The Aggregate- Podcast interview.

Plaster Man: Jethro Marsh on Craft, Conservation & a Life in Plaster

The story behind The Natural Plaster Company — from growing up around building conservation and finding a way into plastering, to traditional lime work, craftsmanship, social media and passing specialist skills on to the next generation.

I recently joined The Aggregate podcast from New Age Artisans for a conversation about plastering, conservation and the slightly unexpected route that led me to where I am today.

It turned into a wide-ranging chat covering everything from growing up around historic building conservation and learning the plastering trade to setting up The Natural Plaster Company, working with traditional materials and what the future might hold for lime plaster.

[LISTEN TO THE PODCAST – SPOTIFY EMBED]

Growing Up Around Conservation

Traditional buildings and conservation were around me long before I became a plasterer.

My father worked as a building conservator, and the house we grew up in seemed to be a permanent building site. His work was concerned with conserving the historic fabric of buildings and monuments — preserving what remained and preventing further deterioration rather than simply replacing old material with new. 

One of the major projects he worked on was the conservation of the west front of Wells Cathedral. During the 1970s the cathedral underwent an extensive period of conservation and research, including work to protect the hundreds of medieval sandstone sculptures covering its west front. It was also part of a wider period of renewed interest and research into lime and traditional conservation techniques. 

As a child, however, I didn’t particularly appreciate any of it!

Being surrounded by old buildings, lime and conservation certainly didn’t mean I had any intention of following the same path.

That came much later.

Finding My Way Into Plastering

My route into the trade wasn’t particularly planned.

I initially went in a different creative direction as a sign writer before finding my way into plastering. What appealed to me was the combination of practical, physical work and the opportunity to create something.

Over time, that interest moved increasingly towards the more traditional and specialist areas of the trade.

Decorative work, mouldings, natural materials, lime plaster and the repair of historic buildings offered something that ordinary plastering couldn’t.

There is an enormous amount of skill hidden within traditional plasterwork.

Sometimes the job is simply to repair what is already there. Other times it involves taking an existing profile, reproducing it, making moulds and casting replacement elements.

And occasionally there is an opportunity to create something completely new.

One project discussed in the podcast involved creating a series of decorative panels representing the four seasons. The work began with freehand clay modelling of classical decoration and acanthus leaves before moulds were made and the finished pieces cast for installation. 

It’s that mixture of craft, problem solving and creativity that has kept the trade interesting.

The Natural Plaster Company

Eventually the work brought me back towards Cornwall.

Much of the specialist decorative work I had been involved with was centred around London, but continually travelling and working away wasn’t something I could see being sustainable long term.

Cornwall presented a different opportunity.

We have an extraordinary stock of historic buildings and consequently a continuing need for traditional lime work, conservation and repair.

A workshop also allowed us to concentrate on running cornices and mouldings alongside site-based plastering and restoration work.

That gradually developed into The Natural Plaster Company.

Interestingly, the company didn’t start exactly where it is today.

Some of my earlier specialist work involved polished natural finishes and Tadelakt. The Natural Plaster Company logo actually originated from the circular motion of the stone used to burnish Tadelakt — something that has remained with the company even as the business itself has evolved increasingly towards heritage plastering, lime and traditional materials. 

Today, much of our work involves the repair and conservation of existing buildings rather than creating elaborate new decorative architecture.

After more than a decade, a large proportion of that work comes through reputation and relationships built with architects, surveyors and specifiers. 

But another form of word of mouth has become increasingly important.

Traditional Craft in a Digital World

Social media was something I came to relatively late.

I’d used LinkedIn for years to show photographs of projects, but I was initially fairly sceptical about Instagram and short-form video.

Eventually I started filming some of the work we were already doing.

And people watched.

There is something strangely compelling about traditional craft when you can actually see the process taking place.

Running a moulding, casting plasterwork, applying lime or making something by hand may be completely normal to someone working in the trade, but to somebody who has never seen it before, it’s fascinating.

The result has been an audience far beyond the people we would ever encounter through traditional construction industry networks.

As we discuss in the podcast, social media has effectively become a new form of word of mouth, and increasingly somewhere people actively search for trades, techniques and information. 

For traditional trades, that presents an interesting opportunity. Skills that might once have remained largely invisible outside a workshop or building site can now be seen by people around the world.

Passing Traditional Skills On

Perhaps the bigger question is what happens to those skills next. Finding people with the right specialist plastering skills isn’t always easy, particularly in Cornwall.

Historically, the Cornish Mason encompassed several of the wet trades rather than plastering necessarily existing as a completely separate discipline. Dedicated plastering courses have become more common, but many of the traditional techniques still have to be learned through experience. 

For us, taking on an apprentice and training him within the business has been a real success. It’s something I’d like to do again. Because preserving traditional materials isn’t enough on its own.

You also need people who understand how to use them.

What Is the Future of Lime Plaster?

Towards the end of the conversation, we get onto the future of lime plasters and mortars.

It’s an interesting question because traditional materials don’t necessarily have to remain frozen in the past.

One of the areas I think will become increasingly important is the relationship between lime, insulation and recycled materials.

There is already considerable interest in alternative aggregates and ways of combining the properties of traditional breathable materials with the thermal performance expected from modern buildings. 

That presents an interesting future for lime.

The fundamental material may be ancient, but the way we use it can continue to evolve.

And perhaps that is what conservation and traditional craft are really about.

Not simply recreating the past, but understanding the materials and skills well enough to carry them forward.

Listen to the Full Conversation

There’s much more in the full episode, including the realities of running a specialist plastering business, decorative plasterwork, mould making, social media, apprenticeships, family life and the wider international community of people keeping traditional plastering skills alive.

[LISTEN TO THE AGGREGATE PODCAST]

Explore Traditional Plastering

If you’d like to learn more about the materials and techniques discussed in the podcast, explore our guides, traditional lime plasters and specialist plastering tools.

→ Complete Guide to Traditional Lime Plaster
→ Shop Traditional Lime Plasters
→ Plastering Tools & Accessories
→ About The Natural Plaster Company