External plaster is used on the building elements. This is done on concrete, stones or other building facades for aesthetics. It can also be used to protect masonry or concrete surfaces against weather agents. It can be painted, coatings applied or left plain. The plaster should be done correctly for it to be durable. If the correct mixes are not used, it flakes from the wall surfaces. It is also used as backing material for banners or adhesive for external wall tiles.
When constructing a house, some areas on the outside are not usually visible. The external plaster is used in this areas as a natural finish. This in particular inside the eaves, under projecting landings or bay windows above the ground level. The tools for this work involve a hawk, trowel, steel and wooden float. When the surface is not exposed like on covered verandas, the steel float can be used. When plaster is for general external wall or column or free standing surfaces then a wooden float is advisable.
The external wall surface is prepared for plaster as for the internal walls. This should be made to be fair faced by chiseling any protruding concrete or masonry. Spacer marks are then done using a straight edge, level and string. This allows the work to be aligned properly due to the large surfaces involved. After the marks are dry then the work can commence. The mix for application is one part cement to three parts sand. For surfaces that are to be left with plaster as an only finish, add half a part of cement to the mix.
Once the mix for plaster is ready, the surface is thoroughly wetted with water. A slurry mix is first applied over the surface to give the other coats a backing. The medium wet mix is then applied and a straight edge used to check the thickness and straightness. The wooden float is then used to smoothen the applied plaster. A paint brush can be used to wet the plaster so that the floating remains consistent. The upwards strokes should be used with the wood float finish. After drying for about two weeks then painting can be applied or other paste finishes.
Related : Outdoor Living on Sale Who is Civil Engineer
ไม่มีความคิดเห็น:
แสดงความคิดเห็น