Straw facade
insulation
The rigid straw board is a biobased insulation for facades. Its structure of plant fibres improves the building's thermal insulation while making use of a renewable agricultural resource.
What is straw facade insulation?
The rigid straw board is a biobased insulation for facades, made of lignocellulosic fibres from cereal straw in a dry process with no synthetic glue. The fibres act both as the insulation and as the loadbearing matrix, with the straw's natural lignin binding them together under pressure and steam. No added binder is needed.
The board remains vapour-open and lets the wall breathe, while providing thermal insulation equivalent to that of common biobased insulation materials. Its rigidity makes it a suitable substrate for render in external wall insulation.
The product is therefore used as external wall insulation on facades, over timber or masonry substrates, in place of a synthetic board. It is laid with tightly butted joints, bonded and, where required, mechanically fixed.
It is manufactured in Poland by Vestaeco, from annual agricultural fibres sourced from the local cereal-growing area. The board can be composted at end of life, and the producer holds a verified environmental product declaration.
Installation & uses
The board is bonded to the wall with a suitable adhesive mortar, supplemented where necessary by screw-in anchors depending on the substrate. Joints are butted tight and dry, with no foam or added jointing, and the boards are cut with a saw or a hot wire depending on the thickness.
Once fixed, the board receives a mesh-reinforced base coat, then a finish coat. The system forms a breathable external wall insulation ready to take a render finish.
The product suits new build as well as envelope renovation. On exposed facades it copes with moisture through its breathability, provided it is finished on the outside with a suitable render.
At end of life, the board can be detached from its substrate and sent for composting. Offcuts from site can be composted directly.
About the producer
Vestaeco is a European producer of biobased straw-fibre insulation, based in Poland. The company makes its boards in a dry process with no synthetic glue, from straw grown by local cereal farming.
Its range covers facade insulation, under-screed insulation and roof insulation, with the same base material and the same short supply chain. The producer has had the environmental impact of its boards verified through an official declaration.
Technical performance
EN 13171 (wood fibre and lignocellulosic insulation products)
FAQ
Which thickness should I choose?
Five thicknesses, from 40 to 200 mm. Conductivity 0.043 W/m·K, under product standard EN 13171.
Can it be left exposed on a facade?
No. It copes with moisture through its breathability, but only if it is finished on the outside with a suitable render. That is the condition for use on an exposed facade.
How does it behave in fire?
Class E. This is the point to address on facades: the wall build-up and the added protection determine whether it can be used.
What happens to it at end of life?
The board is entirely biobased, compostable and biodegradable. Straw is a resource that renews every year.
Alongside
Same layer, same use · three materials to compare.
