FAQs

1 - Why does Abbey use Code Colour references and not Code Numbers…?
2 - What is metric BSEN 12588:2006?
3 - What is Code Yellow?
4 - Can I use metric as I do imperial?
5 - What’s is the effect of using Metric references instead of old imperials reference numbers?
6 - What is a Barmark?
7 - What guarantee do you offer on your lead rolls and sheet?
8 -  What is The Complete Range?

 

1 - Why does Abbey use Code Colour references and not Code Numbers…?

Not a short answer, but it is a simple answer; the heavier imperial references such as Code 3, Code 4, Code 5 etc, that you [contractors, architects and specifiers, insurers, merchants and other UK manufacturers] use, do not appear within the British National Standard BSEN12588:2006; and have not done for a long time.

Essentially, Code 4 as a description, does not exist as a refence within the standard; the correct description as used by Abbey Metals is Code Blue.

Furthermore, related Metric British National Standards such as BS6915 and BS5534, also incorrectly reference the old imperial number codes. As do other UK manufacturers, training bodies and their related industry associations and insurers’.

Abbey Metals has chosen to unify the descriptions that we use across the whole of our business by using the correct Colour Code references. In doing so, this allows us to introduce a greater range of products to the UK market – such as Code Yellow [not covered by the imperial lb/ft2 numbering system].

A key driver to this decision came about as we chased sustainability across our business. We recognised that the continued use of imperial references, all of which relate to the thickest material of any Colour Code [e.g. Code Red range 2.00mm to 2.24mm, when Code 5 only refers to 2.24mm], restricted our ability to change. It was also immediately apparent that, to use the old imperial codes, may, in many circumstances, result in overspecification of product and the potential for additional end-user costs.

2 - What is metric BSEN 12588:2006?

BSEN 12588:2006 covers the manufacture of Rolled Lead Sheet for building purposes, is a metric standard that uses Colour Code references for Lead Sheet between 1.25 mm up to 6.00 mm. Abbey Metals uses the exact same Colour Codes as set out within the standard.

BSEN 12588:2006 is a metric standard which determines the thickness of lead, used in practice, and expressed in millimetres [mm]. Each thickness range is identified by its Colour Code. E.g. Code Red offers a range between 2.00 and 2.24mm. Within the Code red range, any thickness is available [e.g. 2.10mm], however, in practice, either 2.00mm or 2.24mm are typically specified.

Note: The standard does not contain imperial number references E.g. Code 4 – added here for your reference.

BSEN12588:2006 Colour Codes	Nominal thickness (mm)
Green	1.25mm	to	1.32mm [code 3]
Yellow	1.50mm	to	1.59mm [yellow]
Blue	1.75mm	to	1.80mm [code 4]
Red	2.00mm	to	2.24mm [code 5]
Black	2.50mm	to	2.65mm [code 6]
White	3.00mm	to	3.15mm [code 7]
Orange	3.50mm	to	3.55mm [code 8]
The thickness given are used in practice. >3.55mm designated by thickness reference only.

Note: Related Metric British National Standards; BS 6915 and BS 5534 both still incorrectly reference the heavier, old imperial number codes. The use of which, limit the specification of otherwise suitable product and may result in overspecification.

3 - What is Code Yellow?

Set out within BSEN 12588:2006, Code Yellow [1.50mm] conveniently falls between old imperial Code 3 [1.32mm] and Code 4 [1.80mm] and is used for the same flashing applications. Code Yellow is typically chosen as a cost-effective alternative to using Code 4 without compromising on longevity whilst still achieving industry guarantees and warranties when installed to BS6915 and BS5534.

As with all Colour Codes, there are constraints, which include maximum install lengths of 1.50 metres and the lead element area is not to exceed 0.35 m2. E.g. A traditional 9” flashing; 1.50m x 225mm [9”] = 0.34m2.

Flashing applications include [not exclusively]: abutment, step flashings and soakers, chimney flashings, gutters and back aprons, lead slates, cover flashings and damp-proof course. Code Yellow can be welded.

4 - Can I use metric as I do imperial?

The following link will take you to a table of guidance that will point towards which product will be used and for which application. Note that it is for the installer to determine a products suitability dependent upon the building constraints, geographical location and exposure to the elements.

Follow this link to view the table [link here]

5 - What’s is the effect of using Metric references instead of old imperials reference numbers?

Simply put, none whatsoever – the thickness of the Rolled Sheet deemed necessary yesterday, will still be necessary today.

However, the increased metric thickness range does provide you with more choice when choosing a lead product that suites the individual nature of your project or home.

In the real World:

Historically to be found in many UK lead manual publication, the statement, “Lead is more than likely to outlive the building to which it is applied”; is now less relevant as a result of modern manufacturing technologies and the change to modern building practices.

Change of building use, refurbishment, building design trends and the lower life expectancy of surrounding substrates means that most lead used in modern buildings today will be stripped off way before the life expectancy of the lead product comes into questions.

Does my flashing need to last 300 years?

Does my loft conversion or new build home require a lead flashing that will ‘outlive the building’, outlive all insurances and all of the other products around it. Or is it better that a lead product, with all its attributes, is chosen that best suites the build, ‘its current use’, and your purse.

Final consideration

Other considerations with regards to the thickness of lead sheet comes down to changing working practices. In the 1970’s, ‘bossing’ (the act of shaping malleable lead metal, with bossing tools to fit a surface) represented up to 70% of the install. Today, this is said to be less than 20%. This change in working practice, especially when considering Flashing installations, means that welding is now more commonplace and therefore, and thinner lead sheet can be used.

6 - What is a Barmark?

 As we manufacture from flat plat and not heavy coiled lead bobbins, Abbey Metals does not suffer from Barmarks. That’s being said, they are prevalent within the industry and so an explanation of what they are may be of assistance.

A Barmark refers to a series of perpendicular linear indentations that can appear along the full length of a lead roll. These marks are spaced in alignment with the roll’s circumference, with the intervals between them narrowing as they approach the roll’s centre.

Industry Oversight & Contractor Frustration:

Despite consistent feedback from contractors, the issue of Barmarks has been largely overlooked by manufacturers and their affiliated associations. Some producers claim to operate “Barmark-free” mills - an implicit acknowledgment of the problem. Yet, according to respected industry artisans, these mills reportedly produce lead of no better quality than standard operations. 

Do Barmarks Affect Performance?

Functionally, Barmarks are unlikely to compromise the performance of the lead sheet. However, from an aesthetic standpoint—especially when laid in bays—they can detract significantly from the visual finish of a roof. In some cases, the marks are so pronounced they remain visible from ground level, undermining the overall presentation.

Can Barmarks be removed? 

Realistically, removal is extremely difficult. Historically, lighter codes allowed for “flapping out” the mark—using a strip of lead to repeatedly strike the affected area. For heavier codes, the only viable method was heating and dressing the sheet. Both techniques are labour-intensive, slow, and no longer considered acceptable in modern practice.

Speak to us if you wish to order Barmark FREE lead.

7 - What guarantee do you offer on your lead rolls and sheet?

Abbey Metals offers a 50-year guarantee on its Rolled Sheet Lead, manufactured to BSEN 12588:2006 making them a reliable choice for various construction and heritage projects.

View full detail of our guarantee [link here]

8 -  What is The Complete Range?

The Complete Range refers to ALL Rolled Lead Sheet products, produced for building purposes, manufactured to BSEN 12588:2006; range from 1.25 mm up to 6.00 mm. The complete range as defined within 12588 offers more products and installation options than previously available for purchase within the UK.

British Standard 12588 is a metric standard as is the British National Standard, BS 6915 and BS5534 (although 6915 and 5534 continue to contain references to imperial sizes).

Note: 12588 does not contain imperial number references E.g. Code 4 – added here for your reference. 

BSEN12588:2006 Colour Codes	Nominal thickness (mm)
Green	1.25mm	to	1.32mm [code 3]
Yellow	1.50mm	to	1.59mm [yellow]
Blue	1.75mm	to	1.80mm [code 4]
Red	2.00mm	to	2.24mm [code 5]
Black	2.50mm	to	2.65mm [code 6]
White	3.00mm	to	3.15mm [code 7]
Orange	3.50mm	to	3.55mm [code 8]
The thickness given are used in practice. >3.55mm designated by thickness reference only.