Application: Cross Laminated Timber
Solid wood building elements such as CLT panels can be insulated on either facade with one or several layers of wood fibre insulation boards or/and with a combination of natural wood fibre insulation batts.
The following are just a few samples of the different external timber wall builds up that can be achieved depending on your project.

CLT - Sample 1
Single layer insulation with Render finish
-
Inner lining (Plaster board / OSB
-
Timber i-joist or timber studs​
-
Steico Flex036​ between the studs
-
Wood-fibre insulation boards (Universal / Duo Dry / Special Dry)
-
Cladding with rear ventilation

CLT - Sample 2
Multi-layer insulation with render finish
-
Inner lining (Plaster board / OSB
-
Timber i-joist or timber studs​
-
Steico Flex036​ between the studs
-
Wood-fibre insulation boards (Universal / Duo Dry / Special Dry)
-
Cladding with rear ventilation
CLT - Sample 3
Single layer insulation with cladding & rear ventilation
-
solid timber wall, e.g. CLT (Cross Laminated Timber), 95mm
-
Wood-fibre insulation boards
(Duo Dry / Special Dry) -
Timber battens
-
Cladding with rear ventilation

CLT - Sample 4
Multi-layer insulation with cladding & rear ventilation
-
solid timber wall, e.g. CLT (Cross Laminated Timber), 95mm
-
Wood-fibre insulation boards
(Duo Dry / Special Dry) -
Timber battens
-
Cladding with rear ventilation

What are the benefits of external insulation boards ?
-
External insulation layer provides thermal bridge free construction.
-
Provides an additional weather & water protection layer
-
Improves sound proofing properties of the building envelope
-
Boards can be exposed to the elements for up to two months
-
Vapour open allowing moisture in the building fabric to escape
-
Reduces air draughts due to its Tongue & Groove design
-
Provides additional bracing strength to the building element
-
Adds additional fire resistant qualities to the building envelope
Which wood-fibre boards for CLT wall insulation ?
Rigid STEICO wood fibre insulation boards for cladding or render applications for CLT wall include the STEICO Duo dry and Special Dry.
Board thickness from 40mm - 180mm are available and are particularly water vapour diffusion open.
They are classified as sheathing and sarking boards, meaning they can support a load, and are also rain proof. i.e., water-repellent. Rainwater’s surface tension cannot break through sarking boards.
Waste on site is minimised as you can reverse the boards.
Insulating massive flat roof elements


Downloads
Installation Guide for Sheathing & Sarking boards.
Additional documents on our Downloads page.