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Window Orientation and Shading

Author(s)

Florida Solar Energy Center

Organization(s)

FSEC

Publication Date

October, 2022

Web article providing information on how to reduce solar gains through windows.

The overhang on the left is much wider than the window, allowing it to provide far better shade throughout the day than the overhang on the right, which is only the width of the window (results shown for south-facing window, late summer, 36N latitude).

Publication Date

Tue, 07/25/2023 - 12:00

The overhang on the left is much wider than the window, allowing it to provide better shade throughout the day than the overhang on the right, which is only the width of the window (results shown for south-facing window, late summer, 2pm, 36N latitude).

Publication Date

Tue, 07/25/2023 - 12:00

Right - Window shading is built into the south side of this home and east facing windows have been minimized to reduce heat gain from the summer sun while allowing low winter sun into the home

The 2-foot extended-width overhang on the left allows more wintertime solar heat gain to this west-facing window than the 2-foot side fin on the right (results shown for west-facing window, mid-winter, 36N latitude)

Publication Date

Tue, 07/25/2023 - 12:00

Awnings, overhangs, and porches shield windows and doors from sun, rain, and snow in this sunny mountain locale.

Publication Date

Sun, 01/01/2017 - 12:00

This house has key features to block heat such as such as tree shading for the west wall and roof, minimized west-facing windows, and a porch roof, floor, and wing walls creating deep architectural overhangs and fins to shade south-facing windows

Right - This house has key features to block heat such as such as tree shading for the west wall and roof, minimized west-facing windows, and a porch roof, floor, and wing walls creating deep architectural overhangs and fins to shade south-facing windows

Publication Date

Fri, 09/24/2021 - 12:00

The patio roof on this home provides full shade to large glass doors and windows, reducing the home's heat gains.

Publication Date

Sat, 07/01/2000 - 12:00

ENERGY STAR reflective roof shingles and low-SHGC windows with low-emissivity coatings help to minimize solar heat gain.

The Solar Radiation Data Manual for Buildings provides window overhang sizing guidance for 239 locations across the U.S.; this example is for Boulder, CO

Publication Date

Fri, 09/01/1995 - 12:00

Careful landscaping can preserve roof-top solar exposure and provide shading to help control solar gain through windows.

Publication Date

Wed, 01/01/1992 - 12:00

Clerestory windows bring light in from above, reflecting it off of surfaces, making it more appealing than the direct light that comes from skylights

Concrete slabs are used on both the first and second floors of this SIP home to provide passive solar heating from large south-facing windows.

Deep overhangs and a covered front porch provide solar window shading from high summer sun and help keep the entryway snow-free in winter.

Vertical side-shading, such as these side fins, can provide effective summertime shading for north-facing windows, but are generally not recommended for other orientations due to their marginal performance and restricted views

Publication Date

Thu, 06/22/2023 - 12:00

The design of this home incorporates multiple methods to reduce summertime solar gains including roll-down exterior blinds, wide exterior horizontal louvers, minimized east/west-facing windows, and vegetation.

Right: This house plan orients broad building surfaces away from the west and east, trees are used to shade the west and east, and large overhangs shade windows on the south wall

Publication Date

Fri, 09/24/2021 - 12:00

Porch roofs, pergolas, and large overhangs can effectively shade windows and doors facing south, southeast, southwest, or even due east or west for most of the day if the overhang is very deep and sufficiently wide.

This overhang for a south-facing window provides full shade in the summer and full sun in the winter, optimizing savings in both cooling and heating energy (results shown for 2pm in both summer and winter, 36N latitude).

Publication Date

Tue, 07/25/2023 - 12:00

The south face of this home has an overhanging second floor, a pergola, and a roof eave to provide effective window and door shading for both floors in the summer without blocking view, diffuse daylighting, breezes, or ingress/egress

An NFRC glazing system energy performance label will report U-factor, solar heat gain coefficient, visible transmittance, and air leakage; if the window is ENERGY certified, the ENERGY STAR label will be located next to the NFRC label

Publication Date

Thu, 05/18/2023 - 12:00

The 2-foot overhang on the left performs better than the 2-foot vertical fin on the right for providing shade in the summer and solar heat gain in the winter (results shown for west-facing window, 2pm, 36N latitude).

Publication Date

Tue, 07/25/2023 - 12:00

The 8-foot-deep west-facing overhang on the left provides much better shading late in the day than the 2-foot-deep overhang on the right (results shown for west-facing window, late summer, 36N latitude).

Publication Date

Tue, 07/25/2023 - 12:00

Right - In cooler climates, landscape shading should focus on the east- and west-facing walls, while leaving the south side of the house clear for solar access in winter (well-sized roof overhangs could provide summer shading for the south-facing windows)

Publication Date

Fri, 09/24/2021 - 12:00

The 8-foot deck/overhang on the left provides better summer shading than the 2-foot extended-width overhang, which performs better than the 2-foot window-width overhang, which performs better than the 2-foot vertical fin (late summer, 36N latitude)

Publication Date

Tue, 07/25/2023 - 12:00

Sheer shades can provide very effective daylighting and glare control while maintaining a softened view to the outside

Publication Date

Tue, 11/03/2015 - 12:00

Karuna Passive House Exterior Shading System Pt 1

Publication Date

May, 2013

Video describing the exterior shading system in a passive house. This video is part of a two-video series by Hammer and Hand.

Karuna Passive House Exterior Shading System Pt 2

Publication Date

May, 2013

Video describing the exterior shading system in a passive house. This video is part of a two-video series by Hammer and Hand.

Sun Control and Shading Devices

Author(s)

Prowler Don,

Bourg Joseph

Organization(s)

Whole Building Design Guide

Publication Date

August, 2016

Article providing fundamental information and recommendations for shading windows for energy savings.

ASES March Webinar: Uncoupling Solar Light and Heat in Passive Solar Design

Author(s)

American Solar Energy Society

Organization(s)

ASES

Publication Date

March, 2022

Presentation from American Solar Energy Society on using spectrally selective window technology for passive solar design.

Passive and Low-Energy Cooling

Guide describing various ways of implementing passive and low-energy cooling techniques for a house.

Multi-layer honeycomb cellular shades such as these can provide summertime energy savings by blocking and reflecting solar heat, as well as wintertime energy savings by providing added insulation.

Publication Date

Thu, 10/01/2015 - 12:00

Adding Automated Shading to the High Performance Toolkit: HVAC, Health & Wellness, and High Tech

Author(s)

Katie Cort,

Shannon Christie

Organization(s)

PNNL,

Attachments Energy Rating Council,

EEBA

Webinar from Katie Cort and Shannon Christie on automated window shading and its applications for energy efficiency and demand response, leading to a discussion on integration for complete smart homes. Free EEBA login required.

Impacts of Shading and Glazing Combinations on Residential Energy Use in a Hot Dry Climate

Author(s)

Farrar-Nagy Sara,

Anderson Ren,

Hancock C E,

Reeves Paul

Organization(s)

National Renewable Energy Laboratory,

NREL,

Partnership for Resource Conservation,

U.S. Department of Energy,

DOE

Publication Date

July, 2000

Study evaluating opportunities for reducing cooling energy use in a hot dry climate through the use of shading and window options.

Permanent awnings help minimize unwanted solar heat gain from high overhead summer sun.

Thermal mass stained concrete slab absorb solar heat during the day and release it into the rooms at night.

Passive Solar Design Principles

Publication Date

October, 2013

Author(s)

Master Builders Victoria

Organization(s)

Master Builders Victoria

Video from Master Builders Victoria on passive solar design principles for home construction.

Right – Horizontal overhangs on this house block sunlight in the summer while allowing it in during winter

Infrared photometry shows the impact of a roof overhang on the south façade of a home, where the unshaded patio stonework is significantly hotter than the shaded portions of the patio and wall surfaces (temperature scale shown is in Celsius).

Exterior shading devices such as awnings or overhangs can significantly reduce cooling loads

Publication Date

Sun, 10/14/2007 - 12:00

Right – This model home for the Solar Decathlon competition incorporates vertical trellises and retractable exterior blinds to control solar heat gain.

These folding louvered porch doors provide effective shade from low-angle east and west sunlight and can open for views; the photovoltaic panels overhead allow in filtered natural light

Solar Radiation Data Manual for Buildings

Author(s)

Marion William,

Wilcox Stephen

Organization(s)

National Renewable Energy Laboratory,

NREL

Document providing incident solar radiation data and window overhang sizing guidance for multiple locations across the U.S.

DOE ZERH HIA 2014 Case Study: Imery Group Proud Green Home, Serenbe, GA

Author(s)

Pacific Northwest National Laboratory,

U.S. Department of Energy

Organization(s)

PNNL,

DOE

Publication Date

April, 2014

Case study describing the first DOE Zero Energy Ready Home in Georgia that achieved a HERS score of 40 without PV and -10 with PV.

DOE ZERH HIA 2014 Case Study: One Sky Homes, Cottle Zero Net Energy Home, San Jose, CA

Author(s)

Pacific Northwest National Laboratory,

U.S. Department of Energy

Organization(s)

PNNL,

DOE

Publication Date

September, 2014

Case study describing a DOE Zero Energy Ready Home 2014 Housing Innovation Award winner that scored HERS 69 without PV and -1 with PV.