This question pops up a lot, especially among those diving into natural building for the first time. The short answer? Yes, plasterboard can absolutely be both natural and breathable—but like most building materials, context is everything.
If you’d rather hear Andy and Chris talk through the ideas in this article, you can watch Episode 1 of Can I Just Ask? below. 👇
The Case for Plasterboard
Plasterboard (often called drywall in the US) is made primarily from gypsum, a naturally occurring mineral that’s mined, crushed, and then heated to remove moisture. It’s then sandwiched between layers of recycled paper to form boards. So in terms of its raw ingredients, plasterboard ticks the “natural” box quite comfortably.
What surprises many is just how useful and versatile it is within a natural building context. Gypsum is vapour permeable—in other words, breathable. In fact, its ability to buffer moisture in internal spaces compares favourably to materials like lime, which is traditionally heralded as the go-to for breathability.
Plasterboard also carries significant practical advantages. It’s fire-resistant, widely tested, easily sourced, and familiar to most contractors. That makes it a rare gem in the world of sustainable materials: accessible, high-performance, and non-niche.
Performance Depends on Context
So why do some people report plasterboard ‘failing’ in their homes—crumbling, blistering, or becoming damp? More often than not, it’s a case of the wrong material in the wrong place. Gypsum plaster, for instance, shouldn’t be applied directly to bare masonry, especially in cold, uninsulated buildings. Masonry walls can be cold and moisture-prone, and gypsum is hygroscopic (meaning it readily absorbs water). That can create a soggy mess if you’re not careful.
But paired with a proper insulation system—like a wood fibre board that regulates temperature and moisture—plasterboard becomes a robust, breathable internal finish. In these setups, the gypsum layer sits on the warm side of the wall, well away from condensation risks. It’s not just functional; it can enhance the overall performance of the building fabric.
The Landfill Problem—and the Fix
Of course, no material is perfect. One major sticking point for plasterboard’s reputation in natural building circles is its behaviour in landfill. When gypsum breaks down in the presence of organic waste, it can release hydrogen sulphide—a toxic gas.
But this is less a flaw in the material and more a problem with how we handle waste. Gypsum is actually infinitely recyclable if the infrastructure is there. It can even be reprocessed into new boards or alternative products like Fermacell, a promising innovation in low-carbon building.
A Word on Embodied Energy
Another tick in plasterboard’s favour is its low embodied energy. Unlike lime, which requires intense heat to process (burning limestone at over 1000°C), gypsum is fired at a much lower temperature—around 150°C, roughly equivalent to a domestic oven. That translates into less energy use, lower emissions, and reduced cost.
So, Should You Use It?
If you’re working on a natural, breathable build and need a fire-rated, easy-to-install, and vapour-open wall lining, plasterboard deserves serious consideration. As ever, the key is to understand the whole system: where it’s going, what it’s fixed to, and how it interacts with moisture and temperature.
Read the datasheet. That’s where the truth usually lies. And when used in the right context, gypsum plasterboard isn’t just acceptable—it’s an unsung hero of natural construction.