Roof insulation - Revision history

Daniel Wells at 14:12, 9 November 2022

2022-11-09T14:12:19Z

← Older revision		Revision as of 14:12, 9 November 2022
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	Typically, spray foam is formed of polyurethane and is sprayed as a liquid which gradually expands to up to 100 times its original volume. Once set, it creates an effective thermal and noise insulating layer. As spray foam can produce dangerous fumes and damage the structural integrity of the building if applied incorrectly, professional installation is recommended.		Typically, spray foam is formed of polyurethane and is sprayed as a liquid which gradually expands to up to 100 times its original volume. Once set, it creates an effective thermal and noise insulating layer. As spray foam can produce dangerous fumes and damage the structural integrity of the building if applied incorrectly, professional installation is recommended.
		+
		+	=== Cellular Concrete ===
		+
		+	On flat concrete roof slabs, cellular concrete (foamed concrete) can be used for both roof insulation and for creating a drainage slope. The density of the cellular concrete used typically ranges from 400 - 600 kg/m3 with corresponding thermal conductivities of 0.1 - 0.11 W/mK. The minimum thickness is 20 mm. The cellular concrete is typically covered by two layers of screed sandwiching a waterproofing membrane with tiles on top. This type of roof insulation is often used in the Middle East.

	= U-values =		= U-values =

Designing Buildings: Reverted edits by 223.236.202.182 (talk) to last revision by Editor

2021-03-17T07:01:44Z

Reverted edits by 223.236.202.182 (talk) to last revision by Editor

Can't load revision 198277

at 06:41, 17 March 2021

2021-03-17T06:41:56Z

Can't load revision 198276

Editor at 17:44, 16 February 2021

2021-02-16T17:44:41Z

← Older revision		Revision as of 17:44, 16 February 2021
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	* Shell roof		* Shell roof
	* Types of roof.		* Types of roof.
		+	* Underlay.
	* U-value.		* U-value.
	* U-What?		* U-What?

Editor at 13:46, 3 September 2020

2020-09-03T13:46:55Z

← Older revision		Revision as of 13:46, 3 September 2020
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	* Types of roof.		* Types of roof.
	* U-value.		* U-value.
		+	* U-What?
	* Vapour barrier.		* Vapour barrier.
	* Wall plate.		* Wall plate.
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	* British Urethane Foam Contractors Association - [http://www.bufca.co.uk http://www.bufca.co.uk]		* British Urethane Foam Contractors Association - [http://www.bufca.co.uk http://www.bufca.co.uk]

−	[[Category:Construction_techniques]] [[Category:Design]]	+	[[Category:DCN_Product_Knowledge]] [[Category:Construction_techniques]] [[Category:Design]]

Designing Buildings at 14:05, 3 July 2020

2020-07-03T14:05:45Z

← Older revision		Revision as of 14:05, 3 July 2020
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	* Wall plate.		* Wall plate.

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

	* Kingspan - [http://www.kingspaninsulation.co.uk/Knowledge-Base/Building-Regulations.aspx Building Regulations and Standards]		* Kingspan - [http://www.kingspaninsulation.co.uk/Knowledge-Base/Building-Regulations.aspx Building Regulations and Standards]
	* USwitch - [http://www.uswitch.com/insulation/guides/how-to-insulate-a-loft/ How to insulate a loft]		* USwitch - [http://www.uswitch.com/insulation/guides/how-to-insulate-a-loft/ How to insulate a loft]
−	* Renewable Energy Hub - ~~[https://www.renewableenergyhub.co.uk/types-of-insulation.html~~ Types of insulation]	+	* Renewable Energy Hub - Types of insulation
	* Energy.gov - [http://energy.gov/energysaver/types-insulation Insulation types]		* Energy.gov - [http://energy.gov/energysaver/types-insulation Insulation types]
	* The Green Age - [http://www.thegreenage.co.uk/spray-foam-insulation-faq/ Spray foam insulation]		* The Green Age - [http://www.thegreenage.co.uk/spray-foam-insulation-faq/ Spray foam insulation]

Editor at 18:49, 22 October 2019

2019-10-22T18:49:22Z

← Older revision		Revision as of 18:49, 22 October 2019
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	* Limiting fabric parameters.		* Limiting fabric parameters.
	* Loft insulation ruling.		* Loft insulation ruling.
		+	* Mineral wool.
	* Roof tiles.		* Roof tiles.
	* Roofing defects.		* Roofing defects.

Editor at 17:34, 28 August 2019

2019-08-28T17:34:07Z

← Older revision		Revision as of 17:34, 28 August 2019
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	* Existing buildings: Refurbishment – 0.18		* Existing buildings: Refurbishment – 0.18

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

	* Approved Document L.		* Approved Document L.
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	* Cavity wall insulation.		* Cavity wall insulation.
	* Code for Sustainable Homes.		* Code for Sustainable Homes.
		+	* Fire insulation.
	* Firring.		* Firring.
	* Flat roof defects.		* Flat roof defects.

Editor at 16:23, 27 October 2017

2017-10-27T16:23:30Z

← Older revision		Revision as of 16:23, 27 October 2017
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	This type of roof is generally straightforward to insulate because of space availability and access, and so there are range of insulation options to choose from:		This type of roof is generally straightforward to insulate because of space availability and access, and so there are range of insulation options to choose from:

−	* Warm roof: This is where insulation is installed immediately under the roof, within the plane of the roof pitch, meaning that the loft space beneath is also kept warm.	+	=== Warm roof ===
−	* Cold roof: This is where insulation is installed immediately above the ceiling of the top storey, meaning the loft space is not heated. This generally involves insulating between and over joists immediately above the ceiling of the top floor. Cold roof solutions are generally less expensive to install because there is a lot of available space, and so more economic, deeper insulation materials can be used.	+
		+	This is where insulation is installed immediately under the roof, within the plane of the roof pitch, meaning that the loft space beneath is also kept warm.
		+
		+	=== Cold roof ===
		+
		+	This is where insulation is installed immediately above the ceiling of the top storey, meaning the loft space is not heated. This generally involves insulating between and over joists immediately above the ceiling of the top floor.
		+
		+	Cold roof solutions are generally less expensive to install because there is a lot of available space, and so more economic, deeper insulation materials can be used.

	= Flat roofs =		= Flat roofs =
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	* Inverted roof: The insulation is installed above the uppermost weatherproof membrane, of the roof structure, effectively protecting it from heat and cold which can cause damage in the long term.		* Inverted roof: The insulation is installed above the uppermost weatherproof membrane, of the roof structure, effectively protecting it from heat and cold which can cause damage in the long term.

−	For more information see Flat roof defects.	+	For more information, see Flat roof defects.

	= Condensation =		= Condensation =

−	As warm, moist internal air permeates through the external envelope of a building towards the outside, it will tend to cool. When it reaches its ‘dew point’ temperature, the moisture it holds will begin to condense as water. If this happens within the structure of the building itself, this is known as interstitial condensation. If interstitial condensation occurs within the inner skin of the building envelope, it can cause problems. To prevent this, vapour control layers (VCL) or vapour barriers are positioned on the warm side of the structure, preventing the warm moist air from penetrating to a point where it might reach its dew point temperature.	+	As warm, moist internal air permeates through the external envelope of a building towards the outside, it will tend to cool. When it reaches its ‘dew point’ temperature, the moisture it holds will begin to condense as water. If this happens within the structure of the building itself, this is known as interstitial condensation.
		+
		+	If interstitial condensation occurs within the inner skin of the building envelope, it can cause problems. To prevent this, vapour control layers (VCL) or vapour barriers are positioned on the warm side of the structure, preventing the warm moist air from penetrating to a point where it might reach its dew point temperature.

	Great care must be taken when retrofitting insulation to an existing roof. If the insulation changes a warm roof into a cold roof, it may be necessary to install additional ventilation so that cold damp air can escape from the roof space and does not cause timber to decay.		Great care must be taken when retrofitting insulation to an existing roof. If the insulation changes a warm roof into a cold roof, it may be necessary to install additional ventilation so that cold damp air can escape from the roof space and does not cause timber to decay.
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	=== Blanket insulation (also called matting insulation) ===		=== Blanket insulation (also called matting insulation) ===

−	This is the most common and easiest to install. It generally comes in foil-backed rolls which can be placed between joists or rafters, and may be held in place by timber battens attached to and across the joists or rafters. It is usually made of mineral or glass wool but can also be made from plastic fibres, and natural fibres such as cotton and sheep’s wool. The depth of blanket-style insulation may be in the range of 250-~~270mm~~.	+	This is the most common and easiest to install. It generally comes in foil-backed rolls which can be placed between joists or rafters, and may be held in place by timber battens attached to and across the joists or rafters. It is usually made of mineral or glass wool but can also be made from plastic fibres, and natural fibres such as cotton and sheep’s wool. The depth of blanket-style insulation may be in the range of 250-270 mm.

	=== Foam boards ===		=== Foam boards ===

−	These are rigid panels of insulation which are cut and fitted in place. Most commonly they are made from polystyrene, polyisocyanurate, and polyurethane, and may fitted to a depth of around ~~175mm~~.	+	These are rigid panels of insulation which are cut and fitted in place. Most commonly they are made from polystyrene, polyisocyanurate, and polyurethane, and may fitted to a depth of around 175 mm.

	=== Radiant barriers ===		=== Radiant barriers ===

−	These inhibit heat transfer by thermal radiation. They are capable of being stapled to the underside of rafters. They are more effective in hot climates, and studies have shown that the reduced heat gain may allow for smaller air conditioning systems. In cool climates, installing more thermal insulation it is usually more cost effective. The thickness of a radiant barrier is usually between 3-~~5mm~~.	+	These inhibit heat transfer by thermal radiation. They are capable of being stapled to the underside of rafters. They are more effective in hot climates, and studies have shown that the reduced heat gain may allow for smaller air conditioning systems. In cool climates, installing more thermal insulation it is usually more cost effective. The thickness of a radiant barrier is usually between 3-5 mm.

	=== Blown-in insulation ===		=== Blown-in insulation ===
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	Approved Document L specifies minimum U-values for domestic and non-domestic buildings in England. Calculations by [http://www.kingspaninsulation.co.uk/Knowledge-Base/Building-Regulations.aspx Kingspan] have produced best starting point values that are thought to be suitable for common situations.		Approved Document L specifies minimum U-values for domestic and non-domestic buildings in England. Calculations by [http://www.kingspaninsulation.co.uk/Knowledge-Base/Building-Regulations.aspx Kingspan] have produced best starting point values that are thought to be suitable for common situations.

−	U-values for roofs in domestic buildings	+	=== U-values for roofs in domestic buildings ===

	Pitched roof – ceiling level		Pitched roof – ceiling level
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	* Heat transfer.		* Heat transfer.
	* Limiting fabric parameters.		* Limiting fabric parameters.
		+	* Loft insulation ruling.
	* Roof tiles.		* Roof tiles.
	* Roofing defects.		* Roofing defects.

Editor at 15:35, 20 January 2017

2017-01-20T15:35:03Z

← Older revision		Revision as of 15:35, 20 January 2017
Line 99:		Line 99:
	* Heat transfer.		* Heat transfer.
	* Limiting fabric parameters.		* Limiting fabric parameters.
		+	* Roof tiles.
	* Roofing defects.		* Roofing defects.
	* Solid wall insulation.		* Solid wall insulation.
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	* Wall plate.		* Wall plate.

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

	* Kingspan - [http://www.kingspaninsulation.co.uk/Knowledge-Base/Building-Regulations.aspx Building Regulations and Standards]		* Kingspan - [http://www.kingspaninsulation.co.uk/Knowledge-Base/Building-Regulations.aspx Building Regulations and Standards]