Designed for PBS International
By Tan Yong Kuan
light.painting.design@gmail.com
Vermicomposting bag
Executive summary
Harnessing the breathable and durable quality of the pollination bags, this new design optimises the
features of the material to make the environmentally-friendly practice of composting more convenient
for new or existing users. A growing issue with composting is the lack of space in homes, with large
bins (which are expensive) that do not fit in small apartments. The portable design of the bags and its
smaller size allows it to serve as an introductory device for users seeking to try out vermicomposting
at home without the necessity of investing in bulky equipment.
Context
The issue of food wastage is becoming more prominent in recent years, with campaigns from Tristram
Stuart and projects such as wastecooking that are actively highlighting the cause. Food waste is
mostly regarded as general waste to be incinerated or land-filled, and facilities that recycle food waste
are unable to cater fully to the existing output of food waste. One way an individual can do to combat
this problem, is to start vermicomposting their own food waste, such that less stress is placed on
conventional waste disposal methods, and their own food waste can be down-cycled into compost for
gardening purposes.
Vermicomposting, the breaking down of organic material with worms into high-nutrient compost, has
no odour, requires no turning and is faster than conventional composting when executed well. This
makes it suitable for the indoor environment with space constraints.
Product
Designed for PBS International
By Tan Yong Kuan
light.painting.design@gmail.com
The bag will serve as a vermicomposting bag, which is naturally ventilated due to its breathable
material. The bag is flexible enough to be folded, and features a cap that allows easy removal of ready
vermicast. A plastic base is included to hold the bag in place and collect any ‘compost tea’ produced
in the vermicomposting process.
Features:

Small ‘footprint’ – The bag takes up less space compared to those available currently, making
it more suitable for smaller living areas. The expandable and compressible feature of the bag
makes space-saving possible when the bag is not fully utilised.

Design for easy collection – Bottle cap and flexible bag design allow users to extract the
ready compost easily without having to sift through content to pick out worms.

Freedom of customisation – The bag can be printed or decorated with markers to look more
aesthetically-pleasing, or for record purposes.
The bag will come along with an recycled plastic base to hold the bag up and collect any ‘compost tea’
liquid that seeps out of the bag.
Materials:
For each vermicomposting bag, the following materials are used:
1. 3 used pollination bags
2. 1 used 2-litre milk bottle (for the bottle cap section)
3. Tin tie (larger version of those used in tin tie bags)
4. Recycled plastic resin (for production of plastic base)
Method of production
Designed for PBS International
By Tan Yong Kuan
light.painting.design@gmail.com
Designed for PBS International
By Tan Yong Kuan
light.painting.design@gmail.com
Designed for PBS International
By Tan Yong Kuan
light.painting.design@gmail.com
Designed for PBS International
By Tan Yong Kuan
light.painting.design@gmail.com
Production processes and analysis
Bag:

Duraweld technology and adhesives will be required to join the sheets from 3 used bags to
form a vermicomposting bag.

Although the cutting can be mechanised, labour will be required to ensure quality control.

Printing of bag designs can be done using screen printing or transfer printing, though nontoxic and waterproof inks are optimal given the nature of the bag’s purpose.
Cap

Sourced from recycled plastic milk bottles, labour will be required to remove the wanted
section from the bottles.

There might be a need to standardise caps, and as such there will be reliance on a particular
brand of milk bottles.

The cap can also be specially produced for the bag, however given the cheaper cost and
environmental-friendliness of reusing products, collecting used bottles and extracting the
necessary component might be better.
Plastic base

If produced in large scale, injection moulding will be cheaper per unit cost despite the larger
initial tooling cost.

Existing product alternatives can be sourced instead of producing the base. However, size
compatibility issues and the need to maintain the aesthetic look will make the task too
difficult to be cost-effective.
Production economics
Time taken to produce one unit manually (excluding plastic base): 1 hour
Designed for PBS International
By Tan Yong Kuan
light.painting.design@gmail.com
In order to make this product cheaper in cost, it will have to be manufactured in a large quantity
(exceeding 1000 units) in order to maximise economies of scale.
Estimated production costs (per bag + base):
Labour
£1
Durawelding
technology
and
adhesive £2
application
Plastic base production (assuming injection £4
moulding is used for high quantity production)
Collection of used bags and bottles and treatment
£2
Design royalties & printing (for premium range)
£2 (optional)
Subtotal: £12
Suggested retail price - £29.90
Average lower retail price for plastic worm bins - £40
The lower production cost due to the use of reused materials and cheaper production methods allow
for a lower retail price, which makes it more attractive for new users to vermicomposting to try it out.
If printing is used for the bags to decorate it with colourful motifs and designs, the bags can be priced
at a small premium.
Alternative production
Given the possible production of the bags in small scale, if a small scale production is preferred over
large scale production, the exclusion of the recycled plastics base is possible as its production will
require economies of scale to make it profitable.
SWOT analysis
Strengths
Weakness

Lower production cost


Novel design in comparison to existing
Niche market for vermicomposting
Designed for PBS International
By Tan Yong Kuan
light.painting.design@gmail.com
products

Related to company core business
Opportunities

Design allows customisation of size and
aesthetic look.
Threats

Easy replication of design by competitors