2mm Aluminium Flat Coping – Closed Stopend | 75mm External Leg
2mm Aluminium Flat Coping – Closed Stopend | 75mm External Leg
The corner pieces get the attention, but the stopend is just as critical to a weathertight parapet. A flat coping run has to terminate somewhere, whether that is at a wall end, at a junction with a building face, or at the transition between a coping run and a different building element. Leave that end open and you have a channel that collects water, feeds it back under the coping, and directs it straight into the wall construction below. It is one of those details that gets missed in a hurry and then causes a damp problem that takes months to track down.
This 2mm aluminium flat coping closed stopend caps the end of a 2mm flat coping run with a pre-formed, weathertight closure. It is available in 29 sizes from 185mm to 885mm to match virtually any parapet wall width, and it is powder coated in any RAL colour to match the rest of the coping system. Manufactured in Chelmsford, Essex, it is the final component that makes a flat coping installation complete.
Product Overview
The closed stopend is the terminal component for a flat coping run. Once the straight lengths are fixed along the parapet and the corners are in place, the stopend caps each open end of the run and seals it against water entry. The "closed" designation means the end face is fully sealed: the profile wraps over the top of the wall and closes off the open end of the coping entirely, with no gap for water to enter. This distinguishes it from the stopend upstand, which has an upstand that allows water drainage at the end of the run rather than a sealed closure. For most flat coping runs on a flat roof parapet, the closed stopend is the correct terminal piece at both ends of each run unless drainage off the end of the coping is specifically required.
This stopend is part of the Online Metal Store Ltd 2mm aluminium flat coping range with a 75mm external leg. It is fabricated to order in the size you select, with 29 sizes available to cover wall widths from approximately 15mm up to around 715mm depending on how the coping is detailed. All sizes are powder coated using an external grade polyester finish in any RAL colour, matching the flat coping lengths, 90 degree corners, 135 degree corners and brackets ordered for the same project.
Key Benefits
Fully Sealed End Detail
The closed design seals the open end of the coping profile completely. The end face, the top surface and the external leg are all formed from a single fabricated piece with no open seams at the terminal point. Once fitted and sealed with sealant at the joint to the straight length, the end of the coping run is as weathertight as the rest of the system. There is no exposed edge, no gap at the end cap, and no path for wind-driven rain to enter the wall at the coping termination.
29 Sizes to Match Any Wall Width
Available in 29 sizes from 185mm to 885mm in 25mm increments, this stopend covers virtually every parapet wall width you are likely to encounter on a UK flat roof project. The size you order should match the overall width of the flat coping profile on your parapet. That is the wall width plus the external legs on both sides plus the returns. The size guide below explains how to calculate this for your project.
Exact Colour Match Across the Full System
Because this stopend is ordered alongside the rest of the coping system and fabricated in the same batch, the powder coat finish will be an exact match to the lengths, corners and brackets in the same order. On a visible parapet, a stopend in a slightly different shade or sheen from the rest of the coping stands out. Ordering everything together from the same manufacturer in Chelmsford eliminates that risk completely.
Powder Coated, Not Anodised
All products in the 2mm flat coping range, including this stopend, are finished with an external grade polyester powder coating. This is the correct and accurate description of the finish process. Powder coating bonds a durable, coloured coating directly to the prepared aluminium surface and is available in any RAL colour. It is a different process from anodising and provides a broader range of colour options with excellent durability in exposed external conditions.
Fabricated in Chelmsford, Essex
This stopend is a custom-fabricated item made to your selected size at the Online Metal Store Ltd facility in Chelmsford. Because it is made in the UK to order, lead times are short and the size range is not limited to a handful of stock profiles. If your wall width falls between standard sizes, pick the next size up and discuss the detail with Online Metal Store Ltd. The UK manufacturing base means fast turnaround for projects across Essex, the South East and the wider UK.
Technical Specifications
Material: 2mm grade aluminium
Profile: Flat coping closed stopend
External Leg: 75mm
Available Sizes: 185mm, 210mm, 235mm, 260mm, 285mm, 310mm, 335mm, 360mm, 385mm, 410mm, 435mm, 460mm, 485mm, 510mm, 535mm, 560mm, 585mm, 610mm, 635mm, 660mm, 685mm, 710mm, 735mm, 760mm, 785mm, 810mm, 835mm, 860mm, 885mm (29 sizes in 25mm increments)
Finish: Polyester powder coating, external grade
Colour: Any RAL colour to order
Type: Closed (fully sealed end face)
Compatible System: 2mm Aluminium Flat Coping range | 75mm External Leg
Fabrication: Made to order - non-returnable unless faulty
Country of Manufacture: United Kingdom (Chelmsford, Essex)
How to Measure for the Right Stopend Size
The stopend size should match the overall width of the flat coping profile on your parapet, not the wall width alone. Here is how to work out the correct size:
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Step 1: Measure the width of the parapet wall at the top, from the outside face to the inside face. This is your wall width.
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Step 2: Add the two external leg dimensions. For a 75mm external leg coping, both legs are 75mm. Add 75mm + 75mm = 150mm to the wall width.
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Step 3: Add the two returns. The flat coping profile includes a small return lip on each side, typically 10mm each side. Add 10mm + 10mm = 20mm.
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Step 4: The total is your overall coping girth: wall width + 150mm + 20mm = wall width + 170mm. For example, a 215mm wide wall gives a coping girth of 385mm. Select the 385mm stopend from the size list.
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Step 5: If your calculated girth falls between two available sizes, select the next size up. A stopend that is very slightly oversized can be trimmed on site; one that is undersized will not seat correctly on the coping profile.
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Tip: if you already have a straight coping length on site, measure its overall width across the top including both legs and both returns. That measurement is your stopend size.
Closed Stopend or Stopend Upstand: Which Do You Need?
Both products terminate the end of a flat coping run, but they do it differently. The closed stopend seals the end face completely. It is the right choice wherever the coping run ends at a wall termination, an abutment with a building face, or a parapet corner where the end of the run is simply closed off. The stopend upstand has an upstand at the end of the coping that allows water to drain up and over the end rather than being fully sealed. It is used where the coping run ends at a higher point and drainage off the end of the run is part of the design detail, or where a post or upstand element needs to pass through the coping termination.
For the majority of flat roof parapet installations, including domestic extensions, garages, commercial flat roofs and boundary walls, the closed stopend is the correct choice at both ends of every straight coping run. Use the upstand version only where the design specifically requires an open or drained end detail.
How to Fit a Flat Coping Closed Stopend
Fix the aluminium coping brackets along the full parapet run first, including a bracket positioned close to each end of the run to give the stopend solid bearing. The bracket at the end of the run should sit far enough back from the wall termination to allow the stopend to seat fully over the end of the final straight length without the bracket fouling the stopend profile.
Once the straight coping lengths are in position, offer the stopend up to the open end of the final length and check the fit. The stopend should slide over the end of the coping profile and sit flush with the outer face of the straight length. Apply a continuous bead of colour coded sealant around the inside face of the stopend before pressing it into its final position. The sealant bead seals the joint between the stopend and the straight length on all three sides of the profile. Do not skip this step: the sealant is the only thing preventing water from tracking back through the butt joint between the stopend and the coping run.
Once the stopend is seated and the sealant bead is in place, secure the assembly using colour coded fasteners in the matching RAL colour. Fix through the top of the coping where the bracket bears, keeping fixings in line with the bracket positions so they are supported. Apply a finishing bead of sealant to the external joint line where the stopend meets the straight length for a clean, weathertight termination.
Where the Flat Coping Closed Stopend Is Used
Domestic Flat Roof Extensions
Every flat roof extension with a parapet needs a stopend at each end of every coping run. On a standard rectangular rear extension, there are typically four straight runs and up to eight stopend positions depending on the layout. The 2mm flat coping system is the most common choice for domestic work across Essex, East London and the South East, and the closed stopend is the standard terminal piece for this application. Ordering the stopends at the same time as the lengths, corners and brackets ensures everything arrives colour-matched in a single delivery.
Flat-Roofed Garages and Outbuildings
Garages and outbuildings with flat roofs are a significant proportion of the domestic coping market. A detached or integral garage with a parapet wall on three or four sides will typically have four straight coping runs, each needing a closed stopend at both ends. On a garage or outbuilding where the coping is less visible from street level, the temptation is to skip the stopends or bodge the end detail. That is a mistake: water ingress at an open coping end causes damp in the wall below that can take years to manifest visibly and is expensive to fix.
Commercial and New-Build Parapets
Commercial flat roof parapets on office buildings, retail units and light industrial units across the South East commonly use aluminium flat coping as the parapet cap. On a commercial project, all system components are specified together, and the stopends are ordered as part of the full coping system from the same manufacturer. Housebuilders on NHBC-registered new-build developments will typically order the full system, including stopends, from the aluminium flat copings range, to ensure colour and profile consistency across all plots on a development.
Boundary Walls and Landscaping Features
Aluminium flat coping is increasingly used on low boundary walls, screen walls and raised planting beds where a clean, low-maintenance cap is required. On a boundary wall with a defined end, the closed stopend provides the neat sealed termination that makes the wall look finished rather than simply cut off. It works alongside the 90 degree corner and 135 degree corner to complete the full perimeter coping on a landscaping structure where multiple directions and terminations are required.
Frequently Asked Questions
What does a flat coping stopend actually do?
It seals the open end of a flat coping run. When a flat coping system is installed along a parapet wall, the straight lengths leave an open profile at each end of the run. Without a stopend, that open end is a gap where wind-driven rain can enter the coping profile and track back into the wall or the flat roof build-up below. The closed stopend caps that end completely, creating a sealed termination that is weathertight on all sides. It is fitted at both ends of every open coping run as the final component in the system.
How do I work out what size stopend I need?
Measure the overall width of the flat coping profile you are using, which is the wall width plus both external legs plus both returns. For a 75mm external leg flat coping, that is wall width plus 170mm (75mm + 75mm + 10mm + 10mm). A wall that is 215mm wide gives an overall coping girth of 385mm, so you would order the 385mm stopend. If your figure falls between two available sizes, order the next size up. The size range runs from 185mm to 885mm in 25mm steps, covering wall widths from approximately 15mm up to around 715mm.
What is the difference between a closed stopend and a stopend upstand?
A closed stopend seals the end of the coping run completely. The end face is formed as a solid closure with no opening. A stopend upstand has an upstand element at the end of the coping that allows water to drain up and over rather than being fully sealed in. The upstand version is used where drainage off the end of a coping run is required by the design, or where a structural element needs to pass through the coping termination. For most domestic and commercial flat roof parapet installations, the closed stopend is the correct choice. Use the upstand only where the design specifically calls for it.
Is this stopend powder coated or anodised?
It is powder coated. All products in the 2mm flat coping range, including this stopend, are finished with an external grade polyester powder coating. The powder coat is available in any RAL colour and provides excellent durability in UK external conditions. These products are not anodised. Anodising and powder coating are two different finishing processes: powder coating applies a coloured protective layer to the surface, while anodising is an electrochemical process that hardens the oxide layer on the aluminium. The finish on this product is powder coating only.
Can I return this stopend if I order the wrong size?
This is a custom-fabricated item made to your selected size and RAL colour. As with all made-to-order products, it is non-returnable unless it arrives faulty or materially different from what was ordered. This is why the size guide above is important: take the time to measure the overall coping girth correctly before placing the order. If you are unsure of the size you need, contact Online Metal Store Ltd before ordering and the team will help you confirm the correct size based on your wall width.
Part of a Complete Flat Coping System
This stopend is one component in the complete 2mm aluminium flat coping system with a 75mm external leg. A flat roof parapet needs lengths, corners, stopends and brackets from the same range to ensure consistent profiles, matching colours and a fully weathertight perimeter. The full 2mm flat coping system with 75mm external leg includes:
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2mm Aluminium Flat Coping 90 Degree Corner | 75mm External Leg
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2mm Aluminium Flat Coping 135 Degree Corner | 75mm External Leg
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2mm Aluminium Flat Coping - Closed Stopend | 75mm External Leg (this product)
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2mm Aluminium Flat Coping - Stopend Upstand | 75mm External Leg
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2mm Aluminium Flat Coping - 90 Degree T-Junction | 75mm External Leg
For the full range overview, visit the Aluminium Flat Copings collection page. If you are working with 3mm coping, the 3mm flat coping closed stopend is the correct terminal piece for the heavier gauge system.
Standards and Compliance
Flat roof parapet coping systems in the UK are detailed in accordance with BS 6229:2018 - Flat Roofs with Continuously Supported Flexible Waterproof Coverings. This standard covers parapet and edge detailing for flat roofs and includes requirements for coping system terminations. A properly fitted and sealed closed stopend at the end of each coping run is part of a complete and compliant parapet detail under this standard.
The powder coat finish on all Online Metal Store Ltd aluminium flat coping components, including this stopend, is applied in accordance with BS EN 12206-1 - Organic Coatings on Aluminium and Aluminium Alloys. This is the performance standard for external-grade powder coatings on aluminium. Every component in the range, from the lengths to the corners to the stopends, is coated to the same specification, which means the colour, gloss and durability characteristics are consistent across the full installed system.
For NHBC-registered new-build projects, Chapter 7.1 of the NHBC Standards sets out parapet wall and flat roof construction requirements. A fully detailed aluminium flat coping system with properly fitted stopends at every run termination is consistent with these requirements and supports the new-build warranty position.