3mm Aluminium Sloping Coping – 135° External Corner | 100mm External Leg

This 3mm aluminium coping corner is designed to create a clean 135° external corner detail on sloping aluminium coping systems. It is suitable for parapet walls, flat roof edges, roofline transitions, balconies, terraces and architectural building details where two coping runs meet at an external angle.

Made from 3mm aluminium, this coping corner provides a durable, lightweight and low-maintenance finish for UK residential and commercial projects. The 100mm external leg helps create a neat visible edge, while the sloping profile supports rainwater run-off from exposed wall tops. It can be used with matching aluminium copings and other roofline products to create a consistent finish across the project.

This product is available in size options from 510mm to 1060mm, with RAL colour selection available before ordering.

Key Benefits

• Creates a neat 135° external corner for sloping aluminium coping systems.

• Made from 3mm aluminium for a strong, lightweight and durable roofline detail.

• 100mm external leg helps provide a clean visible edge on parapet walls and roof edges.

• Sloping design supports water run-off from exposed wall tops.

• RAL colour options help match the coping with fascia, soffits, rainwater goods, cladding or other aluminium details.

• Suitable for UK residential, commercial, refurbishment and new-build projects.

• Custom-fabricated to your selected size and finish for a more project-specific result.

Product Details and Specification

Where This Product Is Commonly Used

This aluminium coping corner is commonly used by roofers, contractors, builders, architects and homeowners working on flat roof edges, parapet walls, terraces, extensions and commercial roofline projects. It is especially useful where two runs of aluminium sloping coping meet at a 135° external angle and need a clean, consistent corner finish.

For larger projects, this product can be used with straight coping lengths, stop ends, fixings and related aluminium roofline items. If the project also includes guttering or drainage upgrades, the finish can be coordinated with matching rainwater goods.

Why Aluminium Is a Good Choice

Aluminium is a practical material for external coping systems because it is lightweight, corrosion resistant and suitable for exposed roofline areas. It is easier to handle on site than heavier materials, which can help installers work more efficiently during roofline and parapet detailing.

The Council for Aluminium in Building explains that aluminium is lightweight, strong, long-lasting, highly corrosion resistant and recyclable, making it a strong choice for construction products. You can read more about the material here: benefits of aluminium.

For UK buildings, aluminium is particularly useful because it performs well in wet and changing weather conditions. It does not rust like some ferrous metals, and when finished correctly, it provides a clean architectural appearance with low ongoing maintenance.

Finish and Colour Options

This product includes a RAL colour selection option, allowing the coping corner to match or coordinate with the wider building design. A consistent colour choice can help the coping work neatly with fascia and soffits, cladding, downpipes, gutters, flashings, trims and other aluminium roofline details.

You can use the official RAL colour information as a general reference before selecting a finish. Screen colours can vary, so it is always sensible to confirm the required colour carefully before ordering, especially for projects where colour matching is important.

Installation and Ordering Notes

Before ordering this 135° external coping corner, measure the wall width, coping run and corner angle carefully. The selected size needs to work with the straight coping lengths on both sides of the corner, so check the full roofline detail before placing the order.

You may also need to consider fixings, joints, sealant, stop ends, external corners, internal corners, outlets and any adjoining roof coverings. If the project includes a wider roof drainage design, it may also be useful to review UK guidance such as Approved Document H: drainage and waste disposal.

This is a custom-fabricated item made to the selected size and finish. Please check all measurements and colour details carefully before ordering. If you are unsure about sizing, finish, compatibility or matching components, contact Online Metal Store Ltd before placing your order.

Why Buy From Online Metal Store Ltd

Online Metal Store Ltd supplies aluminium architectural products for UK roofline, rainwater and construction projects. The product range includes aluminium copings, rainwater goods, fascia and soffits, trims, flashings and related aluminium building products.

The company supports buyers with product dimensions, RAL colour selection, custom fabrication and order guidance. This is helpful for contractors, builders and homeowners who need the right size, finish and product type before ordering for a live project.

FAQ Section

What is this aluminium coping corner used for?

This product is used to form a 135° external corner on a sloping aluminium coping system. It is commonly used on parapet walls, roof edges, terraces and flat roof upstands.

What size options are available?

The product is available in size options from 510mm to 1060mm. Choose the size that matches your wall width and coping system.

Can I choose a RAL colour?

Yes. A RAL colour option is available before ordering. This can help you match the coping corner with fascia, soffits, gutters, downpipes, cladding or other aluminium details.

Is this product suitable for UK weather?

Yes. Aluminium is a practical choice for UK roofline products because it is lightweight, corrosion resistant and low maintenance when installed correctly.

Does the sloping profile help with drainage?

Yes. The sloping profile helps direct rainwater away from the top of the wall and supports better water run-off as part of a suitable coping system.

Is this item returnable?

This is a custom-fabricated item made to your selected size and finish. It is non-returnable unless faulty, so measurements and colour choices should be checked carefully before ordering.

What should I check before buying?

Check the wall width, corner angle, selected size, RAL colour, matching straight coping lengths, fixings, joints, stop ends and any wider drainage or roofline requirements.

Choose the required size and RAL colour before ordering. If you are unsure about measurements, finish options or matching components, contact Online Metal Store Ltd for guidance before placing your order.