WP 4 Development of cellulosic in-situ spray-on materials

Leader: VTT
Participants: FCBA, Soprema

The objective of WP4 is to explore the ways to produce self-curing in-situ spray-on insulation foam from fibrous (ligno)cellulosic raw materials.

Spray foam insulation is an alternative to the use of insulation batts or boards. Existing spray-on foams are based on the reaction of isocyanate and polyol and depending on components ratio they are forming polyurethanes (PUR) or polyisocyanurate (PIR). In addition of health effects of the isocyanate component, also the other component polyol has its disadvantage – polyols are traditionally mineral oil based. In-situ applied, so called loose-fill cellulose products include dry-blown cellulose insulation, spray applied cellulose (wet-spray), stabilized cellulose (very small water amount) and a low-dust variation (small amount of oil or other dust dampener added).

Although many types of cellulose fibre based thermal insulation materials exist, none of them forms a closed foam structure that can be sprayed into wall cavities, or through holes drilled in into a cavity of a finished wall. In this project we aim to develop cellulose based spray foam material which is as good insulation material and as easy to be sprayed in-situ at construction site as polyurethane spray foam.

Cellulose foam will not have the undesired health and safety issues of polyurethane foam and its environmental impact will be essentially lower. The idea is to use such cellulosic raw materials that are able to create similar pore structures compared to polyurethane foam. The insulation material will be self-curing and keep its shape. Appropriate water repellence and fire performance properties will be developed to the material.