Greenhouse BioDome
28m² greenhouse dome — under €300, one weekend, greenhouse plastic. Build Guide →
Turn Invasive Trees Into Fire-Resistant Homes
Open-source architecture for building with eucalyptus in Portugal.
The Problem
The Silent Invasion
Section titled “The Silent Invasion”I know at least three people who have lost their homes to fire season in this part of Portugal.
It never used to be this way, but invasives have a way of becoming permanent additions to an ecosystem, and we’ve got to learn how to live in harmony with them.
The problem with eucalyptus — or fire trees, as they’re known in their native Australia — is that they have no natural predators here. Their resinous tissue repels all but the cuddly koala, and we’ve got none of those around to make a dent. Across 26% of Portuguese forests, over 800,000 hectares have been conquered by Eucalyptus globulus. The ground beneath them is bare. Nothing grows. Where there should be cork oaks, stone pines, and strawberry trees humming with life, there is silence.
Every fire season leaves behind charred stone ruins of homes that used to be, homes that need rebuilding. And the rebuilding of a charred home can quickly bankrupt a family. Where are they going to stay during the multi-year process? Whole families stuck together in a cold camper trying to survive wet winters while they rebuild with expensive and toxic manmade materials.
Two Problems, One Dome
Section titled “Two Problems, One Dome”But there’s another predator afoot with an insatiable appetite that just needs to develop a taste for eucalyptus flesh. The widespread fires are in part responsible for this herbivore’s arrival — every fire season creates demand for rebuilding.
If only we could solve two problems with one dome. How do we unleash the insatiable predator of home construction against the very trees that are destroying our homes? And how do we selectively target their young so that they stop coming back?
The solution exists already in the heart of the problem.
We find a way to construct quick, easy, and cheap structures from young flexible eucalyptus poles — in a way that doesn’t resist the euc’s natural tendency to twist as it dries. Enter the Regenerative BioDome.
The Solution
What If Removal Created Value?
Section titled “What If Removal Created Value?”What if the act of removing invasive species produced something valuable? What if watershed healing could be economically viable? What if “waste” biomass became functional architecture?
1
Heal the Land
Remove 50-200 invasive trees, returning thousands of liters of water daily to the watershed while eliminating wildfire fuel.
2
Build From Waste
Transform removed eucalyptus into a permanent, fire-resistant structure using natural materials—light straw-clay walls, living roof, zero concrete.
3
Enable Regeneration
Create space for native forest recovery—cork oaks, stone pines, wild olive—restoring biodiversity and ecosystem function.
4
Open the Knowledge
Every measurement, technique, and mistake documented. Freely available, forkable, translatable. Architecture returned to the people who need it.
The Origin
How This Design Was Born
Section titled “How This Design Was Born”The idea came to me in the wake of a visit from my in-laws, during which they taught us how to build a wattle fence around our garden to keep the wild boars away. We built the whole thing for free, entirely from locally sourced invasive tree poles, and then interplanted it with wisteria and passion fruit vines to replace it when it rots away in five years.
We then interplanted the fence with wisteria and passion fruit vines — designed to replace the wood when it rots away in five years.
I started to play with the design by directing the poles at 45 degrees instead of 90. The structure became stronger, more dynamic. From here, it was a small step to imagine this trellis wrapping back on itself to create a giant inverted wicker basket dome.
And when you weave a basket, you want the young flexible ones: 1-5 years old, because they will bend easily into place and then dry in mutually supported tension. The dome will shift over time as each euc dries and twists individually, but there’s a ton of flex to the whole structure — so no big deal.
But how do we make this more useful than a shade pergola? Wouldn’t it be cool if we could let the light in but keep rain out? Wrap the whole thing in greenhouse plastic and lash it down with rope. That’ll keep it dry on the inside — the first step towards living off-grid. Add a simple door cut in one of the arches, and we’ve got a greenhouse that will keep things dry.
Now let’s progressively make a few longevity improvements. The first and biggest step is getting the feet dry — getting those euc poles out of the dirt. So we begin with a gabion cage footprint for the walls: a metal cage filled with medium-sized stones. Anchoring the pole ends in the middle of this cage significantly improves the lifetime of the structure. Treat the surfaces with borax, wrap them in greenhouse plastic, and suddenly this thing starts looking pretty feasible as more than just a greenhouse.
The Designs
Choose Your Design
Section titled “Choose Your Design”Standard BioDome
28m² circular wattle dome — €3-5k budget, 50-100 eucalyptus trees. Build Guide →
Earth Sheltered SolarPod
35m² earth-sheltered — cut into hillside, Da Vinci bridge rafters. Build Guide →
