Assessment of selected physical, mechanical and calorific properties of post-consumer spruce Picea abies (L.) H. Karst wood - a case study

The article presents the characteristics of the physical, mechanical, and calorific properties as well as the elemental composition of post-consumer wood. The study was applied to approximately 100-year-old spruce Picea abies waste from the conservation of the roof truss at the Parish Church in Gilowice and building structures from the Open-Air Museum in & Sacute;lemie & nacute;. Studies were carried out to determine the possibility of safely use of the discussed post-consumer timber waste. Based on applicable standards, wood density, compressive and static bending strength of wood, elemental composition and calorific properties were determined. The tested wood presented a density approx- imately 7% lower compared to fresh wood, and it exhibited lower resistance to bending and compressive stress, whereas its lignin (xylogen) content tested over 30% higher. The calorific value was on average 18.79 MJ<middle dot>kg-1, and the ash content did not exceed 1%. The tested wood samples meet the standards of construction wood ISO PN-EN 338:2016-06 class C40.