Designing out fire risk in roof voids - Revision history

Designing Buildings at 05:10, 22 October 2020

2020-10-22T05:10:17Z

← Older revision		Revision as of 05:10, 22 October 2020
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	* [10] The Regulatory Reform (Fire Safety) Order 2005, SI 2005 No. 1541.		* [10] The Regulatory Reform (Fire Safety) Order 2005, SI 2005 No. 1541.

−	[[Category:~~Health_and_safety_/_CDM~~]] [[Category:~~Regulations~~]] [[Category:~~DCN_Regulation~~]] [[Category:~~Standards_/_measurements~~]] [[Category:~~DCN_Standard~~]]	+	[[Category:DCN_Guidance]] [[Category:DCN_Research,_Development_and_Innovation]] [[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]]

Designing Buildings at 13:09, 26 July 2019

2019-07-26T13:09:57Z

← Older revision		Revision as of 13:09, 26 July 2019
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	= About this article =		= About this article =

−	This article was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as 'Fire in the hole. Designing out fire risk in roof voids' in the Spring 2016 edition of [https://ciat.org.uk/at-journal.html AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)	+	This article was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as 'Fire in the hole. Designing out fire risk in roof voids' in the Spring 2016 edition of [https://ciat.org.uk/practice-technical/at-journal.html AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)

	= Related articles on Designing Buildings Wiki =		= Related articles on Designing Buildings Wiki =
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	* [10] The Regulatory Reform (Fire Safety) Order 2005, SI 2005 No. 1541.		* [10] The Regulatory Reform (Fire Safety) Order 2005, SI 2005 No. 1541.

−	[[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]]	+	[[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:DCN_Regulation]] [[Category:Standards_/_measurements]] [[Category:DCN_Standard]]

Editor at 10:32, 30 April 2019

2019-04-30T10:32:05Z

Show changes

Editor at 10:06, 30 April 2019

2019-04-30T10:06:38Z

← Older revision		Revision as of 10:06, 30 April 2019
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−	Fire in concealed spaces such as roof voids can be a killer. This article examines how to reduce the risk at the design stage and during construction. It was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as 'Fire in the hole. Designing out fire risk in roof voids' in the Spring 2016 edition of [https://ciat.org.uk/at-journal.html AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)	+	{\|
		+	\| [[File:Fire.jpg]]
		+	\|-
		+	\| Fire in concealed spaces such as roof voids can be a killer. This article examines how to reduce the risk at the design stage and during construction.
		+	\|}

	= Introduction =		= Introduction =
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	--[[User:CIAT\|CIAT]]		--[[User:CIAT\|CIAT]]
		+
		+	= About this article =
		+
		+	This article was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as 'Fire in the hole. Designing out fire risk in roof voids' in the Spring 2016 edition of [https://ciat.org.uk/at-journal.html AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)

	= Related articles on Designing Buildings Wiki =		= Related articles on Designing Buildings Wiki =

Designing Buildings at 10:54, 21 December 2018

2018-12-21T10:54:59Z

← Older revision		Revision as of 10:54, 21 December 2018
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−	Fire in concealed spaces such as roof voids can be a killer. This article examines how to reduce the risk at the design stage and during construction. It was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as ~~[http://www.ciat.org.uk/en/other/document_summary.cfm/docid/6AAC237A-01F2-491D-AD7F5D02B455E2C1~~ Fire in the hole. Designing out fire risk in roof voids] in the Spring 2016 edition of [https://ciat.org.uk/at-journal.html AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)	+	Fire in concealed spaces such as roof voids can be a killer. This article examines how to reduce the risk at the design stage and during construction. It was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as 'Fire in the hole. Designing out fire risk in roof voids' in the Spring 2016 edition of [https://ciat.org.uk/at-journal.html AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)

	= Introduction =		= Introduction =
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	--[[User:CIAT\|CIAT]]		--[[User:CIAT\|CIAT]]

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

	* Existing guidance on fire compartmentation in roof voids.		* Existing guidance on fire compartmentation in roof voids.
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	* Joint fire code.		* Joint fire code.

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

	* [1] Communities and Local Government (CLG). Compartmentation in roof voids (BD 2846), Queen’s Printer and Controller of Her Majesty’s Stationery Office, 2010.		* [1] Communities and Local Government (CLG). Compartmentation in roof voids (BD 2846), Queen’s Printer and Controller of Her Majesty’s Stationery Office, 2010.

Designing Buildings at 14:13, 7 February 2018

2018-02-07T14:13:49Z

← Older revision		Revision as of 14:13, 7 February 2018
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−	Fire in concealed spaces such as roof voids can be a killer. This article examines how to reduce the risk at the design stage and during construction. It was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as [http://www.ciat.org.uk/en/other/document_summary.cfm/docid/6AAC237A-01F2-491D-AD7F5D02B455E2C1 Fire in the hole. Designing out fire risk in roof voids] in the Spring 2016 edition of [~~http~~://~~www.~~ciat.org.uk~~/en/media_centre~~/at-~~magazine/~~ AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)	+	Fire in concealed spaces such as roof voids can be a killer. This article examines how to reduce the risk at the design stage and during construction. It was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as [http://www.ciat.org.uk/en/other/document_summary.cfm/docid/6AAC237A-01F2-491D-AD7F5D02B455E2C1 Fire in the hole. Designing out fire risk in roof voids] in the Spring 2016 edition of [https://ciat.org.uk/at-journal.html AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)

	= Introduction =		= Introduction =

Designing Buildings at 13:08, 17 May 2016

2016-05-17T13:08:36Z

← Older revision		Revision as of 13:08, 17 May 2016
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	[Fig. 8 Close up of fire damage to pitch roof]		[Fig. 8 Close up of fire damage to pitch roof]

−	= Case study 9: Three-storey timber-frame terraced house =	+	== Case study 9: Three-storey timber-frame terraced house ==

	The fire was started within an upper floor bedroom of a three-storey timber frame terraced house and flames spread into an external wall cavity through failure of a uPVC window frame. From there, it spread into a compartment wall separating dwellings.		The fire was started within an upper floor bedroom of a three-storey timber frame terraced house and flames spread into an external wall cavity through failure of a uPVC window frame. From there, it spread into a compartment wall separating dwellings.

Designing Buildings at 13:22, 27 April 2016

2016-04-27T13:22:34Z

← Older revision		Revision as of 13:22, 27 April 2016
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	BRE Global carries out fire investigation activities on behalf of the Department for Communities and Local Government (DCLG). An important element of its work is to publicise findings to designers.		BRE Global carries out fire investigation activities on behalf of the Department for Communities and Local Government (DCLG). An important element of its work is to publicise findings to designers.

−	Fire and smoke spread in concealed spaces within buildings can present both a life risk to occupants and firefighters, and cause widespread damage with extensive, difficult, and expensive clean-up and re-instatement. Indeed, in some cases, smoke deposits (and their resulting odour) can never be properly removed and buildings have had to be demolished. One such concealed space is the roof void.	+	Fire and smoke spread in concealed spaces within buildings can present both a life risk to occupants and firefighters, and cause widespread damage with extensive, difficult, and expensive clean-up and re-instatement. Indeed, in some cases, smoke deposits (and their resulting odour) can never be properly removed and buildings have had to be demolished. One such concealed space is the roof void. This article provides an introduction to the issue of concealed fire spread within roof voids considering the ‘lessons learned’ from real fires and the results of poor compartmentation.
−		+
−	This article provides an introduction to the issue of concealed fire spread within roof voids considering the ‘lessons learned’ from real fires and the results of poor compartmentation.	+

	In 2010, DCLG (then CLG) published a research study on fire compartmentation in the roof voids of residential buildings [1]. This found it is common practice within the industry for limited details to be included within building regulations applications. This puts the onus on the building contractor to ensure the correct detailing which increases the risk of errors and omissions.		In 2010, DCLG (then CLG) published a research study on fire compartmentation in the roof voids of residential buildings [1]. This found it is common practice within the industry for limited details to be included within building regulations applications. This puts the onus on the building contractor to ensure the correct detailing which increases the risk of errors and omissions.
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	The fire started in a small section of a flat roof of one apartment block, ignited the sarking felt on the adjacent pitched roof and spread into the roof void. The fire spread within the roof space over three apartments, bypassing two compartment walls.		The fire started in a small section of a flat roof of one apartment block, ignited the sarking felt on the adjacent pitched roof and spread into the roof void. The fire spread within the roof space over three apartments, bypassing two compartment walls.

−	Eventually, the fire spread into the roof void of an adjacent block, again involving three apartments and bypassing two compartment walls. The compartment walls were constructed from concrete building blocks. However, it was clear from the scene that no attempt had been made to fire-stop the junction between the walls and the roof as detailed in Approved Document B [2].	+	Eventually, the fire spread into the roof void of an adjacent block, again involving three apartments and bypassing two compartment walls. The compartment walls were constructed from concrete building blocks. However, it was clear from the scene that no attempt had been made to fire-stop the junction between the walls and the roof as detailed in Approved Document B [2]. Figure 1 shows the junction of the compartment wall with the roof covering.
−		+
−	Figure 1 shows the junction of the compartment wall with the roof covering.	+

	[[File:Lack_of_fire_stopping_between_compartment_wall_and_roof_covering.jpg\|link=File:Lack_of_fire_stopping_between_compartment_wall_and_roof_covering.jpg]]		[[File:Lack_of_fire_stopping_between_compartment_wall_and_roof_covering.jpg\|link=File:Lack_of_fire_stopping_between_compartment_wall_and_roof_covering.jpg]]
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	== Case study 2: Three-storey block of flats ==		== Case study 2: Three-storey block of flats ==

−	It is likely that the fire was initiated as a result of hot work being carried out on pipes penetrating the exterior wall of the three-storey block of flats. Initial fire spread was through the external wall cavity breaking out at roof level some distance from the point of origin. Once in the roof area, the fire spread rapidly, leading to collapse of the roof trusses and break out back into the floors below. It is clear from the speed and extent of the fire spread that the cavity barriers in the wall and compartmentation within the roof space were ineffective.	+	It is likely that the fire was initiated as a result of hot work being carried out on pipes penetrating the exterior wall of the three-storey block of flats. Initial fire spread was through the external wall cavity breaking out at roof level some distance from the point of origin. Once in the roof area, the fire spread rapidly, leading to collapse of the roof trusses and break out back into the floors below. It is clear from the speed and extent of the fire spread that the cavity barriers in the wall and compartmentation within the roof space were ineffective. Figure 2 shows the point of fire origin and the area where the fire broke out from the roof.
−		+
−	Figure 2 shows the point of fire origin and the area where the fire broke out from the roof.	+

	[[File:Block_of_flats_showing_the_area_of_fire_origin_and_damage_to_roof_level.jpg\|link=File:Block_of_flats_showing_the_area_of_fire_origin_and_damage_to_roof_level.jpg]]		[[File:Block_of_flats_showing_the_area_of_fire_origin_and_damage_to_roof_level.jpg\|link=File:Block_of_flats_showing_the_area_of_fire_origin_and_damage_to_roof_level.jpg]]
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	== Case study 3: Four-storey residential building ==		== Case study 3: Four-storey residential building ==

−	The fire is believed to have started on the landing of the second floor of a four-storey residential building. The fire spread from here to involve the third (top) floor landing and ultimately, to the roof structure, most probably via the roof soffit above a window onto the landing. Compartmentation was breached as the fire traversed the roof structure over a number of compartment walls. The compartment walls were constructed from concrete blocks clad in plasterboard with a plaster skim coat.	+	The fire is believed to have started on the landing of the second floor of a four-storey residential building. The fire spread from here to involve the third (top) floor landing and ultimately, to the roof structure, most probably via the roof soffit above a window onto the landing. Compartmentation was breached as the fire traversed the roof structure over a number of compartment walls. The compartment walls were constructed from concrete blocks clad in plasterboard with a plaster skim coat. The walls were continued up through the ceiling to the underside of the roof covering. The seal between the top of the wall and the roof covering seems to have been made from mineral wool (see Figure 3).
−		+
−	The walls were continued up through the ceiling to the underside of the roof covering. The seal between the top of the wall and the roof covering seems to have been made from mineral wool (see Figure 3).	+

	[[File:Mineral_wool_fire_stopping_along_pitch_of_roof.jpg\|link=File:Mineral_wool_fire_stopping_along_pitch_of_roof.jpg]]		[[File:Mineral_wool_fire_stopping_along_pitch_of_roof.jpg\|link=File:Mineral_wool_fire_stopping_along_pitch_of_roof.jpg]]
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	= Conclusions =		= Conclusions =

−	The fire protection of concealed spaces is of prime importance because any deficiencies in the installation and materials are not readily apparent and may quickly be covered over. Any inadequacies in such fire protection cannot be observed by the building users and, unlike other engineering provisions within the building, will not be directly apparent by its impact on every-day life. Any inadequacies in the fire protection of concealed spaces will only become apparent during the very time that their effectiveness is required – during a fire. Compartmentation in roof voids is a particular issue with respect to hidden fire spread. The biggest issue remains that of quality of construction. The research presented here and supported by the case studies shows that poor workmanship with inappropriate materials are the main reasons for the inadequate protection of concealed spaces. There is a clear and demonstrable need to ensure that buildings are designed and constructed so that the unseen spread of fire and smoke within concealed spaces within its structure and fabric is inhibited, as required by the Building Regulations.	+	The fire protection of concealed spaces is of prime importance because any deficiencies in the installation and materials are not readily apparent and may quickly be covered over. Any inadequacies in such fire protection cannot be observed by the building users and, unlike other engineering provisions within the building, will not be directly apparent by its impact on every-day life. Any inadequacies in the fire protection of concealed spaces will only become apparent during the very time that their effectiveness is required – during a fire. Compartmentation in roof voids is a particular issue with respect to hidden fire spread. The biggest issue remains that of quality of construction. The research presented here and supported by the case studies shows that poor workmanship with inappropriate materials are the main reasons for the inadequate protection of concealed spaces. There is a clear and demonstrable need to ensure that buildings are designed and constructed so that the unseen spread of fire and smoke within concealed spaces within its structure and fabric is inhibited, as required by the Building Regulations. There is adequate guidance available in the public domain to allow this to be achieved. See Existing guidance on fire compartmentation in roof voids
−		+
−	There is adequate guidance available in the public domain to allow this to be achieved. See Existing guidance on fire compartmentation in roof voids	+

	It also follows that the fire safety information required under Regulation 38 [9] is essential to those carrying out a fire risk assessment (under the Fire Safety Order) [10], so that the presence of concealed spaces can be identified and the fire protection they have been afforded can be assessed.		It also follows that the fire safety information required under Regulation 38 [9] is essential to those carrying out a fire risk assessment (under the Fire Safety Order) [10], so that the presence of concealed spaces can be identified and the fire protection they have been afforded can be assessed.

Designing Buildings at 13:38, 26 April 2016

2016-04-26T13:38:14Z

← Older revision		Revision as of 13:38, 26 April 2016
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	The fire protection of concealed spaces is of prime importance because any deficiencies in the installation and materials are not readily apparent and may quickly be covered over. Any inadequacies in such fire protection cannot be observed by the building users and, unlike other engineering provisions within the building, will not be directly apparent by its impact on every-day life. Any inadequacies in the fire protection of concealed spaces will only become apparent during the very time that their effectiveness is required – during a fire. Compartmentation in roof voids is a particular issue with respect to hidden fire spread. The biggest issue remains that of quality of construction. The research presented here and supported by the case studies shows that poor workmanship with inappropriate materials are the main reasons for the inadequate protection of concealed spaces. There is a clear and demonstrable need to ensure that buildings are designed and constructed so that the unseen spread of fire and smoke within concealed spaces within its structure and fabric is inhibited, as required by the Building Regulations.		The fire protection of concealed spaces is of prime importance because any deficiencies in the installation and materials are not readily apparent and may quickly be covered over. Any inadequacies in such fire protection cannot be observed by the building users and, unlike other engineering provisions within the building, will not be directly apparent by its impact on every-day life. Any inadequacies in the fire protection of concealed spaces will only become apparent during the very time that their effectiveness is required – during a fire. Compartmentation in roof voids is a particular issue with respect to hidden fire spread. The biggest issue remains that of quality of construction. The research presented here and supported by the case studies shows that poor workmanship with inappropriate materials are the main reasons for the inadequate protection of concealed spaces. There is a clear and demonstrable need to ensure that buildings are designed and constructed so that the unseen spread of fire and smoke within concealed spaces within its structure and fabric is inhibited, as required by the Building Regulations.

−	There is adequate guidance available in the public domain to allow this to be achieved. See Existing guidance on compartmentation in roof voids	+	There is adequate guidance available in the public domain to allow this to be achieved. See Existing guidance on fire compartmentation in roof voids

	It also follows that the fire safety information required under Regulation 38 [9] is essential to those carrying out a fire risk assessment (under the Fire Safety Order) [10], so that the presence of concealed spaces can be identified and the fire protection they have been afforded can be assessed.		It also follows that the fire safety information required under Regulation 38 [9] is essential to those carrying out a fire risk assessment (under the Fire Safety Order) [10], so that the presence of concealed spaces can be identified and the fire protection they have been afforded can be assessed.
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	=== Related articles on Designing Buildings Wiki ===		=== Related articles on Designing Buildings Wiki ===

−	* Existing guidance on compartmentation in roof voids.	+	* Existing guidance on fire compartmentation in roof voids.
	* Fire and rescue service.		* Fire and rescue service.
	* Fire compartment.		* Fire compartment.

Designing Buildings at 13:29, 26 April 2016

2016-04-26T13:29:52Z

← Older revision		Revision as of 13:29, 26 April 2016
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−	Fire in concealed spaces such as roof voids can be a killer. This article examines how to reduce the risk at design stage and during construction. By Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as [http://www.ciat.org.uk/en/other/document_summary.cfm/docid/6AAC237A-01F2-491D-AD7F5D02B455E2C1 Fire in the hole. Designing out fire risk in roof voids] in the Spring 2016 edition of [http://www.ciat.org.uk/en/media_centre/at-magazine/ AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)	+	Fire in concealed spaces such as roof voids can be a killer. This article examines how to reduce the risk at the design stage and during construction. It was written by Martin Shipp, Ciara Holland, David Crowder and Tom Lennon, Building Research Establishment (BRE) Global. It originally appeared as [http://www.ciat.org.uk/en/other/document_summary.cfm/docid/6AAC237A-01F2-491D-AD7F5D02B455E2C1 Fire in the hole. Designing out fire risk in roof voids] in the Spring 2016 edition of [http://www.ciat.org.uk/en/media_centre/at-magazine/ AT Magazine], published by the Chartered Institute of Architectural Technologists (CIAT)

	= Introduction =		= Introduction =
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	Figure 2 shows the point of fire origin and the area where the fire broke out from the roof.		Figure 2 shows the point of fire origin and the area where the fire broke out from the roof.

−	[[File:~~Block of flats showing the area of fire origin and damage to roof level~~.jpg]]	+	[[File:Block_of_flats_showing_the_area_of_fire_origin_and_damage_to_roof_level.jpg\|link=File:Block_of_flats_showing_the_area_of_fire_origin_and_damage_to_roof_level.jpg]]

	[Fig. 2. Block of flats showing the area of fire origin and damage to roof level.]		[Fig. 2. Block of flats showing the area of fire origin and damage to roof level.]
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	The walls were continued up through the ceiling to the underside of the roof covering. The seal between the top of the wall and the roof covering seems to have been made from mineral wool (see Figure 3).		The walls were continued up through the ceiling to the underside of the roof covering. The seal between the top of the wall and the roof covering seems to have been made from mineral wool (see Figure 3).

−	[[File:~~Mineral wool fire stopping along pitch of roof~~.jpg]]	+	[[File:Mineral_wool_fire_stopping_along_pitch_of_roof.jpg\|link=File:Mineral_wool_fire_stopping_along_pitch_of_roof.jpg]]

	[Fig. 3 Mineral wool fire stopping along pitch of roof in the background of the photograph]		[Fig. 3 Mineral wool fire stopping along pitch of roof in the background of the photograph]
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	Separation was provided in the roof space at approximately 15m intervals, comprising mineral wool and chicken wire curtains held in place with metal bars fixed to the timber trusses. The separation in the roof space clearly did not perform as intended. The poor state of the compartmentation in the roof space had been highlighted in a previous report following a fire on the same estate. The condition of the fire stopping in the roof space in a similar block is illustrated in Figure 4.		Separation was provided in the roof space at approximately 15m intervals, comprising mineral wool and chicken wire curtains held in place with metal bars fixed to the timber trusses. The separation in the roof space clearly did not perform as intended. The poor state of the compartmentation in the roof space had been highlighted in a previous report following a fire on the same estate. The condition of the fire stopping in the roof space in a similar block is illustrated in Figure 4.

−	[[File:~~Fire stopping in poor condition~~.jpg]]	+	[[File:Fire_stopping_in_poor_condition.jpg\|link=File:Fire_stopping_in_poor_condition.jpg]]

	[Fig. 4 Fire stopping in poor condition (image courtesy of London Fire Brigade)]		[Fig. 4 Fire stopping in poor condition (image courtesy of London Fire Brigade)]
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	Figure 5 shows the attempt made to provide fire stopping where the curved section of the roof crossed the compartment wall.		Figure 5 shows the attempt made to provide fire stopping where the curved section of the roof crossed the compartment wall.

−	[[File:~~Attempt to provide fire stopping in curved section of wall~~.jpg]]	+	[[File:Attempt_to_provide_fire_stopping_in_curved_section_of_wall.jpg\|link=File:Attempt_to_provide_fire_stopping_in_curved_section_of_wall.jpg]]

	[Fig. 5 Attempt to provide fire stopping in curved section of wall.]		[Fig. 5 Attempt to provide fire stopping in curved section of wall.]
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	The cavity barriers were constructed from mineral wool fixed to a wire mesh. The barriers were fixed to timber trusses using clamping plates. The fixing of the fire barrier to the timber trusses does not appear to have been in accordance with manufacturer’s guidance since the barriers did not press up against the underside of the sarking felt so the fire was able to spread along the sarking felt over the top of the cavity barriers (see Figure 6).		The cavity barriers were constructed from mineral wool fixed to a wire mesh. The barriers were fixed to timber trusses using clamping plates. The fixing of the fire barrier to the timber trusses does not appear to have been in accordance with manufacturer’s guidance since the barriers did not press up against the underside of the sarking felt so the fire was able to spread along the sarking felt over the top of the cavity barriers (see Figure 6).

−	[[File:~~Fire stopping against underside of sarking felt~~.jpg]]	+	[[File:Fire_stopping_against_underside_of_sarking_felt.jpg\|link=File:Fire_stopping_against_underside_of_sarking_felt.jpg]]

	[Fig. 6 Fire stopping against underside of sarking felt but not pushed up against underside of roof tiles.]		[Fig. 6 Fire stopping against underside of sarking felt but not pushed up against underside of roof tiles.]
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	Cavity barriers in the external wall cavity were either missing or poorly fitted. The fire spread up the cavity to the roof of the building, causing significant structural damage to the roof and accommodation storeys. A combination of fire-fighting and effective compartmentation, both between compartments and within the roof space, prevented more extensive fire spread within the building. Figure 7 is an aerial view of the building showing the damage at roof level.		Cavity barriers in the external wall cavity were either missing or poorly fitted. The fire spread up the cavity to the roof of the building, causing significant structural damage to the roof and accommodation storeys. A combination of fire-fighting and effective compartmentation, both between compartments and within the roof space, prevented more extensive fire spread within the building. Figure 7 is an aerial view of the building showing the damage at roof level.

−	[[File:~~Aerial view showing damage to roof structure~~.jpg]]	+	[[File:Aerial_view_showing_damage_to_roof_structure.jpg\|link=File:Aerial_view_showing_damage_to_roof_structure.jpg]]

	[Fig. 7 Aerial view showing damage to roof structure.]		[Fig. 7 Aerial view showing damage to roof structure.]
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	Fire started within a first floor bedroom of a two-storey residential care home. Smoke entered a wall cavity and found its way into the roof void where a detector was activated. Due to early activation and the prompt action of the Fire and Rescue Service, the fire was prevented from spreading into the roof void. However, there was inadequate separation within the roof space. The junction between the external wall cavity and the roof space is shown in Figure 8.		Fire started within a first floor bedroom of a two-storey residential care home. Smoke entered a wall cavity and found its way into the roof void where a detector was activated. Due to early activation and the prompt action of the Fire and Rescue Service, the fire was prevented from spreading into the roof void. However, there was inadequate separation within the roof space. The junction between the external wall cavity and the roof space is shown in Figure 8.

−	[[File:~~Close up of fire damage to pitch roof~~.jpg]]	+	[[File:Close_up_of_fire_damage_to_pitch_roof.jpg\|link=File:Close_up_of_fire_damage_to_pitch_roof.jpg]]

−	[Fig. 8 Close up of fire damage to pitch roof ~~(arrow showing direction of fire spread from wall cavity)~~]	+	[Fig. 8 Close up of fire damage to pitch roof]

	= Case study 9: Three-storey timber-frame terraced house =		= Case study 9: Three-storey timber-frame terraced house =
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	In this case, the quality of the compartmentation in the roof space prevented more widespread damage as can be seen from the undamaged roof trusses in Figure 9. The compartmentation was formed from two layers of plasterboard either side of the timber frame compartment wall, with all joints fully taped and sealed.		In this case, the quality of the compartmentation in the roof space prevented more widespread damage as can be seen from the undamaged roof trusses in Figure 9. The compartmentation was formed from two layers of plasterboard either side of the timber frame compartment wall, with all joints fully taped and sealed.

−	[[File:~~Undamaged roof trusses above seat of fire~~.jpg]]	+	[[File:Undamaged_roof_trusses_above_seat_of_fire.jpg\|link=File:Undamaged_roof_trusses_above_seat_of_fire.jpg]]

	[Fig. 9 Undamaged roof trusses above seat of fire.]		[Fig. 9 Undamaged roof trusses above seat of fire.]
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	The fire started within a ground floor flat and spread via the external façade into the compartment wall between occupancies. As with the incident in Case 9, the quality of compartmentation in the roof space, as shown in Figure 10, restricted the amount of damage from the fire.		The fire started within a ground floor flat and spread via the external façade into the compartment wall between occupancies. As with the incident in Case 9, the quality of compartmentation in the roof space, as shown in Figure 10, restricted the amount of damage from the fire.

−	[[File:~~Top floor of property showing fire damage to party wall~~.jpg]]	+	[[File:Top_floor_of_property_showing_fire_damage_to_party_wall.jpg\|link=File:Top_floor_of_property_showing_fire_damage_to_party_wall.jpg]]

	[Fig. 10. Top floor of property showing fire damage to party wall but roof trusses are unaffected by the fire due to compartmentation.]		[Fig. 10. Top floor of property showing fire damage to party wall but roof trusses are unaffected by the fire due to compartmentation.]