Lead - Revision history

Editor at 13:09, 9 June 2023

2023-06-09T13:09:47Z

← Older revision		Revision as of 13:09, 9 June 2023
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	= Toxicity =		= Toxicity =

−	Lead is a toxic element which, after prolonged exposure, can cause damage to the central nervous system and kidneys. It is particularly hazardous for young children as it can affect their development and its sweet flavour may prompt them to try and eat it. It may also be a carcinogen. Although a highly dangerous pollutant, ~~lead~~ has the benefit of being easily recycled – in the UK, 95% of lead is recycled.	+	Lead is a toxic element which, after prolonged exposure, can cause damage to the central nervous system and kidneys. It is particularly hazardous for young children as it can affect their development and its sweet flavour may prompt them to try and eat it. It may also be a carcinogen. It also causes animal poisoning and can interfere with numerous human enzymes, and cause brain damage. Although a naturally occurring toxic metal and highly dangerous pollutant it is used in alloys, ceramic components, and solders, but has the benefit of being easily recycled, in the UK, 95% of lead is recycled.
		+
		+	Lead use is covered by the EU and UK Restriction of Hazardous Substances in Electrical and Electronic Equipment (RoHS) directive and regulations, meaning its use is restricted to 0.01% in products through application and monitored, along with other substances that include cadmium, mercury, hexavalent chromium, polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE), bis(2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP).

	= Historical usage =		= Historical usage =
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	NB The term 'lead' may also refer to the amount of time required between the start or finish of a successor task and the start or finish of a predecessor task. For example, see: Lead time. Ref The Society of Construction Law Delay and Disruption Protocol, 2nd edition.		NB The term 'lead' may also refer to the amount of time required between the start or finish of a successor task and the start or finish of a predecessor task. For example, see: Lead time. Ref The Society of Construction Law Delay and Disruption Protocol, 2nd edition.

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

	* Aluminium.		* Aluminium.

Designing Buildings at 07:51, 12 January 2022

2022-01-12T07:51:18Z

← Older revision		Revision as of 07:51, 12 January 2022
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	* Shingle roofing.		* Shingle roofing.
	* Spangle.		* Spangle.
		+	* Types of metal.
	* Types of roof.		* Types of roof.
	* Zinc		* Zinc

	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:History]]		[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:History]]

Editor at 19:12, 6 July 2021

2021-07-06T19:12:25Z

← Older revision		Revision as of 19:12, 6 July 2021
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	* Roof tiles.		* Roof tiles.
	* Shingle roofing.		* Shingle roofing.
		+	* Spangle.
	* Types of roof.		* Types of roof.
	* Zinc		* Zinc

	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:History]]		[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:History]]

Designing Buildings at 08:30, 20 November 2020

2020-11-20T08:30:19Z

← Older revision		Revision as of 08:30, 20 November 2020
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	* Zinc		* Zinc

−	[[Category:History]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:History]]

Designing Buildings at 10:06, 8 July 2020

2020-07-08T10:06:54Z

← Older revision		Revision as of 10:06, 8 July 2020
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	* Galvanised steel.		* Galvanised steel.
	* Lead in construction.		* Lead in construction.
		+	* [[Leading\|Leading]].
		+	* Lead came.
		+	* Lead-light cement.
	* Lead time.		* Lead time.
	* Long span roof.		* Long span roof.

Designing Buildings at 09:32, 19 March 2019

2019-03-19T09:32:23Z

← Older revision		Revision as of 09:32, 19 March 2019
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	\| [[File:Lead_sheet_roofing.jpg\|link=File:Lead_sheet_roofing.jpg]]		\| [[File:Lead_sheet_roofing.jpg\|link=File:Lead_sheet_roofing.jpg]]
	\|}		\|}
		+
		+	NB The term 'lead' may also refer to the amount of time required between the start or finish of a successor task and the start or finish of a predecessor task. For example, see: Lead time. Ref The Society of Construction Law Delay and Disruption Protocol, 2nd edition.

	= Related articles on Designing Buildings Wiki =		= Related articles on Designing Buildings Wiki =
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	* Galvanised steel.		* Galvanised steel.
	* Lead in construction.		* Lead in construction.
		+	* Lead time.
	* Long span roof.		* Long span roof.
	* Major cast metal components.		* Major cast metal components.

Editor at 15:08, 7 March 2019

2019-03-07T15:08:10Z

← Older revision		Revision as of 15:08, 7 March 2019
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	= Toxicity =		= Toxicity =

−	Lead is a toxic element which, after prolonged exposure, can cause damage to the central nervous system and kidneys. It is particularly hazardous for young children as it can affect their development and its sweet flavour may prompt them to ~~taste~~ it. It may also be a carcinogen. Although a highly dangerous pollutant, lead has the benefit of being easily recycled – in the UK, 95% of lead is recycled.	+	Lead is a toxic element which, after prolonged exposure, can cause damage to the central nervous system and kidneys. It is particularly hazardous for young children as it can affect their development and its sweet flavour may prompt them to try and eat it. It may also be a carcinogen. Although a highly dangerous pollutant, lead has the benefit of being easily recycled – in the UK, 95% of lead is recycled.

	= Historical usage =		= Historical usage =

Designing Buildings at 08:47, 7 March 2019

2019-03-07T08:47:25Z

← Older revision		Revision as of 08:47, 7 March 2019
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	{\|		{\|
−	\| [[File:~~Lead roof~~.JPG]]	+	\| [[File:Lead_roof.JPG\|link=File:Lead_roof.JPG]]
	\|}		\|}

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	{\|		{\|
−	\| [[File:~~Lead sheet roofing~~.jpg]]	+	\| [[File:Lead_sheet_roofing.jpg\|link=File:Lead_sheet_roofing.jpg]]
	\|}		\|}

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	* Flashing.		* Flashing.
	* Galvanised steel.		* Galvanised steel.
		+	* Lead in construction.
	* Long span roof.		* Long span roof.
	* Major cast metal components.		* Major cast metal components.

Designing Buildings at 08:46, 7 March 2019

2019-03-07T08:46:07Z

← Older revision		Revision as of 08:46, 7 March 2019
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	= Introduction =		= Introduction =

−	Lead is a chemical element that occurs in relatively small quantities in the earth’s crust. It has been mined since ancient times. The Latin name for it was ‘plumbum’ (hence chemical symbol Pb) and its ore was given the name ‘galena’ by the Roman naturalist Pliny.	+	Lead is a chemical element that occurs in relatively small quantities in the earth’s crust. It has been mined since ancient times. The Latin name for lead was ‘plumbum’ (hence the chemical symbol Pb) and its ore was given the name ‘galena’ by the Roman naturalist Pliny.

−	Lead is a heavy metal which takes on a dull grey appearance when exposed to air. Although expensive, it is both durable and malleable. It also has a low melting point. These qualities have enabled its use in building applications such as roofing, damp proofing and plumbing. Other uses ~~include white~~ paints, ~~leaded~~ petrol, radiation shielding, batteries, bullets and shot, weights, solders, pewter and decorative work on buildings. Today, leaded petrol is only used for special vehicles; for general use, unleaded petrol is available and went on sale in the UK in June 1986.	+	Lead is a heavy metal which takes on a dull grey appearance when exposed to air. Although relatively expensive, it is both durable and malleable. It also has a low melting point. These qualities have enabled its use in building applications such as roofing, damp proofing and plumbing. Other uses have included paints, petrol, radiation shielding, batteries, bullets and shot, weights, solders, pewter and decorative work on buildings, windows, flashing, pipework and so on. Today, leaded petrol is only used for special vehicles; for general use, unleaded petrol is available and went on sale in the UK in June 1986.

	= Toxicity =		= Toxicity =

−	Lead is a toxic element which, after prolonged exposure, can cause damage to the central nervous system and kidneys. It is particularly hazardous for young children as it can affect their development and its sweet ~~taste~~ may prompt them to taste it. It may also be a carcinogen. Although a highly dangerous pollutant, lead has the benefit of being easily recycled – in the UK, 95% of lead is recycled.	+	Lead is a toxic element which, after prolonged exposure, can cause damage to the central nervous system and kidneys. It is particularly hazardous for young children as it can affect their development and its sweet flavour may prompt them to taste it. It may also be a carcinogen. Although a highly dangerous pollutant, lead has the benefit of being easily recycled – in the UK, 95% of lead is recycled.

	= Historical usage =		= Historical usage =

−	In Roman times, lead was used as a pigment: ‘lead white’ was a powder produced by the ‘stack’ process. The powder was separated from the lead and added to paints to give a white colour. Despite its poisonous nature, lead was used in paints and artists colours ~~right~~ up to the 19th century. When added to oil paints, it imparts resilience and ease of handling; white lead oil-paint was marketed to artists as ‘flake white’ or ‘Cremnitz white’.	+	In Roman times, lead was used as a pigment: ‘lead white’ was a powder produced by the ‘stack’ process. The powder was separated from the lead and added to paints to give a white colour. Despite its poisonous nature, lead was used in paints and artists colours up to the 19th century. When added to oil paints, it imparts resilience and ease of handling; white lead oil-paint was marketed to artists as ‘flake white’ or ‘Cremnitz white’.

	While the EU has not banned lead paint, it has issued directives that control its use. Most commercially-available decorative and art paints are now ‘lead free’.		While the EU has not banned lead paint, it has issued directives that control its use. Most commercially-available decorative and art paints are now ‘lead free’.

−	During the medieval period, lead was used for plumbing, as a roof covering and for gutters and downpipes, primarily for churches, cathedrals and other important buildings. Its relative inertness to oxidation meant it was a stable element that could last for many decades. Its use rose sharply during the industrial revolution when it was used not just for roof sheeting, but also as a flashing (strips of lead tucked into brickwork or stone to make junctions watertight) and as a damp-proofing course to resist rising damp in ~~brickwork~~. Other uses included decorative work, such as finials and weather vanes, and for the lead frames (lead cames) used in stained glass ~~(pictured)~~.	+	During the medieval period, lead was used for plumbing, as a roof covering and for gutters and downpipes, primarily for churches, cathedrals and other important buildings. Its relative inertness to oxidation meant it was a stable element that could last for many decades. Its use rose sharply during the industrial revolution when it was used not just for roof sheeting, but also as a flashing (strips of lead tucked into brickwork or stone to make junctions watertight) and as a damp-proofing course to resist rising damp in masonry. Other uses included decorative work, such as finials and weather vanes, and for the lead frames (lead cames) used in stained glass.
		+
		+	{\|
		+	\| [[File:Lead roof.JPG]]
		+	\|}

	= Building construction =		= Building construction =
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	In the UK, the use of lead in building construction has declined, primarily due to its toxicity as even water run-off from a lead roof can be a source of pollution. It can also be relatively expensive, while its easy recyclability has led to many thefts from church roofs. In place of lead sheet, other metals such as zinc, copper and steel can be used although none have the softness and malleability that made lead such a favourite with roofers.		In the UK, the use of lead in building construction has declined, primarily due to its toxicity as even water run-off from a lead roof can be a source of pollution. It can also be relatively expensive, while its easy recyclability has led to many thefts from church roofs. In place of lead sheet, other metals such as zinc, copper and steel can be used although none have the softness and malleability that made lead such a favourite with roofers.

−	~~However, lead~~ is still used for traditional buildings and conservation purposes. It is available in rolls in standard 3m and 6m lengths with a maximum width of 1370mm and in thicknesses from 1.32mm (code 3) to 3.55mm (code 8), although thicknesses up to 9mm are available.	+	Lead is still used for traditional buildings and conservation purposes. It is available in rolls in standard 3m and 6m lengths with a maximum width of 1370mm and in thicknesses from 1.32mm (code 3) to 3.55mm (code 8), although thicknesses up to 9mm are available.

	When molten lead is poured against a sand mould (sandcast) it produces a prized, fine, mottled surface that is often used for church roofs and heritage projects. It is supplied typically in 2.65mm (code 6) – 3.55mm (code 8) thicknesses and in usable widths of 1200mm.		When molten lead is poured against a sand mould (sandcast) it produces a prized, fine, mottled surface that is often used for church roofs and heritage projects. It is supplied typically in 2.65mm (code 6) – 3.55mm (code 8) thicknesses and in usable widths of 1200mm.

−	For most domestic applications, lead can be used to create abutment flashings, chimney flashings, internal and external corners, damp proof courses (DPCs – both flat and stepped), welted hips, valley gutters, as well as cheek- and top-coverings for dormer windows.	+	For most domestic applications, lead can be used to create abutment flashings, chimney flashings, internal and external corners, damp proof courses (DPCs – both flat and stepped), welted hips, valley gutters, as well as cheek- and top-coverings for dormer windows and so on.
		+
		+	{\|
		+	\| [[File:Lead sheet roofing.jpg]]
		+	\|}

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

Editor at 19:39, 6 March 2019

2019-03-06T19:39:50Z

← Older revision		Revision as of 19:39, 6 March 2019
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	{\|		{\|
−	\| [[File:~~Stained glass window~~.jpg]]	+	\| [[File:Stained_glass_window.jpg\|link=File:Stained_glass_window.jpg]]
	\|}		\|}

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	While the EU has not banned lead paint, it has issued directives that control its use. Most commercially-available decorative and art paints are now ‘lead free’.		While the EU has not banned lead paint, it has issued directives that control its use. Most commercially-available decorative and art paints are now ‘lead free’.

−	During the medieval period, lead was used for plumbing, as a roof covering and for gutters and downpipes, primarily for churches, cathedrals and other important buildings. Its relative inertness to oxidation meant it was a stable element that could last for many decades. Its use rose sharply during the industrial revolution when it was used not just for roof sheeting, but also as a flashing (strips of lead tucked into brickwork or stone to make junctions watertight) and as a damp-proofing course to resist rising damp in brickwork. Other uses included decorative work, such as finials and weather vanes.	+	During the medieval period, lead was used for plumbing, as a roof covering and for gutters and downpipes, primarily for churches, cathedrals and other important buildings. Its relative inertness to oxidation meant it was a stable element that could last for many decades. Its use rose sharply during the industrial revolution when it was used not just for roof sheeting, but also as a flashing (strips of lead tucked into brickwork or stone to make junctions watertight) and as a damp-proofing course to resist rising damp in brickwork. Other uses included decorative work, such as finials and weather vanes, and for the lead frames (lead cames) used in stained glass (pictured).

	= Building construction =		= Building construction =