Wood-fibre insulation · the honest comparison
Wood-fibre insulation: the same idea as our borate cellulose
The wood-fibre insulation Europe and the USA are excited about, Gutex, Steico, TimberHP, is wood fibre treated with a flame retardant like borate. That’s the exact chemistry family I’ve put in your roof for 40 years. And because paper is wood fibre, our recycled-paper cellulose is arguably the better version: same treatment, fibre that’s already in the market instead of fresh-chipped timber.
I’m Peter Johnson. If you’ve been reading about “wood-fibre insulation” and wondering whether it’s some new wonder material, here’s the straight story: it’s substantially the same product we already make, and in a couple of honest ways, ours is the smarter member of the family.
Plant fibre + borate
same family, recycled feedstock
Straight up
It’s the same idea: plant fibre treated with borate.
Strip away the marketing and wood-fibre insulation is wood fibre with a flame retardant, commonly borate, pressed into batts or rigid boards. That’s the same chemistry family as the borate-treated cellulose we’ve made for four decades. The big overseas brands you’ll see, TimberHP, Gutex and Steico , are doing exactly what I do, just with virgin wood chips instead of recycled paper.
Here’s the bit that ties it together: paper is made from wood fibre. So recycled-paper cellulose and virgin wood-fibre board start from the same base material and get the same borate treatment. They’re not two rival technologies. They’re two forms of one natural-fibre family. One comes as a rigid sheet; ours comes as a seamless pumped-in blanket.
I’ll be honest about the limit too: I make and install borate cellulose, not wood-fibre board. I’m not selling you a sheet of Gutex. I’m telling you about wood fibre because once you see it’s the same idea, you stop thinking of cellulose as the cheap option and start seeing it for what it is, the recycled member of the natural-insulation family the rest of the world is finally catching onto.
Our borate cellulose packed into a timber-frame wall, recycled wood fibre, treated with borate, doing exactly what virgin wood-fibre board does overseas.
Same fibre, same borate
Line them up and they’re cousins, not rivals.
The honest comparison isn't 'wood fibre versus cellulose'. It's two members of one family, plant fibre treated with borate, that mostly differ in feedstock and form.
| Wood-fibre board (Gutex / Steico / TimberHP) | Our borate cellulose | |
|---|---|---|
| Base material | Wood fibre, virgin wood chips / sawmill offcuts | Wood fibre too, recycled paper (paper is wood fibre) |
| Fire / pest treatment | A flame retardant such as borate | Borate (boric acid + borax), same chemistry family |
| Form | Rigid boards and batts (can be used as sheathing) | Loose fibre pumped in as a seamless, gap-free blanket |
| Feedstock | Fresh timber chipped for the purpose | Recycled paper diverted from landfill, ~75–85% recycled content |
Borate isn’t a coincidence either. It’s the stable mineral salt both products lean on for fire and pest resistance. If you want the borate detail, I’ve written it up on the off-gassing guide and the fire side on our fire-resistance answer. Same borate, two natural fibres.
The honest “in some ways better” angle
Recycled-paper cellulose reuses fibre that’s already in the market.
Wood-fibre board chips fresh timber. Cellulose takes paper (wood fibre that’s already been made once) and gives it a second life in your roof. That’s why cellulose has the highest recycled content of any common insulation , around 75–85% recycled paper. Same borate treatment, same natural fibre, but the feedstock is diverted from landfill instead of cut from a forest.
I won’t oversell it: wood-fibre board has tricks cellulose can’t do. It comes as rigid sheets you can use for external sheathing, where loose pumped fibre simply doesn’t apply. So this isn’t “cellulose beats wood fibre at everything”. It’s “same family, and for a pumped-in ceiling or wall, the recycled version makes more honest sense”, lower embodied impact to get the fibre in the first place.
Recycled feedstock
Both are borate-treated wood fibre. The difference is where the fibre comes from, and reusing paper already in the market is the lower-impact way to get it into your roof.
See it for yourself
What the rest of the world calls “the future of insulation”.
Have a watch of how Europe and the USA are building with wood fibre. Keep in mind as you watch: it's plant fibre plus borate, the same idea we've pumped into SE Queensland roofs for 40 years.
Gutex wood-fibre board, rigid sheets of borate-treated wood fibre. Different form, same family as our cellulose.
TimberHP, an American maker bringing wood-fibre insulation to the US market, treated with borate for fire safety.
Wood-fibre batts from TimberHP. Watch how close the fibre looks to what we pump, because it’s the same wood fibre, just virgin instead of recycled.
Where I think this goes
Borate-treated wood fibre is the natural next step.
This next bit is my own view, not a quoted statistic, so I’ll flag it as exactly that. Recycled paper is a finite feedstock. As the world goes more digital and recycled paper gets harder to come by, the obvious next step for natural fibre insulation is borate-treated wood fibre, exactly as Europe and the USA already do it. It’s the same chemistry and the same idea we’ve been installing for four decades.
That’s why I’m comfortable telling you wood fibre is “the future” without feeling like I’m chasing a trend. It’s substantially the product I already make. If recycled paper ever ran short, moving to borate-treated wood fibre wouldn’t be a leap for us. It’d be a change of feedstock, not a change of philosophy. Plant fibre, borate, made and installed by the same family in Tiaro.
Borate cellulose packed dense into a wall during the build, recycled wood fibre today, and the same approach we’d carry into virgin wood fibre tomorrow if it ever made sense.
Honest answers
Wood-fibre questions I get asked.
What is wood-fibre insulation?+
Wood-fibre insulation is a natural building insulation made from wood fibre (usually clean wood-chip or sawmill offcuts broken down into fibre) bound into batts or rigid boards and treated with a fire retardant, commonly borate. It's big in Europe and the USA, with makers like Gutex, Steico and TimberHP, and it's used for ceilings, walls and rigid sheathing. The honest headline is that it's the same broad idea as the borate-treated cellulose we've made for 40 years: plant fibre plus a borate treatment.
How is wood-fibre insulation different from cellulose insulation?+
Less than most people think. Both are plant (wood) fibre treated with borate for fire and pest resistance. The main difference is the feedstock and the form: wood-fibre board uses virgin wood chips pressed into rigid boards or batts, while cellulose uses recycled paper milled into a loose fibre we pump in seamlessly. Paper is just wood fibre that's already been processed once, so chemically and structurally they're close cousins. I make borate cellulose, not wood-fibre board, but I'll happily tell you they're the same family of product.
Is paper the same thing as wood fibre?+
Yes, paper is made from wood fibre. So recycled-paper cellulose and virgin wood-fibre insulation start from the same base material; cellulose just reuses fibre that's already been turned into paper rather than chipping fresh timber. That's why I can say, honestly, that cellulose is wood-fibre insulation made from recycled feedstock: same fibre, same borate, lower impact to get there.
Is wood-fibre insulation treated with borate like cellulose?+
Commonly, yes. A flame retardant such as borate is used to bring wood fibre up to fire-safety standards, the same borate chemistry (boric acid and borax) we use in our cellulose. That's the heart of the comparison: it isn't 'wood-fibre versus cellulose, two different things', it's 'plant fibre plus borate', delivered in two slightly different forms. Borate also doubles as a pest and mould deterrent in both products.
Is recycled-paper cellulose better than virgin wood-fibre board?+
In some honest ways, I'd argue yes. Cellulose has the highest recycled content of any common insulation (around 75–85% recycled paper) so it diverts paper from landfill instead of chipping fresh timber. Same borate treatment, recycled feedstock, lower embodied impact to get the fibre. Wood-fibre board has its own advantages. It comes as rigid sheets you can use for sheathing, which loose cellulose can't. So it's not 'one wins everywhere'; it's 'same family, and the recycled version makes more sense for a pumped-in ceiling'.
Do you sell wood-fibre insulation board?+
Not at the moment. We make and install borate-treated cellulose, which is the recycled-paper member of the same wood-fibre family. I'm telling you about wood-fibre board because it shows you that the chemistry we've used for decades is exactly what Europe and the USA are now calling the future of natural insulation. If recycled paper ever gets scarce, borate-treated wood fibre is the obvious next step, and it's substantially the same product we already make.
Happy with a roof full of natural, recycled wood fibre? Tell people.
A quick honest review genuinely helps a small family business, and helps the next person decide. Thank you.
Want the recycled member of the wood-fibre family in your roof?
We make our borate-treated cellulose in Tiaro and pump it in ourselves, natural wood fibre, recycled feedstock, same borate chemistry the rest of the world now calls the future. Send me your address and I’ll give you a fixed-price quote, and you’re welcome to come and see the factory.