glulam | KVH

IMPORTANT INSTRUCTIONS ON THE HANDLING AND STORAGE OF GLULAM Packaging, storage and climate conditions BSH is always delivered packed in stretch wrap (unless special customer wish is on hand). With regard to glulam elements, the bottommost element in the package is packed facing upward for protection against fork lift forks; all others are packed facing downward. When glulam is stored, it is advisable to protect the wood adequately against weather influences. The stretch wrap or protection foil is nothing more than a short-term trans- portation protection and cannot deliver long-term protection from UV radiation and rainfall. In general, with regard to storage, it has to be ensured that the moisture content of the glulam beams does not alter negatively on account of disadvantageous influences, e.g. from soil moisture, rainfall or drying up. The storage on the construction site should never be long. The beams have to be stacked on flat supports and/or bed timber. The beams have to be laid out completely flat so as to prevent imprints. Improper storage can result in lasting visual and even static damage to the glulam beams. Manipulation and assembly In order to prevent damage to the BSH in the area of edges and surfaces, they have to be handled with great care. Suitable lifting tools and lifting means have to be deployed (harnesses, loops with edge protection, no chains for strapping). Especially when handling the exposed elements, unnecessary soiling of or damage to the surfaces and edges is to be avoided. Once the beams are integrated into the construction, the exposed surfaces have to be continuously protected from soiling and/or damage as well as against moisture influences (e.g. by covering the exposed surface with foil, cardboard and suchlike). Minor damage or soiling cannot always be 100% prevented during loading, transportation and assembly. This does not establish grounds for complaint. Reworking such as planing and other rectifications has to be taken into account already with the offer calculation! Fissures / shrink fissures The BSH is delivered with a moisture content of max. 14 %. The fact that wood changes its volume in the hygroscopic range (from 0 to 30 %moisture content) due to swelling and shrinking processes entails that shrink fissures can occur in the wood. This does not establish grounds for complaint. The wear of wood, especially outside, is enormous due to fluctuations of temperature and humidity. Shrink fissures can occur in glulam wood, although to a much smaller extent than in solid wood. Owing to the varying material behavior of the glued lamellas between glue and wood, the shrink fissures often run parallel to the glue joints. These are not mis-gluings but material-related qualities. Weathering, graying If BSH are exposed to weather conditions, degradation products of the lignin destroyed by UV rays will be washed out by rain water. This natural weathering of the wood amounts to an average of 1 mm in 10 years and results in relief formation on the surface of the element. When BSH are used outside, it is principally possible to forgo chemical wood protection. There are some building law regulations in place in this context that demand structural or chemical wood protection. If untreated wood is exposed to weather conditions, the graying process sets in after a few months. The gray coloration and subsequent weathering of the element‘s surface exposed to the weather do not constitute a technical defect.