Timber-framed house on Fejø
Oak timber frame renovated with hemp blocks, Denmark
An oak timber frame was renovated on the Danish island of Fejø. The project shows how hemp blocks can be combined with a historic structure.
Infill panels and lining
The infill panels were bricked up with 9 cm thick hemp blocks. A second leaf of 12 cm thick hemp blocks follows on the inside, with the gap filled with hemp-lime fill.
Plaster and paint
The wall received a mineral lime base plaster (HP 9 by Hessler), followed by a coat of the titanium dioxide-free silicate paint BEECKOSIL by Beeck.
What matters with hemp blocks
What matters is how everything works together: hemp blocks, mineral plaster and mineral paint form a system. And as with any thin-bed masonry, a perfectly level first course determines the success of the whole wall.
The insulation value of this wall
U = 0.27 W/(m²K)
U-value of the external wall from the building owner’s heat demand calculation
| Layer, from outside to inside | Thickness |
|---|---|
| Lime base plaster | around 2 cm |
| Hemp block in the infill panel | 9 cm |
| Hemp-lime fill | around 4 cm |
| Hemp block as inner leaf | 12 cm |
| Interior plaster | around 2 cm |
For comparison: our own calculation for the infill panel only, without the oak beams and using the rounded thicknesses above, gives around 0.26 W/(m²K). The values apply to this build-up and do not replace verification for your project.
Photos: building owner