Condensation in buildings - Revision history

Designing Buildings at 06:29, 4 August 2022

2022-08-04T06:29:44Z

← Older revision		Revision as of 06:29, 4 August 2022
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	= Related articles on Designing Buildings =		= Related articles on Designing Buildings =

−	* Airbrick.
	* Approved Document F.		* Approved Document F.
	* Cold bridge.		* Cold bridge.
		+	* Condensation pipework.
	* Damp.		* Damp.
	* Damp proofing.		* Damp proofing.

Editor at 17:55, 3 February 2022

2022-02-03T17:55:05Z

← Older revision		Revision as of 17:55, 3 February 2022
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	* Damp.		* Damp.
	* Damp proofing.		* Damp proofing.
		+	* Dehumidification.
	* Designing out unintended consequences when applying solid wall insulation FB 79.		* Designing out unintended consequences when applying solid wall insulation FB 79.
	* Dew point.		* Dew point.

Editor at 16:30, 2 February 2022

2022-02-02T16:30:11Z

← Older revision		Revision as of 16:30, 2 February 2022
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	Condensation in buildings is regulated by Part C of the building regulations, and guidance about how to deal with common situations is given in Approved Document C (Site preparation and resistance to contaminates and moisture) and Approved Document F (Ventilation). Further guidance is available in BS 5250 Code of practice for the control of condensation in buildings.		Condensation in buildings is regulated by Part C of the building regulations, and guidance about how to deal with common situations is given in Approved Document C (Site preparation and resistance to contaminates and moisture) and Approved Document F (Ventilation). Further guidance is available in BS 5250 Code of practice for the control of condensation in buildings.

−	= Related articles on Designing Buildings ~~Wiki~~ =	+	= Related articles on Designing Buildings =

	* Airbrick.		* Airbrick.
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	* Electrical resistance meters.		* Electrical resistance meters.
	* Flashing.		* Flashing.
		+	* Humidification.
	* Humidity.		* Humidity.
	* Hygrothermal.		* Hygrothermal.

Designing Buildings: Reverted edits by 82.132.235.126 (talk) to last revision by Editor

2021-03-01T22:25:28Z

Reverted edits by 82.132.235.126 (talk) to last revision by Editor

← Older revision		Revision as of 22:25, 1 March 2021
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	When air cools, it is less able to 'hold' moisture, that is, the saturation water vapour density falls, and so the relative humidity rises. When the relative humidity reaches 100%, the air will be saturated. This is described as the dew point. If the air continues to cool, moisture will begin to condense.		When air cools, it is less able to 'hold' moisture, that is, the saturation water vapour density falls, and so the relative humidity rises. When the relative humidity reaches 100%, the air will be saturated. This is described as the dew point. If the air continues to cool, moisture will begin to condense.

−	Typically this happens in buildings when warm, moist air comes into contact with cooler surfaces that are at or below the dew point (such as windows) and water condenses on those surfaces. k	+	Typically this happens in buildings when warm, moist air comes into contact with cooler surfaces that are at or below the dew point (such as windows) and water condenses on those surfaces.

	Moisture can also form as interstitial condensation - occurring within the layers of the building fabric - typically as a result of air diffusing from the warm interior of a building to the cool exterior and reaching its dew point within the construction of the building itself. For more information see: Interstitial condensation.		Moisture can also form as interstitial condensation - occurring within the layers of the building fabric - typically as a result of air diffusing from the warm interior of a building to the cool exterior and reaching its dew point within the construction of the building itself. For more information see: Interstitial condensation.
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	* Wet-bulb temperature.		* Wet-bulb temperature.

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

82.132.235.126 at 21:02, 1 March 2021

2021-03-01T21:02:14Z

← Older revision		Revision as of 21:02, 1 March 2021
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	When air cools, it is less able to 'hold' moisture, that is, the saturation water vapour density falls, and so the relative humidity rises. When the relative humidity reaches 100%, the air will be saturated. This is described as the dew point. If the air continues to cool, moisture will begin to condense.		When air cools, it is less able to 'hold' moisture, that is, the saturation water vapour density falls, and so the relative humidity rises. When the relative humidity reaches 100%, the air will be saturated. This is described as the dew point. If the air continues to cool, moisture will begin to condense.

−	Typically this happens in buildings when warm, moist air comes into contact with cooler surfaces that are at or below the dew point (such as windows) and water condenses on those surfaces.	+	Typically this happens in buildings when warm, moist air comes into contact with cooler surfaces that are at or below the dew point (such as windows) and water condenses on those surfaces. k

	Moisture can also form as interstitial condensation - occurring within the layers of the building fabric - typically as a result of air diffusing from the warm interior of a building to the cool exterior and reaching its dew point within the construction of the building itself. For more information see: Interstitial condensation.		Moisture can also form as interstitial condensation - occurring within the layers of the building fabric - typically as a result of air diffusing from the warm interior of a building to the cool exterior and reaching its dew point within the construction of the building itself. For more information see: Interstitial condensation.
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	* Wet-bulb temperature.		* Wet-bulb temperature.

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

Editor at 19:07, 26 October 2020

2020-10-26T19:07:25Z

← Older revision		Revision as of 19:07, 26 October 2020
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	* Diagnosing the causes of dampness (GR 5 revised).		* Diagnosing the causes of dampness (GR 5 revised).
	* Dry-bulb temperature.		* Dry-bulb temperature.
		+	* Electrical resistance meters.
	* Flashing.		* Flashing.
	* Humidity.		* Humidity.

Designing Buildings at 09:54, 15 September 2020

2020-09-15T09:54:05Z

← Older revision		Revision as of 09:54, 15 September 2020
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	* Wet-bulb temperature.		* Wet-bulb temperature.

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

Designing Buildings at 13:00, 27 December 2019

2019-12-27T13:00:56Z

← Older revision		Revision as of 13:00, 27 December 2019
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	Typically this happens in buildings when warm, moist air comes into contact with cooler surfaces that are at or below the dew point (such as windows) and water condenses on those surfaces.		Typically this happens in buildings when warm, moist air comes into contact with cooler surfaces that are at or below the dew point (such as windows) and water condenses on those surfaces.

−	Moisture can also form as interstitial condensation - occurring within the layers of the building fabric - typically as a result of air diffusing from the warm interior of a building to the cool exterior and reaching its dew point within the construction of the building itself.	+	Moisture can also form as interstitial condensation - occurring within the layers of the building fabric - typically as a result of air diffusing from the warm interior of a building to the cool exterior and reaching its dew point within the construction of the building itself. For more information see: Interstitial condensation.

	Condensation affects the performance of buildings, causing problems such as:		Condensation affects the performance of buildings, causing problems such as:
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	* Wet-bulb temperature.		* Wet-bulb temperature.

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

Designing Buildings at 12:57, 27 December 2019

2019-12-27T12:57:15Z

Editor at 13:18, 13 December 2019

2019-12-13T13:18:20Z

← Older revision		Revision as of 13:18, 13 December 2019
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	* Hygrothermal.		* Hygrothermal.
	* Interstitial condensation.		* Interstitial condensation.
		+	* Methodology for moisture investigations in traditional buildings.
	* Moisture.		* Moisture.
	* Moisture content.		* Moisture content.

← Older revision		Revision as of 12:57, 27 December 2019
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	When air cools, it is less able to 'hold' moisture, that is, the saturation water vapour density falls, and so the relative humidity rises. When the relative humidity reaches 100%, the air will be saturated. This is described as the dew point. If the air continues to cool, moisture will begin to condense.		When air cools, it is less able to 'hold' moisture, that is, the saturation water vapour density falls, and so the relative humidity rises. When the relative humidity reaches 100%, the air will be saturated. This is described as the dew point. If the air continues to cool, moisture will begin to condense.

−	Typically this happens in buildings when warm, moist air comes into contact with cooler surfaces that are at or below the dew point, such as windows, and water condenses on those surfaces.	+	Typically this happens in buildings when warm, moist air comes into contact with cooler surfaces that are at or below the dew point (such as windows) and water condenses on those surfaces.

−	~~Condensation~~ can ~~occur on surfaces, or can be~~ interstitial condensation occurring ~~between~~ the layers of the building ~~envelope,~~ typically as a result of air diffusing from the warm interior of ~~the~~ building to the cool exterior and reaching its dew point within the building ~~fabric. This interstitial condensation, when trapped within the structure by impervious materials is often erroneously referred to as rising damp~~.	+	Moisture can also form as interstitial condensation - occurring within the layers of the building fabric - typically as a result of air diffusing from the warm interior of a building to the cool exterior and reaching its dew point within the construction of the building itself.

	Condensation affects the performance of buildings, causing problems such as:		Condensation affects the performance of buildings, causing problems such as:

−	* Mould growth which is a cause of respiratory allergies.	+	* Mould growth, which can be a cause of respiratory allergies.
	* Mildew.		* Mildew.
	* Staining.		* Staining.
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	Condensation can be controlled by:		Condensation can be controlled by:

−	* Limiting sources of moisture (including reverse condensation, where moisture evaporates from damp materials). For example, replacing flueless gas or oil heaters.	+	* Limiting sources of moisture (including reverse condensation, where moisture evaporates from damp materials). For example, replacing flueless gas or oil heaters, providing ventilated spaces for drying clothes, cooking and so on.
	* Increasing air temperatures.		* Increasing air temperatures.
	* Dehumidification.		* Dehumidification.
−	* Natural or mechanical ventilation. This is particularly important in cold roofs, where unseen problems can build up, putting occupants in danger of structural collapse.	+	* Natural or mechanical ventilation. This is particularly important in cold roofs, where unseen problems can build up, putting occupants in danger of structural collapse. See cold roof for more information.
	* Increasing surface temperatures, such as by the inclusion of insulation or by improving glazing.		* Increasing surface temperatures, such as by the inclusion of insulation or by improving glazing.
−	* Avoiding cold bridges. These are situations where there is a direct connection between the inside and outside through one or more elements that are more thermally conductive than the rest of the building envelope. Thermal bridges are common in older buildings, which may be poorly constructed, poorly insulated, with single skin construction and single glazing. In modern buildings, thermal bridging can occur because of poor design, or poor workmanship. This is common where elements ~~of the building~~ penetrate through ~~its~~ insulated fabric, for example around glazing, or where the structure penetrates the building envelope, such as at balconies.	+	* Avoiding cold bridges. These are situations where there is a direct connection between the inside and outside through one or more elements that are more thermally conductive than the rest of the building envelope. Thermal bridges are common in older buildings, which may be poorly constructed, poorly insulated and with single skin construction and single glazing. In modern buildings, thermal bridging can occur because of poor design, or poor workmanship. This is common where elements penetrate through the insulated fabric of the building, for example around glazing, or where the structure penetrates the building envelope, such as at balconies. For more information see: Cold bridge.
−	* The introduction of vapour barriers (vapour control layers) which prevent moisture from diffusing through the building fabric to a point where temperatures might be low enough to reach dew point.	+	* The introduction of vapour barriers (vapour control layers) which prevent moisture from diffusing through the building fabric to a point where temperatures might be low enough to reach dew point. For more information see: Vapour barrier.

−	Some uses of buildings generate high levels of moisture and so specialist techniques may be necessary to prevent or mitigate the occurrence of condensation.	+	Some uses of buildings (such as swimming pools) can generate high levels of moisture and so specialist techniques may be necessary to prevent or mitigate the occurrence of condensation.

	It is important that any systems introduced to limit condensation are properly installed and maintained to ensure continued optimal operation.		It is important that any systems introduced to limit condensation are properly installed and maintained to ensure continued optimal operation.

−	Condensation in buildings is regulated by Approved Document C (Site preparation and resistance to contaminates and moisture) and Approved Document F (Ventilation) ~~and further~~ guidance is available in BS 5250 Code of practice for the control of condensation in buildings.	+	Condensation in buildings is regulated by Part C of the building regulations, and guidance about how to deal with common situations is given in Approved Document C (Site preparation and resistance to contaminates and moisture) and Approved Document F (Ventilation). Further guidance is available in BS 5250 Code of practice for the control of condensation in buildings.

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