A collection of 19 chairs made by designers Tom and Will Butterfield over 19 days during Covid-19 lockdown will be customised by 19 leading designers and artists.

Initiated as "a celebration of one of the most humble pieces of furniture", the duo's 19 Chairs project saw them design and build 19 unique chairs from 27-by 27-millimetre square-section timber and 40-millimetre wood screws.

The chairs have purposely been left bare to serve as a "blank canvas" for the chosen 19 designers to customise.

With spare time on their hands due to the coronavirus lockdown restrictions, the brothers, who work in graphic design and product design, made each of the chairs by hand over 19 days from a workshop at the end of their garden.

"As the world adjusts to a new and improved way of living, 19 Chairs is a celebration of two things that won't change; creativity and the humble chair," Tom told Dezeen.

"When all seems damaged, 19 Chairs was born to make something good out of a global pandemic," he added. "Using our combined skills it has been important to respond to the current climate and find new ways to stay creative at home."

Having completed the first stage of the project, stage two will see them deliver the chairs to 19 different artists and designers to revamp for an older person to use.

The customised chairs will be sold to raise money for charities with 50 per cent of all profits going to Age UK and the other half will be donated to Resourcing Racial Justice.

"This gave our collaborators some initial structure and guidance without being too restrictive," said the duo. "It was important that there was scope for creative freedom to ensure 19 different outcomes."

Ten creatives have already signed up for the challenge, including British designer Tom Dixon, graphic artist Morag Myerscough, sculptor Wilfrid Wood, and artist Max Siedentopf.

Other names include hat designer Emma Brewin, artist Helmut Smits, James Shaw, Antony Williams, Henry Gorse and Harry Grundy.

"Tom and I had so much fun designing and making all 19 Chairs, we wanted to spread the project far and wide for other creatives to get involved and enjoy this unique time as much as we had, hence the launch of stage two," Will told Dezeen.

The brothers used 3D-modelling techniques to map out the design of each chair before crafting it, to ensure each one looked different. They ended up designing over 50 chairs before selecting 19 for production.

"Lockdown has meant that a lot of businesses have had to close, so it was important that we used easily sourced materials," Tom explained.

"Using 27 millimetre-square section timber and wood screws initially seemed restricting. However, the results prove that by using just the bare essentials it is possible to create a unified collection," he added.

"The making process was quite simple," Tom and Will continued. "Using a few basic materials and common tools all 19 chairs can be made by anyone, in any home."

Using a chop-saw, the designers would cut each length of wood ready for assembly. As they were using 27 millimetre-square section timber, they explained that every measurement had to be a multiple of 27, making it easy to locate where each piece fitted together.

"The most challenging part was having to learn my 27 times table! It was very much like assembling a 3D puzzle," said Tom.

The Butterfield brothers are still looking for nine more artists and designers to redesign the remaining chairs, and are encouraging any creatives interested in getting involved to contact them via email, which can be found on their website.

Other designers making the most of their time while in lockdown include Freyja Sewell, who created eight decorative face masks from commonplace objects found in her house, including yoghurt pots and a pool table triangle.