Is Wood Fibre Insulation Attractive To Pests? – Can I Just Ask? | Ep.18

Given that wood fibre insulation is made from natural materials, it’s understandable that clients occasionally worry about it attracting pests—particularly insects, rodents, or even nesting wasps. But how justified are these concerns? In this article, we explore how wood fibre insulation is processed, what makes materials attractive to pests, and why proper detailing matters far more than material choice when it comes to infestations.

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Wood Fibre vs Woodworm: Clearing Up the Confusion

It’s a question that comes up surprisingly often: if insulation is made from wood fibres, doesn’t that make it appealing to wood-boring insects like woodworm or beetles?

The answer, reassuringly, is no. The confusion stems from a false equivalence between solid wood and processed wood fibre. In truth, wood fibre insulation undergoes a manufacturing process that changes both its physical structure and chemical composition – especially in wet-processed boards, where much of the natural sugar content is removed.

These sugars are what insects such as wood-boring beetles are typically after. Without them, the material simply isn’t appetising. More importantly, the insulation’s structure doesn’t provide the dense, load-bearing environment wood-boring insects need to thrive. In over two decades of experience with wood fibre products, we’ve never encountered a case of insect infestation in correctly installed insulation.

Rodents: More About Access Than Appetite

Rodents are another common concern. Mice and rats are opportunistic and highly adaptable; they’ll nest in anything warm and sheltered if they can find a way in. But again, this isn’t unique to wood fibre. Given the chance, they’ll make themselves at home in PIR, mineral wool, or just about any other insulation material.

The takeaway? If your insulation is accessible to rodents, something’s gone wrong with the detailing. Airtightness, sealing, and protecting vulnerable junctions are all critical—not only for energy performance, but for keeping unwanted visitors out.

Flying Insects and Other Intruders

People sometimes ask about flying insects too—wasps, bees, even ants. But again, there’s no evidence to suggest that wood fibre is particularly appealing. In fact, even ants (which happily burrow through many materials) tend to avoid it. If insects are turning up inside a build-up, it’s usually due to poor sealing at service penetrations, eaves, or junctions—not the insulation material itself.

Good Detailing is the Best Defence

Ultimately, pest resistance comes down to construction quality rather than material selection. Even the most inert insulation won’t stop insects or rodents if the building envelope isn’t well sealed. But with properly detailed junctions, well-fitted boards, and secure closures, wood fibre insulation performs just as well—if not better—than its synthetic counterparts when it comes to keeping pests out.