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Heated Tables

Modify the Japanese Kotatsu, an economical way to keep warm and cozy in cold months

Photo of Ellie Henderson
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Common in Japan, almost every household has a Kotatsu or heated table. It is known as an economical way to keep warm. Usually the Kotatsu table is used indoors, but has been known to be modified for outdoor use. In this way, we have a model for which to work off. As anyone who has ever experienced this will attest, it is an unforgettable way to stay warm and cozy in the cold months.

Idea Title

Hygge Dining

Company / organization name (if applicable)


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A kotatsu typically consists of an electric heater attached to the under-side of a table. A blanket is draped over the frame and another flat surface placed on top. The double table top protects the blanket from catching fire. There are specific heaters designed to heat the table and these have grills which protect from burns. The level of heat can be adjusted to suit the user.

Solution Overview

The solution of having heated tables allows patrons to be safe and stay comfortably warm while still patronizing their favorite restaurants. For businesses, the heated tables means the ability to continue using their outdoor decks, rooftops, patios and car parks that they may already have invested in, but with some achievable modifications. Servers and business owners will still maintin the safety practices that are already in place,as well as techology such as ordering through websites with the QR codes on tables. The need to maintain high hygiene levels would also remain in place.

Instead of being enclosed in a tent or closed structure, heated tables allows for air circulation through open-air dining. This has proved critical in reducing transmission of Covid. The city will also be able to continue with initiatives such as the closure of streets for outdoor dining which has been a lifeline for those businesses that have limited outdoor space.


Beyond the ideas phase, the prototypes sketched below would be tested in real life.

Variations would be explored:


• Coffee tables 

• Regular sized tables

• Booths 

• Other seating that restaurants and bars may have

Ways to generate heat:

• Specific Kotatsu heaters

• No heating element, just body heat

• Other heating methods, ie heated mats.

Volunteers would gauge the level of comfort in different scenarios. These findings would guide a set of recommendations.

A website would be created providing resources eg videos showing how to modify existing tables safely, instruction kits. Another idea would be to put a call out for handy volunteers who are able to assist business owners in modifying furniture.

The cost for this solution would be low as it uses existing hardware. In terms of ongoing utility costs, it would be more economical than options such as heat lamps as the heat is trapped in a confined space.

Technical Overview

The tables are widely available for purchase in Japan, and there are numerous videos online explaining how to modify existing tables

1. Table/Tabletop

2. Heating element. Specific elements can be purchased online, that protect against any burns with a grill. These are better than space heaters. 

3. Basic L braces and screws fix element to the underside of the table.

4. A warm blanket large enough drop to the floor, trapping heat. 


5. Seating. Pillows, lawn chairs if sitting Japanese-style. Regular chairs may need a flap added to the front to prevent heat from escaping.

6. Flooring if sitting Japanese-style. ie Synthetic grass, foam mats, outdoor rugs, decking.


Consideration would need to be made for those who have special needs. Wheelchairs could be situated at regular height tables with blanket draped over. There would also be a consideration for a shift in cultural expectations . In some cultures it is usual to sit on the floor while eating, ie Japan, China, India, Pakistan, while in Western Cultures, not so much so. However, this could offer a new and intriguing dining experience.


As part of the prototyping process, we would need to look at different dining situations and how best to adapt what restaurants and bars already have in terms of tables and seating. These sketches give consideration to how this would work in various situations.

User Research

This idea is inspired by my own experience of living in Japan. If idea is chosen, further user research could be conducted by volunteers in a temperature controlled environment to gauge the level of comfort. Consulting with restaurants and bars to discover their range of needs would also be achievable.

The ideas could also be extended to other situations, once people's behavior has been adjusted to adopt this new way of eating. As with new behaviours such as mask-wearing and social distancing, the benefits of still being able to socialize and support local businesses should drive change.

Covid-19 Safety

All of the current safety measures would remain in place, such as social distancing, mask-wearing and signage. Utilizing technology, such as ordering through websites with the QR codes on tables could be continued. The need to maintain high hygiene levels would also remain in place. 

Instead of being enclosed in a tent or closed structure, heated tables allow for air circulation through open-air dining. This has proved critical in reducing transmission of Covid.

There would also be a public-awareness campaign to encourage the public to dress warm, when dining out, as well as keeping up with existing precautions. There could be the option for patrons to bring their own blankets in some situations, if they feel more comfortable.

Tell us about yourself and your team. What is your background and experience?

I'm a Graphic Designer with experience in designing three dimensional spaces, mainly for trade shows and environmental branding. As an avid foodie, I would like to support my local restaurants that are struggling. They are the heart and soul of our communities and create the spaces where so many of our memories are made.

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In what city are you / your team located?


In what country are you / your team located?

United States

How did you hear about the Challenge?

  • In the news


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