What Is Design for Disassembly? How to Make Plastic Parts Easier to Recycle

What is design for disassembly? Design for disassembly means designing a product so it can be taken apart easily at the end of its life and its materials separated and recycled. For plastic parts, the most effective step is single-material simplification: using one plastic or compatible plastics, so the part can be recycled without being separated first.

Key points

• Design for disassembly makes products easier to repair, reuse and recycle at the end of their life.

• Using a single plastic or plastics from the same family is the simplest way to improve recyclability.

• Snap fits and standard screws are easier to separate than adhesives, welds and moulded-in metal inserts.

• Marking parts with their material code helps recyclers identify and sort them.

• EU ecodesign rules and UK right to repair rules are making disassembly a bigger consideration for product designers.

• These decisions are easiest and cheapest to make before the tool is built.

  
  

Most of a product's recyclability is decided at the design stage. Once a tool is made, changing materials or fixings becomes slow and costly. This guide sets out the main principles of design for disassembly for injection moulded parts and how to apply them without compromising performance or cost.

Why does design for disassembly matter?

When a product reaches the end of its life, recyclers need to separate it into clean streams of material. Mixed plastics, glued joints and hidden metal parts make that slow and expensive and many products end up in landfill or incineration as a result.

There are also commercial reasons to think about it now:

• Customer expectations. More businesses are asking suppliers about recyclability and supply chain emissions

• Regulation. The EU Ecodesign for Sustainable Products Regulation, which came into force in July 2024, will gradually set requirements for product groups covering durability, repairability, recyclability and information on dismantling. UK businesses selling into the EU will need to meet them.

• Right to repair. UK rules introduced in 2021 require spare parts to be available for some household appliances. Products that come apart easily are much simpler to repair.

• Lower costs. Fewer materials and simpler assembly often reduce production costs as well.

What is single-material simplification?

Single-material simplification means designing a product or a sub-assembly so that as many parts as possible are made from the same plastic. If a whole assembly is made from polypropylene, for example, it can go into a polypropylene recycling stream without needing to be taken apart.

Where one material cannot do every job, the next best option is to use plastics from the same family that can be recycled together. A polypropylene housing with a PP-based TPE soft-touch grip is one example.

Common combination	Recyclability	Better alternative
ABS housing with a PC window glued in place	Hard to separate, mixed stream	Snap-fit window or a single clear material if the design allows
PP housing with a TPU grip overmoulded	Different families, hard to separate	PP housing with a PP-based TPE grip
Nylon part with a moulded-in brass insert	Metal must be removed before recycling	Heat-set or press-fit insert that can be removed or a moulded-in thread where loads allow
Painted or chrome-plated plastic part	Coatings contaminate the recycled material	Moulded-in colour and texture
Assembly with paper or film labels	Label material and adhesive contaminate the stream	Moulded-in logos, text and markings

Which fixings make products easier to take apart?

How parts are joined has a big effect on how easily they can be separated.

• Snap fits. Moulded into the part, they need no extra materials. Designed with a release point, they can be undone with a simple tool.

• Standard screws. Easy to remove with common tools. Using the same screw size throughout speeds up disassembly.

• Clips and push-fit features. Quick to assemble and to separate.

• Adhesives and solvent bonding. Hard to separate and best avoided where disassembly matters.

• Ultrasonic and hot plate welding. Strong and clean, but permanent. Welding two parts of the same material is fine for recycling, though it prevents repair.

  
  

How should plastic parts be marked for recycling?

Recyclers sort plastics by type, so clear marking helps. ISO 11469 sets out how to mark plastic products with their material, using the abbreviations defined in ISO 1043. A polypropylene part would be marked >PP< and a glass-filled nylon part >PA6-GF30<.

Marking can be added to the tool, so it appears on every part at no extra cost per part. Place it on a surface that is not visible in use but easy to find once the product is taken apart.

What other design choices improve recyclability?

• Avoid unnecessary additives. Fillers, flame retardants and some pigments can limit recycling options. Use them only where the part needs them.

• Think about colour. Natural and light colours are easier to recycle into a wide range of new products. Our guide to pigmentation explains how colour is added during moulding.

• Use moulded-in finishes. Textures, colours and logos moulded into the part avoid paints, coatings and labels.

• Make fixings easy to find. Access points for screws and clips should be visible or clearly marked.

• Consider recycled content. Many parts can use recycled polymers, which supports a circular approach from the start. Our article on recycling in plastic manufacturing covers this in more detail.

  
  

Does designing for disassembly compromise performance?

Not usually, as long as it is considered early. In many cases it makes the design simpler, with fewer parts, fewer materials and fewer assembly steps. There are times when a second material or a permanent joint is the right choice for safety, strength or sealing and that is fine. The aim is to make sure every material and fixing is there for a clear reason.

It pays to review these points before the tool is made. Changing a material or adding a snap fit is a simple design change at the CAD stage and a costly tool modification later.

Frequently asked questions

What does single-material design mean?

It means making a product or assembly from one type of plastic or from compatible plastics in the same family, so it can be recycled without separating the parts first.

Are snap fits strong enough to replace screws?

For many applications, yes. Well-designed snap fits hold securely and can be released for disassembly. For high loads or parts that are opened often, screws may still be the better option.

Can existing products be redesigned for disassembly?

Often, yes. Simple changes such as replacing an adhesive joint with a snap fit or adding material markings can usually be made with a tool modification. Larger changes may need a new tool.

Does design for disassembly cost more?

It often costs less, because fewer materials and simpler assembly reduce production costs. Any extra design time is usually small compared with the cost of changing a tool later.

How do I know which plastics can be recycled together?

Plastics from the same family, such as polypropylene and PP-based elastomers, can often be recycled together. An experienced moulder or material supplier can advise on compatible combinations for your part.

How Amey Plastics can help

At Amey Plastics, our design team can review your part at the earliest stage, suggest material and fixing options and help you build recyclability into the design before the tool is made. With in-house design, prototyping and tooling, we can test ideas quickly and make changes without delay.

If you would like a design review for a new or existing part, our team would be happy to talk it through. Call us on 01730 266525 or email sales@ameyplasticsltd.co.uk.

About the author

Ken Scott, Managing Director

Ken began his engineering career at 15 with a City & Guilds apprenticeship in toolmaking, then worked as an in-house toolmaker for a plastics company before setting up his own business. He carries out the technical design work for Amey Plastics customers using 3D CAD, SLA modelling and 3D printing.

Last reviewed: October 2026. Next review: October 2027.