Presentation on theme: "Materials used for the roof structure and joinery components."— Presentation transcript:
Materials used for the roof structure and joinery components
Timber Both sapwood and heartwood are in use in the construction industry. Both have approximately equal strength but heartwood is naturally more durable than sapwood. Wood is an organic material which should only be used from forests which are replanted once the timber has been felled. Sapwood The outer active part of a tree, which as it’s name implies, receives and conducts sap from the roots to the leaves. As this part of the tree matures it gradually becomes heartwood. SapwoodHeartwood
Timber (solid) Heartwood The natural non-active part of the tree, often slightly darker in colour than sapwood, gives strength and support to the tree and provides the most durable wood for conversion into timber. Bark The outer sheath of the tree. It functions as :- a moisture barrier thermal insulator an armoured plate against extremes in temperature, attack by fungi, insect and animals. SapwoodHeartwood
Softwoods and Hardwoods The term Softwood and Hardwoods refer to the botanical origins of wood and not to their density or physical hardness. Softwoods Softwoods come from cone-bearing trees, often with evergreen needle-like leaves. Softwood trees are usually much faster growing than hardwoods. Softwood are generally used for roof timbers, dividing walls, garden decking or any other location where timber is used structurally but the appearance is not important.