Retractable roof
Encyclopedia
A retractable roof is a kinetic architectural
element used in many sports venues, in which a roof made of a suitable material can readily be mechanically deployed from some retracted or open position into a closed or extended position that completely covers the field of play and spectator areas. They are generally used in locales where inclement weather, extreme heat, or extreme cold are prevalent during the respective sports seasons, in order to allow for playing of traditionally outdoor sports in more favorable conditions, as well as the comfort of spectators watching games played in such weather. Unlike their predecessors, the domes built primarily during the 1960s, 1970s, and early 1980s, retractable roofs also allow for playing of the same traditionally outdoor sports in outdoor conditions when the weather is more favorable.
Another purpose of retractable roofs is to allow for growth of natural grass playing fields in environments where extreme hot and/or cold temperatures would otherwise make installation and maintenance of such a field cost prohibitive. Not limited to stadiums, retractable roofs are also used in residences, commercial buildings, swim centers, and other places with overhead enclosures. Installations throughout the world employ a variety of different configurations and styles.
, United States
. Constructed in 1961 for the Pittsburgh Civic Light Opera
, the arena was home to minor-league and NCAA D-1 basketball and ice hockey teams before becoming the home of the NHL's
Pittsburgh Penguins
in 1967, as well as hosting over a dozen regular season NBA
games in the 1960's and 1970's. The arena's dome-shaped roof covers 170000 square feet (15,793.5 m²) and is made up of 8 equal segments constructed from close to 3,000 tons of steel, in which six segments can retract underneath the remaining two, supported by an 260 feet (79.2 m) long exterior cantilevered arm. http://www.mellonarena.com/site41.php
Olympic Stadium
in Montreal
, Quebec
was slated to be the first outdoor retractable roof stadium at its debut for the 1976 Summer Olympic Games. However, plagued by construction problems, the roof was not installed until 1987, and was not retractable until 1988. Even then, movement of the roof was impossible in high wind conditions, and technical problems plagued the facility. A permanent, fixed roof was installed in 1998. By contrast, the Rogers Centre
(formerly known as SkyDome) in Toronto
, Ontario
had a fully functional retractable roof at its debut in .
style roof, while Toyota Stadium
in Japan
has an accordion
-like roof. Most retractable roofs are made of metal, while some, such as the roof of University of Phoenix Stadium
, are made of water-resistant fabric. Although each retractable roof differs in these aspects, Safeco Field's
roof is unique in that it is the only one in North America that does not form a climate-controlled enclosure when in the extended position; rather, it acts as an "umbrella" to cover the playing field and spectator areas during inclement weather, with no side walls enclosing the stadium.
and MLB
, as well as from stadium to stadium. In general, if a game begins with the roof open and weather conditions become less favorable, the home team may, with the approval of the field officials and visiting team, request the roof be closed. Depending on the stadium, weather or gameplay conditions, and the judgment of the officials, play may or may not continue until the roof is fully closed. If the game begins with the roof closed, it may be opened under some circumstances depending on the venue. If it is closed after the game begins, typically it must remain closed for the duration of the game.
or tempered glass roofs for safer sports play and durability.
Hinged at the structure’s gutters, open roofs fully close and open by the mechanics of a rack and pinion system or a push/pull drive system. Comparable to the benefits of retractable roofs, open roof systems offer players year long usage, protection from inclement weather when needed, and the feeling of an outdoor environment.
Open roofs are typically seen at smaller athletic venues such as country clubs and universities. Both retractable roof and open roof systems are also used in the construction of commercial greenhouses and garden centers for climate control purposes.
Kinetic Architecture
Kinetic architecture is a concept where buildings are designed so that significant portions can move while retaining structural integrity.A building's capability for motion can be used just to enhance it aesthetic qualities - but can also allow it to respond to environmental conditions and to...
element used in many sports venues, in which a roof made of a suitable material can readily be mechanically deployed from some retracted or open position into a closed or extended position that completely covers the field of play and spectator areas. They are generally used in locales where inclement weather, extreme heat, or extreme cold are prevalent during the respective sports seasons, in order to allow for playing of traditionally outdoor sports in more favorable conditions, as well as the comfort of spectators watching games played in such weather. Unlike their predecessors, the domes built primarily during the 1960s, 1970s, and early 1980s, retractable roofs also allow for playing of the same traditionally outdoor sports in outdoor conditions when the weather is more favorable.
Another purpose of retractable roofs is to allow for growth of natural grass playing fields in environments where extreme hot and/or cold temperatures would otherwise make installation and maintenance of such a field cost prohibitive. Not limited to stadiums, retractable roofs are also used in residences, commercial buildings, swim centers, and other places with overhead enclosures. Installations throughout the world employ a variety of different configurations and styles.
History
The first retractable roof sports venue was Civic Arena in Pittsburgh, PennsylvaniaPennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Constructed in 1961 for the Pittsburgh Civic Light Opera
Pittsburgh Civic Light Opera
Pittsburgh Civic Light Opera is a nonprofit professional theater company based in the Cultural District of Downtown Pittsburgh, Pennsylvania, USA....
, the arena was home to minor-league and NCAA D-1 basketball and ice hockey teams before becoming the home of the NHL's
National Hockey League
The National Hockey League is an unincorporated not-for-profit association which operates a major professional ice hockey league of 30 franchised member clubs, of which 7 are currently located in Canada and 23 in the United States...
Pittsburgh Penguins
Pittsburgh Penguins
The Pittsburgh Penguins are a professional ice hockey team based in Pittsburgh, Pennsylvania. They are members of the Atlantic Division of the Eastern Conference of the National Hockey League . The franchise was founded in 1967 as one of the first expansion teams during the league's original...
in 1967, as well as hosting over a dozen regular season NBA
National Basketball Association
The National Basketball Association is the pre-eminent men's professional basketball league in North America. It consists of thirty franchised member clubs, of which twenty-nine are located in the United States and one in Canada...
games in the 1960's and 1970's. The arena's dome-shaped roof covers 170000 square feet (15,793.5 m²) and is made up of 8 equal segments constructed from close to 3,000 tons of steel, in which six segments can retract underneath the remaining two, supported by an 260 feet (79.2 m) long exterior cantilevered arm. http://www.mellonarena.com/site41.php
Olympic Stadium
Olympic Stadium (Montreal)
The Olympic Stadium is a multi-purpose stadium in the Hochelaga-Maisonneuve district of Montreal, Quebec, Canada built as the main venue for the 1976 Summer Olympics...
in Montreal
Montreal
Montreal is a city in Canada. It is the largest city in the province of Quebec, the second-largest city in Canada and the seventh largest in North America...
, Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
was slated to be the first outdoor retractable roof stadium at its debut for the 1976 Summer Olympic Games. However, plagued by construction problems, the roof was not installed until 1987, and was not retractable until 1988. Even then, movement of the roof was impossible in high wind conditions, and technical problems plagued the facility. A permanent, fixed roof was installed in 1998. By contrast, the Rogers Centre
Rogers Centre
Rogers Centre is a multi-purpose stadium, in Downtown Toronto, Ontario, Canada, situated next to the CN Tower, near the shores of Lake Ontario. Opened in 1989, it is home to the Toronto Blue Jays of Major League Baseball and the Toronto Argonauts of the Canadian Football League...
(formerly known as SkyDome) in Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
, Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
had a fully functional retractable roof at its debut in .
Types of retractable roofs
Architecturally speaking, retractable roofs vary greatly from stadium to stadium in shape, material and movement. For example, Miller Park has a fanFan (implement)
A hand-held fan is an implement used to induce an airflow for the purpose of cooling or refreshing oneself. Any broad, flat surface waved back-and-forth will create a small airflow and therefore can be considered a rudimentary fan...
style roof, while Toyota Stadium
Toyota Stadium
is a 45,000 seat retractable roof stadium in Toyota, Aichi Prefecture, Japan. It was built in 2001 and is often used as home to the J. League club Nagoya Grampus...
in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
has an accordion
Accordion
The accordion is a box-shaped musical instrument of the bellows-driven free-reed aerophone family, sometimes referred to as a squeezebox. A person who plays the accordion is called an accordionist....
-like roof. Most retractable roofs are made of metal, while some, such as the roof of University of Phoenix Stadium
University of Phoenix Stadium
University of Phoenix Stadium, opened August 1, 2006, is a multipurpose football stadium located in Glendale, Arizona. It is the home of the Arizona Cardinals of the National Football League and the annual Fiesta Bowl...
, are made of water-resistant fabric. Although each retractable roof differs in these aspects, Safeco Field's
Safeco Field
Safeco Field is a retractable roof baseball stadium located in Seattle, Washington. The stadium, owned and operated by the Washington-King County Stadium Authority, is the home stadium of the Seattle Mariners of Major League Baseball and has a seating capacity of 47,878 for baseball...
roof is unique in that it is the only one in North America that does not form a climate-controlled enclosure when in the extended position; rather, it acts as an "umbrella" to cover the playing field and spectator areas during inclement weather, with no side walls enclosing the stadium.
Gameplay with retractable roofs
In North American major sports leagues, specific rules exist governing the movement of retractable roofs before and during gameplay. These rules vary between the NFLNational Football League
The National Football League is the highest level of professional American football in the United States, and is considered the top professional American football league in the world. It was formed by eleven teams in 1920 as the American Professional Football Association, with the league changing...
and MLB
Major League Baseball
Major League Baseball is the highest level of professional baseball in the United States and Canada, consisting of teams that play in the National League and the American League...
, as well as from stadium to stadium. In general, if a game begins with the roof open and weather conditions become less favorable, the home team may, with the approval of the field officials and visiting team, request the roof be closed. Depending on the stadium, weather or gameplay conditions, and the judgment of the officials, play may or may not continue until the roof is fully closed. If the game begins with the roof closed, it may be opened under some circumstances depending on the venue. If it is closed after the game begins, typically it must remain closed for the duration of the game.
Alternatives to retractable roofs
Some modern athletic facilities are using affordable, less complex roof systems that resemble retractable roofs in appearance and effect. These roof systems, commonly referred to as open roofs, are constructed with similar materials as retractable roofs. Most open roof companies offer polycarbonatePolycarbonate
PolycarbonatePhysical PropertiesDensity 1.20–1.22 g/cm3Abbe number 34.0Refractive index 1.584–1.586FlammabilityV0-V2Limiting oxygen index25–27%Water absorption – Equilibrium0.16–0.35%Water absorption – over 24 hours0.1%...
or tempered glass roofs for safer sports play and durability.
Hinged at the structure’s gutters, open roofs fully close and open by the mechanics of a rack and pinion system or a push/pull drive system. Comparable to the benefits of retractable roofs, open roof systems offer players year long usage, protection from inclement weather when needed, and the feeling of an outdoor environment.
Open roofs are typically seen at smaller athletic venues such as country clubs and universities. Both retractable roof and open roof systems are also used in the construction of commercial greenhouses and garden centers for climate control purposes.
External links
- CBC archives The architect explains the roof system for SkyDome (now Rogers CentreRogers CentreRogers Centre is a multi-purpose stadium, in Downtown Toronto, Ontario, Canada, situated next to the CN Tower, near the shores of Lake Ontario. Opened in 1989, it is home to the Toronto Blue Jays of Major League Baseball and the Toronto Argonauts of the Canadian Football League...
) in TorontoTorontoToronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
. - CBC Archives A clip from 1975 where the stadium architect talks about his design for the Montreal Olympic Stadium.
- CBC Archives A look back on the history of the Montreal Olympic Stadium (1999).
- Guidelines for movement of a retractable roof (Major League BaseballMajor League BaseballMajor League Baseball is the highest level of professional baseball in the United States and Canada, consisting of teams that play in the National League and the American League...
) - roof projects