Windows – Exteriors and Outdoor Design (2) : Design trends for exterior spaces and four-season rooms

windows should allow both light and the outdoors into an interior space as well as combine energy savings and security with the architect’s imaginative architectural aesthetic.

We continue our educational series with:

Windows connect the interior of a house to the outdoors, providing ventilation and daylight, additionally they are a very important aesthetic element to your design.

In many cases windows are the architectural focal point of a residential design.  That being said, it is also important to focus on the energy savings from a window system. Although the thermal efficiency of windows has improved markedly, it is crucial for today’s architect to select good quality windows, shopping wisely for the best combination of price and thermal performance.


Windows and window systems are available in various styles and sizes and can be customized to fit your project’s specific design.  Options include:

  • Fixed, casement (in or out-swing)
  • Hopper
  • Awning
  • Sliding
  • Lift & Slide
  • Tilt & turn (inswing only).

All window systems are available in aluminum, thermally broken, and wood with clad interior and all are available in radius or arched frames as well as traditional orthogonal design.  Special features include concealed hinges as well as custom finish options including wood cladding with options of a large variety of wood types which include:

  • Pine
  • Poplar
  • Alder
  • Bamboo
  • Birch
  • Cherry
  • Douglas Fir
  • Mahogany
  • Maple
  • Oak
  • Zebra
  • Walnut
  • Sapele Mahogany
  • Brazillian Cherry
  • Black Walnut
  • African Mahogany
  • Honduran Mahogany
  • Brazillian Walnut
  • Lyptus
  • Red Oak
  • Knotty Pine
  • Black Palm


In climate zones of the country such as California, Nevada and Arizona where cooling is the major energy use, it is important that the windows reduce their solar heat gain. The Solar Heat Gain Coefficient (SHGC) is the fraction of incident solar radiation admitted through a window. SHGC is expressed as a number between 0 and 1. The lower a window’s solar heat gain coefficient, the less solar heat it transmits. All climate zones of the country benefit from reduced solar heat gain on the east and west facing windows because the heat gain for heating reduces the heating energy requirement less than the cooling energy requirement.

There is a tradeoff between solar heat gain and visible light transmission (an optical property that indicates the amount of visible light transmitted). There is also a tradeoff between the solar heat gain coefficient and the amount of passive solar heating of the house.

The benefits of thermally broken aluminum windows include warmer winters, cooler summers, and a more comfortable living environment. The design of a thermally broken aluminum window includes a polyamide (1) insulator between inner & outer aluminum faces. The result is a permanent thermal barrier that effectively fights energy transfer between the inside and outside and vice-versa.

Clear Low-E (2) tempered 1″ Insulating Glass (3)is the standard. Various types of glass and other materials at a thickness of up to 2″ may also be used.


Another major concern in selecting proper windows for any design is security.  All operating windows should have at the minimum stainless steel multi-point locking systems for increased security over a single point locking mechanism. The Tilt & Turn window offers ventilation when in the tilt position while still providing intruder resistance.

(1) – A polyamide is a type of plastic having high heat resistance.

(2) – Low E is a film coating that reflects radiant infrared energy, which is meant to keep the energy on the same side it originates from while still letting in visible light. So, when the sun shines, a Low-E coated window reflects a lot of that unwanted energy back towards the sun instead of letting the heat pass through the glass.

(3)  Insulating glass (IG) is more commonly known as double glazing (or double-pane, and increasingly triple glazing/pane). IG consists of two or three glass window panes separated by a vacuum or gas filled space to reduce heat transfer across a part of the building envelope.

We hope you gleaned some valuable information from the second installment of our educational series and we also hope you tune in for next month’s installment focused on French Door systems.

French doors can serve as both entry doors and as views to the outside. They are also ideal to create a smooth flow of pedestrian traffic between the outdoors and indoors …

Thank you again for going through our educational series titled:
This material is based on our AIA accredited CEU course offered both online and in live sessions during our lunch and learn presentations. If you would like to schedule a live CEU AIA accredited Lunch and Learn Course for your office simply email and indicate your interest in a specific date and we will contact you right away.

Learning Objectives – After this course, you should be able to:

Discuss the key sustainability criteria (LEED and SITES) that apply to the design of exterior spaces and outdoor rooms.
Describe some of the various product systems that are available for designing exterior spaces and outdoor rooms, and understand each system’s compliance with sustainability criteria.
List design options for exterior deck spaces regarding railings and safety.
Explain the ways in which exterior spaces and outdoor rooms can help to meet LEED and SITES requirements of human health and well-being.

If you would like to take the official course for actual CEU learning credits CLICK HERE


  • 1.5 AIA LU/HSW
  • 0.1 IACET CEU
  • AAA 1 Learning Hour
  • OAA 1 Learning Hour
  • May qualify for 1 AANB Learning Hour
  • SAA 1 Learning Hour
  • MAA 1 Learning Hour
  • AAPEI 1 Learning Hour
  • May qualify for 1 NSAA Learning Hour
  • AIBC 1 Learning Hour
  • NLAA 1 Learning Hour
  • NWTAA 1 Learning Hour