

    Carl Bovil, Architectural Design: Integration of Structural and Environmental Systems, VNR.

    Tech Topics, Progressive Architecture, 1992 -- 1996.

    Brand, R., Architectural Details for Insulated Buildings, VNR.

    Goumain, P, ed., High Technology Workplaces, VNR.

    Cowan, H., Handbook of Architectural Technology, VNR.

    Olin, H., Construction, Principles, Materials and Methods, VNR, 1991.

    Packard, R., ed., Architectural Graphic Standards, Wiley.

    McGuinness, W., Building Technology: Mechanical and Electrical Systems, Wiley.

    Kurzweil, The Age of Intelligent Machines, MIT Press

    Rush, R., ed., The Building Systems Integration Handbook, 1990, ISBN 0 7506 91998 0

    Forester, The Materials Revolution, MIT Press, 1988.

    Danz, The Architecture of SOM 1950-1962.

    Elliot, Technics and Architecture, MIT Press, 1992.