Solar Reflectance Index in the built environment - Revision history

Editor at 10:31, 30 July 2021

2021-07-30T10:31:20Z

← Older revision		Revision as of 10:31, 30 July 2021
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	* Albedo.		* Albedo.
		+	* Amber warnings raise building overheating concern.
	* Cool roofs.		* Cool roofs.
	* Emissivity.		* Emissivity.

Editor at 17:11, 15 September 2020

2020-09-15T17:11:58Z

← Older revision		Revision as of 17:11, 15 September 2020
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	* Thermal mass		* Thermal mass
	* Thermal optical properties.		* Thermal optical properties.
		+	* Types of cool roofs.
	* Urban heat island effect.		* Urban heat island effect.

Designing Buildings at 09:53, 14 September 2020

2020-09-14T09:53:50Z

← Older revision		Revision as of 09:53, 14 September 2020
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	* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].		* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].

−	[[Category:~~Standards_/_measurements~~]] [[Category:DCN_Standard]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Standard]] [[Category:Standards_/_measurements]]

116.87.137.129 at 04:15, 14 May 2020

2020-05-14T04:15:28Z

← Older revision		Revision as of 04:15, 14 May 2020
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−	The ~~[https://www.otm.sg/solar-reflectance-index-sri~~ Solar Reflectance Index (SRI)] is a measure of the solar reflectance and emissivity of materials that can be used as an indicator of how hot they are likely to become when solar radiation is incident on their surface. The lower the SRI, the hotter a material is likely to become in the sunshine.	+	The Solar Reflectance Index (SRI) is a measure of the solar reflectance and emissivity of materials that can be used as an indicator of how hot they are likely to become when solar radiation is incident on their surface. The lower the SRI, the hotter a material is likely to become in the sunshine.

	This is important as solar radiation can cause buildings to overheat if their external fabric has a high solar absorptance and is unable to 'lose' (emit) absorbed heat by re-radiating it to the outside. In addition, the high solar absorbent nature of many human-made surfaces means that urban areas can have a higher average temperature than surrounding green spaces. This is referred to as the urban heat island effect.		This is important as solar radiation can cause buildings to overheat if their external fabric has a high solar absorptance and is unable to 'lose' (emit) absorbed heat by re-radiating it to the outside. In addition, the high solar absorbent nature of many human-made surfaces means that urban areas can have a higher average temperature than surrounding green spaces. This is referred to as the urban heat island effect.
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	* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].		* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].

−	[[Category:Standards_/_measurements]]	+	[[Category:Standards_/_measurements]] [[Category:DCN_Standard]]

116.87.137.129 at 03:42, 14 May 2020

2020-05-14T03:42:15Z

← Older revision		Revision as of 03:42, 14 May 2020
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−	The Solar Reflectance Index (SRI) is a measure of the solar reflectance and emissivity of materials that can be used as an indicator of how hot they are likely to become when solar radiation is incident on their surface. The lower the SRI, the hotter a material is likely to become in the sunshine.	+	The [https://www.otm.sg/solar-reflectance-index-sri Solar Reflectance Index (SRI)] is a measure of the solar reflectance and emissivity of materials that can be used as an indicator of how hot they are likely to become when solar radiation is incident on their surface. The lower the SRI, the hotter a material is likely to become in the sunshine.

	This is important as solar radiation can cause buildings to overheat if their external fabric has a high solar absorptance and is unable to 'lose' (emit) absorbed heat by re-radiating it to the outside. In addition, the high solar absorbent nature of many human-made surfaces means that urban areas can have a higher average temperature than surrounding green spaces. This is referred to as the urban heat island effect.		This is important as solar radiation can cause buildings to overheat if their external fabric has a high solar absorptance and is unable to 'lose' (emit) absorbed heat by re-radiating it to the outside. In addition, the high solar absorbent nature of many human-made surfaces means that urban areas can have a higher average temperature than surrounding green spaces. This is referred to as the urban heat island effect.

Designing Buildings at 11:45, 28 March 2019

2019-03-28T11:45:28Z

← Older revision		Revision as of 11:45, 28 March 2019
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	= External references =		= External references =

−	* Autodesk, ~~[http://sustainabilityworkshop.autodesk.com/buildings/direct-solar-gain~~ Direct solar gain].	+	* Autodesk, Direct solar gain.
	* The US department of energy, Cool roofs.		* The US department of energy, Cool roofs.
	* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].		* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].

	[[Category:Standards_/_measurements]]		[[Category:Standards_/_measurements]]

Designing Buildings at 14:30, 20 March 2019

2019-03-20T14:30:19Z

← Older revision		Revision as of 14:30, 20 March 2019
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	SRI is a scale from 0 to 100 on which materials that absorb and retain solar radiation (and so become hotter in sunshine) have a lower number, whilst highly reflective materials (which remain cooler in sunshine) have a higher number.		SRI is a scale from 0 to 100 on which materials that absorb and retain solar radiation (and so become hotter in sunshine) have a lower number, whilst highly reflective materials (which remain cooler in sunshine) have a higher number.

−	The ~~[http://energy.lbl.gov/coolroof/ref_01.htm~~ US department of energy] defines the Solar Reflectance Index (SRI.) as '…a measure of the roof's ability to reject solar heat, as shown by a small temperature rise. It is defined so that a standard black (reflectance 0.05, emittance 0.90) is 0 and a standard white (reflectance 0.80, emittance 0.90) is 100. For example, the standard black has a temperature rise of 90 deg. F (50 deg. C) in full sun, and the standard white has a temperature rise of 14.6 deg. F (8.1 deg. C). Once the maximum temperature rise of a given material has been computed, the SRI can be computed by interpolating between the values for white and black.'	+	The US department of energy defines the Solar Reflectance Index (SRI.) as '…a measure of the roof's ability to reject solar heat, as shown by a small temperature rise. It is defined so that a standard black (reflectance 0.05, emittance 0.90) is 0 and a standard white (reflectance 0.80, emittance 0.90) is 100. For example, the standard black has a temperature rise of 90 deg. F (50 deg. C) in full sun, and the standard white has a temperature rise of 14.6 deg. F (8.1 deg. C). Once the maximum temperature rise of a given material has been computed, the SRI can be computed by interpolating between the values for white and black.'

	NB This definition means that it is possible to have materials with an SRI of less than 0 or more than 100.		NB This definition means that it is possible to have materials with an SRI of less than 0 or more than 100.

Designing Buildings at 10:59, 21 December 2018

2018-12-21T10:59:35Z

← Older revision		Revision as of 10:59, 21 December 2018
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	Source: Cambridge Science Park		Source: Cambridge Science Park

−	~~= Find out more =~~	+	= Related articles on Designing Buildings Wiki =
−		+
−	=== Related articles on Designing Buildings Wiki ===	+

	* Albedo.		* Albedo.
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	* Urban heat island effect.		* Urban heat island effect.

−	=== External references ===	+	= External references =

	* Autodesk, [http://sustainabilityworkshop.autodesk.com/buildings/direct-solar-gain Direct solar gain].		* Autodesk, [http://sustainabilityworkshop.autodesk.com/buildings/direct-solar-gain Direct solar gain].
−	* The US department of energy, ~~[http://energy.lbl.gov/coolroof/ref_01.htm~~ Cool roofs].	+	* The US department of energy, Cool roofs.
	* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].		* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].

	[[Category:Standards_/_measurements]]		[[Category:Standards_/_measurements]]

Editor: Reverted edits by 129.12.103.53 (talk) to last revision by Editor

2018-02-22T13:46:41Z

Reverted edits by 129.12.103.53 (talk) to last revision by Editor

← Older revision		Revision as of 13:46, 22 February 2018
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	The selection of materials with a high SRI can reduce indirect solar gain in buildings and reduce the urban heat island effect. For example, metal roofs finished with a high SRI coating will have a lower temperature under sunny conditions compared to a similar, uncoated metal roof. However, effective solar design is more complicated than simply selecting high SRI materials, as in cooler locations solar gain may actually be desirable.		The selection of materials with a high SRI can reduce indirect solar gain in buildings and reduce the urban heat island effect. For example, metal roofs finished with a high SRI coating will have a lower temperature under sunny conditions compared to a similar, uncoated metal roof. However, effective solar design is more complicated than simply selecting high SRI materials, as in cooler locations solar gain may actually be desirable.
−
−	~~cock~~

	SRI can be considered a better indicator of a materials response to solar radiation than 'albedo' (from the Latin for 'whiteness') as albedo is a simple ratio of reflected to incident radiation and does not take account of emissivity.		SRI can be considered a better indicator of a materials response to solar radiation than 'albedo' (from the Latin for 'whiteness') as albedo is a simple ratio of reflected to incident radiation and does not take account of emissivity.
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	* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].		* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].

−	~~[[Category:Articles_needing_more_work]]~~ [[Category:Standards_/_measurements]]	+	[[Category:Standards_/_measurements]]

129.12.103.53 at 12:42, 22 February 2018

2018-02-22T12:42:55Z

← Older revision		Revision as of 12:42, 22 February 2018
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	The selection of materials with a high SRI can reduce indirect solar gain in buildings and reduce the urban heat island effect. For example, metal roofs finished with a high SRI coating will have a lower temperature under sunny conditions compared to a similar, uncoated metal roof. However, effective solar design is more complicated than simply selecting high SRI materials, as in cooler locations solar gain may actually be desirable.		The selection of materials with a high SRI can reduce indirect solar gain in buildings and reduce the urban heat island effect. For example, metal roofs finished with a high SRI coating will have a lower temperature under sunny conditions compared to a similar, uncoated metal roof. However, effective solar design is more complicated than simply selecting high SRI materials, as in cooler locations solar gain may actually be desirable.
		+
		+	cock

	SRI can be considered a better indicator of a materials response to solar radiation than 'albedo' (from the Latin for 'whiteness') as albedo is a simple ratio of reflected to incident radiation and does not take account of emissivity.		SRI can be considered a better indicator of a materials response to solar radiation than 'albedo' (from the Latin for 'whiteness') as albedo is a simple ratio of reflected to incident radiation and does not take account of emissivity.
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	* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].		* Cool Roof Rating Council [http://www.energy.ca.gov/title24/2008standards/sri_calculator/SRI_Calculator_Worksheet.pdf Solar reflectance index calculation worksheet].

−	[[Category:Standards_/_measurements]]	+	[[Category:Articles_needing_more_work]] [[Category:Standards_/_measurements]]