**4. Conclusions**

Due to the settling of steatite powder, the formed surface (bottom face) of a wood-cement steatite powder (WCSP) board was of good quality even without paper overlay. It compares favorably to the surface of paper-faced gypsum boards. Besides, the ASTM D 1037-12 screw withdrawal resistance and ASTM C473-15 nail pull resistance of wood-cement-steatite powder boards were found to be 37% and 11% higher, respectively. When the load was applied on the front face, their bending strength is 69% higher. These panels also exhibit better water-resistance and better reaction to fire than those of gypsum boards. Indeed, with regards to reaction to fire, no ignition was observed for the WSCP, and the remaining mass of both type of boards after 15 min from start of the test was similar. The test results obtained in the present study actually show that wood-cement-steatite powder boards could be classified as a quasi-non-combustible material. While the replacement of cement with steatite powder at a rate of 15% improved the mechanical and thermal properties of the panel, it could also contribute to reduce CO2 emissions caused by cement production. Two-thirds of the raw materials used for wood-cement-steatite powder board production are low cost secondary products from mineral extraction of steatite and lumber production. The above results show that replacing gypsum boards by such an engineered material may be a worthy choice for buildings of the future.

**Author Contributions:** Conceptualization V.-A.V., A.C., B.B., P.B. and C.D.; Formal analysis V.-A.V., A.C., B.B., P.B. and C.D.; Funding acquisition A.C. and P.B.; Investigation V.-A.V., A.C., B.B. and P.B.; Methodology V.-A.V., A.C., B.B., P.B. and C.D.; Project administration A.C. and P.B.; Resources A.C., B.B., P.B. and C.D.; Supervision A.C. and B.B.; Validation V.-A.V., A.C., B.B. and C.D.; Writing—original draft V.-A.V.; Writing—review & editing A.C., B.B., P.B. and C.D. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work is part of the research program of the Natural Sciences and Engineering Research Council of Canada (NSERC) Industrial Research Chair on Eco-Construction in Wood (CIRCERB) through programs IRC (IRCPJ 461745-12) and CRD (RDCPJ 445200-12).

**Acknowledgments:** The authors are also grateful to the industrial partners of the NSERC Industrial Chair on Eco-Responsible Wood Construction (CIRCERB).

**Conflicts of Interest:** The authors declare no conflict of interest.
