Transparent insulation - Revision history

Designing Buildings at 06:53, 17 October 2022

2022-10-17T06:53:11Z

← Older revision		Revision as of 06:53, 17 October 2022
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	This article is based on a paper written by Mark Dowson of --[[User:Buro_Happold\|Buro Happold]]. An online version of Mark's EngD thesis can be downloaded at the Brunel University website: [http://bura.brunel.ac.uk/bitstream/2438/7075/3/FulltextThesis.pdf http://bura.brunel.ac.uk/bitstream/2438/7075/3/FulltextThesis.pdf]		This article is based on a paper written by Mark Dowson of --[[User:Buro_Happold\|Buro Happold]]. An online version of Mark's EngD thesis can be downloaded at the Brunel University website: [http://bura.brunel.ac.uk/bitstream/2438/7075/3/FulltextThesis.pdf http://bura.brunel.ac.uk/bitstream/2438/7075/3/FulltextThesis.pdf]

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

	* Advanced phase change materials.		* Advanced phase change materials.

Designing Buildings: Reverted edits by 104.225.189.77 (talk) to last revision by Designing Buildings

2020-12-12T09:05:53Z

Reverted edits by 104.225.189.77 (talk) to last revision by Designing Buildings

← Older revision		Revision as of 09:05, 12 December 2020
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−	= ~~lol~~ =	+	= Introduction =

		+	Honeycomb transparent insulation was first developed in the 1960s to enhance the insulation value of glazing systems with minimal loss to light transmission (Hollands 1965). Over the past 25 years, transparent insulation materials (TIMs) have been applied to windows, walls, skylights, roofs and high-performance solar collectors (Dolley et al. 1994, Kaushika and Sumathy 2003).
		+
		+	Transparent insulation materials perform a similar function to opaque insulation, but they have the ability to transmit daylight and solar energy, reducing the need for artificial light and heating. They transmit heat, mainly through conduction and radiation, but convection is usually suppressed (Kaushika and Sumathy 2003).
		+
		+	[[File:Transparent_insulation_materials.jpg\|link=File:Transparent_insulation_materials.jpg]]
		+
		+	The thermal and optical properties of transparent insulation materials depend on the material, its structure, thickness, quality and uniformity. They typically consist of either glass or plastic arranged in a honeycomb, capillary or closed cell construction. Alternatively, granular or monolithic silica aerogel can be used to achieve higher insulation values.
		+
		+	Depending on the structure of the material, its arrangement can be classified as:
		+
		+	* Absorber perpendicular.
		+	* Absorber parallel.
	* Cavity.		* Cavity.
	* Quasi-homogeneous.		* Quasi-homogeneous.
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	* U Value.		* U Value.

−	~~[[Category:Articles_needing_more_work]] [[Category:Conservation]]~~ [[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge~~]] [[Category:Definitions]] [[Category:Education~~]] [[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]

104.225.189.77 at 21:20, 11 December 2020

2020-12-11T21:20:44Z

← Older revision		Revision as of 21:20, 11 December 2020
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−	= ~~Introduction~~ =	+	= lol =

−	Honeycomb transparent insulation was first developed in the 1960s to enhance the insulation value of glazing systems with minimal loss to light transmission (Hollands 1965). Over the past 25 years, transparent insulation materials (TIMs) have been applied to windows, walls, skylights, roofs and high-performance solar collectors (Dolley et al. 1994, Kaushika and Sumathy 2003).
−
−	Transparent insulation materials perform a similar function to opaque insulation, but they have the ability to transmit daylight and solar energy, reducing the need for artificial light and heating. They transmit heat, mainly through conduction and radiation, but convection is usually suppressed (Kaushika and Sumathy 2003).
−
−	~~[[File:Transparent_insulation_materials.jpg\|link=File:Transparent_insulation_materials.jpg]]~~
−
−	The thermal and optical properties of transparent insulation materials depend on the material, its structure, thickness, quality and uniformity. They typically consist of either glass or plastic arranged in a honeycomb, capillary or closed cell construction. Alternatively, granular or monolithic silica aerogel can be used to achieve higher insulation values.
−
−	~~Depending on the structure of the material, its arrangement can be classified as:~~
−
−	* Absorber perpendicular.
−	* Absorber parallel.
	* Cavity.		* Cavity.
	* Quasi-homogeneous.		* Quasi-homogeneous.
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	* U Value.		* U Value.

−	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]	+	[[Category:Articles_needing_more_work]] [[Category:Conservation]] [[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Definitions]] [[Category:Education]] [[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]

Designing Buildings at 11:25, 14 September 2020

2020-09-14T11:25:48Z

← Older revision		Revision as of 11:25, 14 September 2020
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	* U Value.		* U Value.

−	[[Category:~~Sustainability~~]] [[Category:~~Construction_techniques~~]] [[Category:~~Products_/_components~~]] [[Category:~~DCN_Product_Knowledge~~]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]

Editor: Reverted edits by 149.136.33.252 (talk) to last revision by Editor

2019-09-12T17:49:57Z

Reverted edits by 149.136.33.252 (talk) to last revision by Editor

← Older revision		Revision as of 17:49, 12 September 2019
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	= Introduction =		= Introduction =

−	Honeycomb transparent insulation was first developed in the 1960s to enhance the insulation value of glazing systems with minimal loss to light transmission (Hollands 1965). Over the past 25 years, transparent insulation materials (TIMs) have been applied to windows, walls, skylights, roofs and high-performance solar collectors (Dolley et al. 1994~~, Ramadan 1998~~, Kaushika and Sumathy 2003).	+	Honeycomb transparent insulation was first developed in the 1960s to enhance the insulation value of glazing systems with minimal loss to light transmission (Hollands 1965). Over the past 25 years, transparent insulation materials (TIMs) have been applied to windows, walls, skylights, roofs and high-performance solar collectors (Dolley et al. 1994, Kaushika and Sumathy 2003).

	Transparent insulation materials perform a similar function to opaque insulation, but they have the ability to transmit daylight and solar energy, reducing the need for artificial light and heating. They transmit heat, mainly through conduction and radiation, but convection is usually suppressed (Kaushika and Sumathy 2003).		Transparent insulation materials perform a similar function to opaque insulation, but they have the ability to transmit daylight and solar energy, reducing the need for artificial light and heating. They transmit heat, mainly through conduction and radiation, but convection is usually suppressed (Kaushika and Sumathy 2003).
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	* U Value.		* U Value.

−	[[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]	+	[[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]] [[Category:DCN_Product_Knowledge]]

149.136.33.252 at 16:39, 12 September 2019

2019-09-12T16:39:22Z

← Older revision		Revision as of 16:39, 12 September 2019
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	= Introduction =		= Introduction =

−	Honeycomb transparent insulation was first developed in the 1960s to enhance the insulation value of glazing systems with minimal loss to light transmission (Hollands 1965). Over the past 25 years, transparent insulation materials (TIMs) have been applied to windows, walls, skylights, roofs and high-performance solar collectors (Dolley et al. 1994, Kaushika and Sumathy 2003).	+	Honeycomb transparent insulation was first developed in the 1960s to enhance the insulation value of glazing systems with minimal loss to light transmission (Hollands 1965). Over the past 25 years, transparent insulation materials (TIMs) have been applied to windows, walls, skylights, roofs and high-performance solar collectors (Dolley et al. 1994, Ramadan 1998, Kaushika and Sumathy 2003).

	Transparent insulation materials perform a similar function to opaque insulation, but they have the ability to transmit daylight and solar energy, reducing the need for artificial light and heating. They transmit heat, mainly through conduction and radiation, but convection is usually suppressed (Kaushika and Sumathy 2003).		Transparent insulation materials perform a similar function to opaque insulation, but they have the ability to transmit daylight and solar energy, reducing the need for artificial light and heating. They transmit heat, mainly through conduction and radiation, but convection is usually suppressed (Kaushika and Sumathy 2003).

Editor at 14:12, 17 May 2018

2018-05-17T14:12:31Z

← Older revision		Revision as of 14:12, 17 May 2018
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	* Floor insulation.		* Floor insulation.
	* Insulation specification.		* Insulation specification.
		+	* Plastic.
	* Polycarbonate plastic.		* Polycarbonate plastic.
	* The thermal behaviour of spaces enclosed by fabric membranes.		* The thermal behaviour of spaces enclosed by fabric membranes.

Designing Buildings at 13:53, 4 May 2018

2018-05-04T13:53:21Z

← Older revision		Revision as of 13:53, 4 May 2018
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	* Advanced phase change materials.		* Advanced phase change materials.
	* Aerogel.		* Aerogel.
		+	* BREEAM Insulation.
	* ETFE		* ETFE
	* Floor insulation.		* Floor insulation.

Editor at 15:11, 23 January 2018

2018-01-23T15:11:16Z

← Older revision		Revision as of 15:11, 23 January 2018
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	* Polycarbonate plastic.		* Polycarbonate plastic.
	* The thermal behaviour of spaces enclosed by fabric membranes.		* The thermal behaviour of spaces enclosed by fabric membranes.
		+	* Types of insulation.
	* U Value.		* U Value.

	[[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]		[[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]

Editor at 13:23, 30 May 2017

2017-05-30T13:23:39Z

← Older revision		Revision as of 13:23, 30 May 2017
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	= Introduction =		= Introduction =

−	Honeycomb transparent insulation was first developed in the 1960s to enhance the insulation value of glazing systems with minimal loss to light transmission (Hollands 1965). Over the past 25 years, transparent insulation materials (TIMs) have been applied to windows, walls, skylights, roofs and high-performance solar collectors (Dolley et al. 1994, Kaushika and Sumathy 2003). Transparent insulation materials perform a similar function to opaque insulation, but they have the ability to transmit daylight and solar energy, reducing the need for artificial light and heating. They transmit heat, mainly through conduction and radiation, but convection is usually suppressed (Kaushika and Sumathy 2003).	+	Honeycomb transparent insulation was first developed in the 1960s to enhance the insulation value of glazing systems with minimal loss to light transmission (Hollands 1965). Over the past 25 years, transparent insulation materials (TIMs) have been applied to windows, walls, skylights, roofs and high-performance solar collectors (Dolley et al. 1994, Kaushika and Sumathy 2003).
		+
		+	Transparent insulation materials perform a similar function to opaque insulation, but they have the ability to transmit daylight and solar energy, reducing the need for artificial light and heating. They transmit heat, mainly through conduction and radiation, but convection is usually suppressed (Kaushika and Sumathy 2003).

	[[File:Transparent_insulation_materials.jpg\|link=File:Transparent_insulation_materials.jpg]]		[[File:Transparent_insulation_materials.jpg\|link=File:Transparent_insulation_materials.jpg]]
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	Depending on the structure of the material, its arrangement can be classified as:		Depending on the structure of the material, its arrangement can be classified as:

−	* ~~Aabsorber~~ perpendicular.	+	* Absorber perpendicular.
	* Absorber parallel.		* Absorber parallel.
	* Cavity.		* Cavity.
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	Figure 1: Types of transparent insulation		Figure 1: Types of transparent insulation

−	Figure 2 (below) compares the thermal conductivity of various transparent insulation materials and other insulation products. Okalux Glass Honeycomb is a commercially produced absorber perpendicular TIM with a thermal conductivity of 0.039W/m.K (Platzer et al. 2004). Translucent silica aerogel, a quasi-homogenous TIM, has the lowest thermal conductance of any known solid at 0.004-0.018W/m.K (Yokogawa 2005, Cabot 2009). Only vacuum technology is comparable with thermal conductivities in the region of 0.005W/m.K (Zimmerman et al. 2001).	+	Figure 2 (below) compares the thermal conductivity of various transparent insulation materials and other insulation products. Okalux Glass Honeycomb is a commercially produced absorber perpendicular TIM with a thermal conductivity of 0.039W/m.K (Platzer et al. 2004).
		+
		+	Translucent silica aerogel, a quasi-homogenous TIM, has the lowest thermal conductance of any known solid at 0.004-0.018W/m.K (Yokogawa 2005, Cabot 2009). Only vacuum technology is comparable with thermal conductivities in the region of 0.005W/m.K (Zimmerman et al. 2001).

	[[File:Thermal_conductivities_of_insulation_materials.jpg\|link=File:Thermal_conductivities_of_insulation_materials.jpg]]		[[File:Thermal_conductivities_of_insulation_materials.jpg\|link=File:Thermal_conductivities_of_insulation_materials.jpg]]
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	= Transparent insulation in glazing =		= Transparent insulation in glazing =

−	TIM glazing typically consists of glass or plastic capillaries or honeycomb structures sandwiched between two glass panes. These systems diffuse light well, while reducing glare and shadowing (Lien et al. 1997). Commercial products such as Okalux and Arel glazing can exhibit low U-values with good solar and light transmittance. According to Hutchins and Platzer (1996), 40-mm-thick Okalux capillary glazing, and 50-mm-thick Arel honeycomb glazing can achieve U-values of 1.36 W/m2K, comparable to modern gas filled double glazing. Alternatively, 80 and 100mm thick systems can achieve U-values of 0.8 W/m2 K, respectively, comparable to modern gas filled triple glazing units.	+	TIM glazing typically consists of glass or plastic capillaries or honeycomb structures sandwiched between two glass panes. These systems diffuse light well, while reducing glare and shadowing (Lien et al. 1997). Commercial products such as Okalux and Arel glazing can exhibit low U-values with good solar and light transmittance.
		+
		+	According to Hutchins and Platzer (1996), 40-mm-thick Okalux capillary glazing, and 50-mm-thick Arel honeycomb glazing can achieve U-values of 1.36 W/m2K, comparable to modern gas filled double glazing. Alternatively, 80 and 100mm thick systems can achieve U-values of 0.8 W/m2 K, respectively, comparable to modern gas filled triple glazing units.

	According to Robinson and Hutchins (1994), the application of TIM glazing tends to be limited to skylights, atriums and commercial/industrial facades as the geometric structure of TIMs tends to restrict a clear view to the outside. Transparent insulation materials appear most transparent when viewed front on and tend to be opaque when viewed at an angle. In order to increase the visible transmission of TIM glazing, it is important to increase capillary size, reduce the thickness, or view the transparent insulation material from a distance (Lien et al. 1997).		According to Robinson and Hutchins (1994), the application of TIM glazing tends to be limited to skylights, atriums and commercial/industrial facades as the geometric structure of TIMs tends to restrict a clear view to the outside. Transparent insulation materials appear most transparent when viewed front on and tend to be opaque when viewed at an angle. In order to increase the visible transmission of TIM glazing, it is important to increase capillary size, reduce the thickness, or view the transparent insulation material from a distance (Lien et al. 1997).
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	Kaushika and Sumathy (2003) suggest that considerable progress has been made to reduce the cost of manufacturing transparent insulation. On the basis of this lower cost, Wong et al. (2007), calculated a 3–4-year payback period for an industrial production facility in Salzgitter, Germany, renovated with 7,500m2 of TIM glazing. It is unclear whether these payback periods can be directly translated to the domestic or commercial sector, but nonetheless, this payback period is significantly less than new double glazing.		Kaushika and Sumathy (2003) suggest that considerable progress has been made to reduce the cost of manufacturing transparent insulation. On the basis of this lower cost, Wong et al. (2007), calculated a 3–4-year payback period for an industrial production facility in Salzgitter, Germany, renovated with 7,500m2 of TIM glazing. It is unclear whether these payback periods can be directly translated to the domestic or commercial sector, but nonetheless, this payback period is significantly less than new double glazing.

−	Research into TIM glazing focuses on developing systems using transparent silica aerogel. This lightweight, nanoporous material has an excellent combination of high solar and light transmittance and low thermal conductance (Schultz and Jenson 2008). According to Bahaj et al. (2008), aerogel glazing is often portrayed as the ‘holy grail’ of future windows, offering the potential to achieve U-values as low as 0.1 W/m2 K, as well as high-solar energy and daylight transmittance of approximately 90% (Bahaj et al. 2008, Schultz and Jenson 2008). The thermal, optical and infrared properties of silica aerogels are well known. The material effectively transmits solar light while blocking heat transfer by conduction, convection and thermal infrared radiation. Silica aerogel has the lowest thermal conductivity of any material, ranging from 0.018 W/mK for granular silica aerogel to 0.004 W/mK for evacuated monolithic silica aerogel (Yokogawa 2005, Cabot 2009).	+	Research into TIM glazing focuses on developing systems using transparent silica aerogel. This lightweight, nanoporous material has an excellent combination of high solar and light transmittance and low thermal conductance (Schultz and Jenson 2008).

−	To date, several small-scale prototypes have been constructed to characterise the performance of monolithic silica aerogel in glazing. Samples are sandwiched between glass sheets and evacuated to protect the aerogel from tension and moisture, as most aerogels are brittle and hydrophilic meaning that they will degrade in contact with water (Zhu et al. 2007, Schultz and Jenson 2008). Duer and Svendsen (1998) measured the performance of five different monolithic aerogel slabs, produced in different laboratories, ranging in thickness from 7 to 12 mm. Centre pane U-values of glazed samples ranged from 0.41 to 0.47 W/m2 K. Solar and visual transmittance ranged from 74 to 78% and from 71 to 73%, respectively.	+	According to Bahaj et al. (2008), aerogel glazing is often portrayed as the ‘holy grail’ of future windows, offering the potential to achieve U-values as low as 0.1 W/m2 K, as well as high-solar energy and daylight transmittance of approximately 90% (Bahaj et al. 2008, Schultz and Jenson 2008).
		+
		+	The thermal, optical and infrared properties of silica aerogels are well known. The material effectively transmits solar light while blocking heat transfer by conduction, convection and thermal infrared radiation. Silica aerogel has the lowest thermal conductivity of any material, ranging from 0.018 W/mK for granular silica aerogel to 0.004 W/mK for evacuated monolithic silica aerogel (Yokogawa 2005, Cabot 2009).
		+
		+	To date, several small-scale prototypes have been constructed to characterise the performance of monolithic silica aerogel in glazing. Samples are sandwiched between glass sheets and evacuated to protect the aerogel from tension and moisture, as most aerogels are brittle and hydrophilic meaning that they will degrade in contact with water (Zhu et al. 2007, Schultz and Jenson 2008).
		+
		+	Duer and Svendsen (1998) measured the performance of five different monolithic aerogel slabs, produced in different laboratories, ranging in thickness from 7 to 12 mm. Centre pane U-values of glazed samples ranged from 0.41 to 0.47 W/m2 K. Solar and visual transmittance ranged from 74 to 78% and from 71 to 73%, respectively.

	Jensen et al. (2004), Schultz et al. (2005) and Schultz and Jenson (2008) reported on the performance of monolithic aerogel glazing produced by the Airglass AB plant in Sweden. The largest prototype was a 1.2m2 window, consisting of four 55 cm × 55 cm × 15mm monolithic tiles fitted into an evacuated, sealed framing unit. This prototype achieved a centre pane U-value of 0.66 W/m2K (measured in a laboratory), and an overall U-value of 0.72W/m2K (measured using a hot box), indicating that the effect of thermal bridging at the edges was small. The direct solar transmittance was 75–76% and the normal transmittance in the visible spectrum was 85–90%.		Jensen et al. (2004), Schultz et al. (2005) and Schultz and Jenson (2008) reported on the performance of monolithic aerogel glazing produced by the Airglass AB plant in Sweden. The largest prototype was a 1.2m2 window, consisting of four 55 cm × 55 cm × 15mm monolithic tiles fitted into an evacuated, sealed framing unit. This prototype achieved a centre pane U-value of 0.66 W/m2K (measured in a laboratory), and an overall U-value of 0.72W/m2K (measured using a hot box), indicating that the effect of thermal bridging at the edges was small. The direct solar transmittance was 75–76% and the normal transmittance in the visible spectrum was 85–90%.

−	Despite its impressive combination of thermal and optical properties, monolithic silica aerogel is yet to penetrate the commercial glazing market. According to Rubin and Lampert (1983), the cost, long processing time of aerogel, difficulty in manufacturing uniform samples and lack of adequate protection from tension and moisture are key barriers hindering progress. Duer and Svendsen (1998) and Bahaj et al. (2008) suggest that further work is required to improve the clarity of samples if they are to replace conventional windows. A key issue is that the nanostructure of silica aerogel scatters transmitted light, resulting in a hazy view. Schultz and Jenson (2008) claim that through improved heat treatment techniques, the Airglass AB plant is capable of producing aerogel tiles with parallel and smooth surfaces, resulting in undistorted views when shielded from direct solar radiation. However, when exposed to non-perpendicular solar radiation, visual distortion still occurs. According to Jensen et al. (2004), Schultz et al. (2005) and Schultz and Jenson (2008), aerogel glazing is an excellent option for large areas of north-facing facades, enabling a net energy gain during the heating season. Through developments in edge sealing techniques, units are anticipated to have a lifespan of 20–25 years without degradation (Schultz and Jenson 2008).	+	Despite its impressive combination of thermal and optical properties, monolithic silica aerogel is yet to penetrate the commercial glazing market. According to Rubin and Lampert (1983), the cost, long processing time of aerogel, difficulty in manufacturing uniform samples and lack of adequate protection from tension and moisture are key barriers hindering progress. Duer and Svendsen (1998) and Bahaj et al. (2008) suggest that further work is required to improve the clarity of samples if they are to replace conventional windows.
		+
		+	A key issue is that the nanostructure of silica aerogel scatters transmitted light, resulting in a hazy view. Schultz and Jenson (2008) claim that through improved heat treatment techniques, the Airglass AB plant is capable of producing aerogel tiles with parallel and smooth surfaces, resulting in undistorted views when shielded from direct solar radiation. However, when exposed to non-perpendicular solar radiation, visual distortion still occurs. According to Jensen et al. (2004), Schultz et al. (2005) and Schultz and Jenson (2008), aerogel glazing is an excellent option for large areas of north-facing facades, enabling a net energy gain during the heating season. Through developments in edge sealing techniques, units are anticipated to have a lifespan of 20–25 years without degradation (Schultz and Jenson 2008).

	The use of granular aerogel in glazing offers an alternative solution to monolithic aerogel which is cheaper, more robust and easier to produce on a commercial scale. Systems should not be considered as a direct replacement for transparent windows, because the granules restrict the clear view to the outside. Instead, this material offers the potential to achieve low U-values, enhance light scattering and drastically reduce sound transmission in areas where an outside view is not essential (Wittwer 1992).		The use of granular aerogel in glazing offers an alternative solution to monolithic aerogel which is cheaper, more robust and easier to produce on a commercial scale. Systems should not be considered as a direct replacement for transparent windows, because the granules restrict the clear view to the outside. Instead, this material offers the potential to achieve low U-values, enhance light scattering and drastically reduce sound transmission in areas where an outside view is not essential (Wittwer 1992).
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	The performance of granular aerogel glazing was originally investigated by Wittwer (1992). U-values from 1.1 to 1.3W/m2K were measured for 20-mm-thick glazing units filled with granules ranging from 1 to 9mm in diameter. Smaller granules perform better thermally, as less heat is conducted through air gaps between granules. Optically, the larger aerogel granules permitted more light and solar transmission.		The performance of granular aerogel glazing was originally investigated by Wittwer (1992). U-values from 1.1 to 1.3W/m2K were measured for 20-mm-thick glazing units filled with granules ranging from 1 to 9mm in diameter. Smaller granules perform better thermally, as less heat is conducted through air gaps between granules. Optically, the larger aerogel granules permitted more light and solar transmission.

−	More recently, Reim et al. (2002, 2005) have measured and modelled the performance of granular aerogels encapsulated in a 10mm twin-wall plastic sheet sandwiched between two glass panes with an insulated gas filling. The twin-wall sheet was selected to prevent granules from settling over time, creating a thermal bridge along the top edge. U-values as low as 0.37–0.56W/m2 K were calculated for prototypes containing krypton/argon gas fillings. Without the glass cover panes, the solar and light transmission was 88 and 85%, respectively. Using a thermal model in a German climate, Reim et al. (2002) calculated the energetic benefit of granular aerogel glazing to be comparable to triple glazing. Results demonstrated that granular aerogel glazing could reduce the risk of overheating on southern and east/west facades. On north-facing facades, the energetic balance of aerogel glazing was significantly better than triple glazing due to improved heat retention.	+	More recently, Reim et al. (2002, 2005) have measured and modelled the performance of granular aerogels encapsulated in a 10mm twin-wall plastic sheet sandwiched between two glass panes with an insulated gas filling. The twin-wall sheet was selected to prevent granules from settling over time, creating a thermal bridge along the top edge. U-values as low as 0.37–0.56W/m2 K were calculated for prototypes containing krypton/argon gas fillings. Without the glass cover panes, the solar and light transmission was 88 and 85%, respectively.
		+
		+	Using a thermal model in a German climate, Reim et al. (2002) calculated the energetic benefit of granular aerogel glazing to be comparable to triple glazing. Results demonstrated that granular aerogel glazing could reduce the risk of overheating on southern and east/west facades. On north-facing facades, the energetic balance of aerogel glazing was significantly better than triple glazing due to improved heat retention.

	= Transparent insulation in flat plate solar collectors =		= Transparent insulation in flat plate solar collectors =
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	* Floor insulation.		* Floor insulation.
	* Insulation specification.		* Insulation specification.
		+	* Polycarbonate plastic.
	* The thermal behaviour of spaces enclosed by fabric membranes.		* The thermal behaviour of spaces enclosed by fabric membranes.
	* U Value.		* U Value.

	[[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]		[[Category:Sustainability]] [[Category:Construction_techniques]] [[Category:Products_/_components]]