The European market for cross-laminated timber (CLT) is rapidly growing in the field of multi-story residential buildings. However, water leaks repeatedly lead to severe moisture damage in timber buildings. Undetected moisture damage may result in biological degradation of the CLT structure, is difficult to repair, and incurs high costs. Currently, there is a lack of awareness of the fact that timber buildings require different mechanical, electrical and plumbing (MEP) installation methods than buildings made with mineral construction materials. In addition, too little attention is given to protecting the wooden structure by applying appropriate sealing measures that actually work in practice. Lack of planning and uncoordinated construction work exacerbate this problem. Presenting 2D drawings and 3D BIM models, the paper illustrates concepts that can be used to optimally design and safely integrate MEP installations in bathrooms in multi-story residential timber buildings. A special focus is placed on a holistic view of the topics structure, pipe installation, sealing, and fire protection. The concepts presented are based on an analysis and classification of over 1100 bathroom layouts. Therefore, they are applicable to a wide range of bathrooms in practice. The presented results were developed in the research project CLT_Plumbing_Design. They contribute to the development of standardized, timber-specific solutions for pipe installation and sealing in bathrooms, and can help reduce moisture damage in timber construction. In addition, these concepts form a basis for a new automated planning process in the area of bathroom planning, for which a brief outlook is given.

In the last years building activity with solid Cross Laminated Timber (CLT) elements gained remarkable relevance. Starting with single family houses over 15 years ago medium and large sized building construction jobs are analysed and solved in the meantime. Two examples for large multi-storey houses with eight floors each, erected completely with CLT, can be cited here: on the one hand the Murray Grove Tower (2008) and on the other hand the Bridboard House (2010) - both realized in London. Structural design of these CLT-plates is performed traditionally as simply supported uniaxial plate. Only the stronger, more important main direction of CLT-plates, which is defined as the orientation of the outer layers, is treated by this assumption. In order to include the minor important orthogonal direction of CLT in a two dimensional plate theory all plate stiffness coefficients of CLT-plates are illustrated and discussed in the present paper. Consequently special cases as large cutouts in CLT-plates and column supported CLT-plates can be treated with the well known REISSNER-MINDLIN plate theory, which includes deformation due to bending and shear.

This contribution deals with the influences of time and those relevant to bearing capacity on the reliability of historic timber roof structures. Furthermore the evaluation as well as damage analysis of historic roof structures are discussed. Based on this an easily comprehensible and documentable methodology temporarily only for roof structures in the area of Graz is presented and illustrated with examples.