Experimental investigation on the effect of openings on the in-plane shear strength and stiffness of cross-laminated timber panels

•The influence of openings on the strength and stiffness of cross-laminated timber (CLT) walls was experimentally evaluated.•The reduction in stiffness for CLT walls due to openings is relatively greater than that in strength.•Panels with rectangular openings with different orientations had different failure direction and reduction factors.