Many serious defects may be shown to have causes outside the materials or techniques used in the plastering operations and it is often useless to replace the plaster without. Pdf effect of gradation of fine aggregate on development of. In this new version, the same functionality that our users have learned to love over the years still exists, but with some improved features based customer feedback and input. It is a makeup work over walls by applying cement mortar plastering. Jun 29, 2019 types of plaster pdf or types of plastering in building construction pdf can be downloaded from here.
Cracking cracking may result from one or more of the following. How to minimize the defects in plaster work bob henry. The development of a series of hair cracks on the finished plaster surface. Blistering of plastered surface small patches swell out beyond the plane of the plastered surface and this defect is particularly seen in case of plastered surfaces inside the building.
Crazing is a network of fine cracks, usually in a hexagonal pattern, which measure between 5 and 75 mm across each hexagon. The brick and plastering work should be carried out by skilled masons in the best workmanship manner. Schedule of building defects the following is a list of newly identified defects that exist in the finishes and the quality of those finishes, for which rectification can reasonably be expected to be the responsibility of the builder. Reprinted with permission from kim skinner of on balance identifying plastering defects on new pool plaster. Plastering a painted pool if your pool is painted plaster or concrete and you are interested in upgrading the finish to plaster, then the paint needs to be removed from the existing surface because the paint is a barrier which will prevent the new plaster from adhering to the surface. Pdf on mar 5, 2014, nurul nadia omar bakri and others published general building defects.
Visible joints can be hidden by cover strips fixed on one side of the joint or sealed with elastomeric sealants. Remove oil, grease dirt or any other contaminants with polycell sugar soap powder solution. Known as map crazing, when it forms a haphazard pattern over the wall surface. A mixture of lime or gypsum, sand and water sometimes with fibre added, that hardened to a smooth solid and used for coating walls and ceiling. Before you begin actual plastering, use water free from salts to water the surface you will plaster. The surface finish can be obtained as smooth, semirough or rough as per the desired aesthetic appearance using ganging trowel, regi foam and sponge. Honeycomb is mainly manifested by local loosening of concrete, less mortar, more gravel, and voids between gravel, forming honeycomblike holes. Nonstructural cracks structural cracks debonding lack of hardness grinning expansion popping the causes and repair methods for each are discussed below. Plaster finished surface also gives insulation to thermal, fire and sound. Defects most frequently noticed in plaster fall into one of the following categories. Building defects can categories into two which are patent and latent defects rhodes and smallwood, 2002.
It is not possible to give simple rules for the correction of all plastering defects or failures. Sep 01, 2015 reprinted with permission from kim skinner of onbalance if npc national plasters council leaders would just acknowledge what improper plastering practices do to swimming pool plaster, there would not be a controversy within the industry and there would be fewer pool plaster defects and discolorations occurring. Types of plaster pdf or types of plastering in building construction pdf can be downloaded from here. Classification of factor affecting external wall defects focusing on. Let us now understand the reasons of occurrence of these. Factors affecting the performance of concrete structures concrete is one of the composite materials normally used at every stage of construction and it may suffer damages or defects en 1992en 1. Lime are used in wall lime mortar, lime plaster, lime wash, floor and roof. This is the formation to small patches of plaster swelling out beyond the plastered surface, arising out of late slaking of lime particles in the plastic cracking. Plastering as building finishes and the defects basic civil. Blistering the development of one or more local swellings on the finished plaster surface. Different types of defects occur in plastering work such as blistering, cracks, efflorescence. May 30, 2017 apart from cracking plaster, several other plastering defects can occur. Jun 23, 2011 reprinted with permission from kim skinner of on balance identifying plastering defects on new pool plaster.
Common defects a paint defect is in many cases due to a number of causes. John roxburgh, lecturer at the concrete institutes school of concrete technology, explains why. They are usually the result of over trowelling a rich mix one with high cement content or using sand containing an excessive amount of dust more. Jul 21, 2017 minimising defects in plastering work. Gray or grey mottled discoloration also known as water entrapment.
Jun 15, 2019 plastering is enhancing the aesthetic value and hygiene condition in a building. Plaster, especially excessively thick layers, is inclined to debond from the wall when the outside skin shrinks at a different rate than the plaster in contact with the wall. Reprinted with permission from kim skinner of onbalance if npc national plasters council leaders would just acknowledge what improper plastering practices do to swimming pool plaster, there would not be a controversy within the industry and there would be fewer pool plaster defects and discolorations occurring. Finished grooves shall be neat, of uniform width and depth, sharp straight edges and exact vertical and horizontal lines.
Oct 15, 2017 neither you have to peel it all off and do the whole procedure again. Defects commonly observed in plastering supervision tips. Such measures may include structural alterations which change cracks into movement joints. Nov 03, 2014 blistering the development of one or more local swellings on the finished plaster surface. Different types of defects occur in plastering work such as blistering, cracks, efflorescence, flaking, peeling, popping, softness and uneven surfaces. Apart from cracking plaster, several other plastering defects can occur. Al nasra, phd, pe 9252008 concrete methods and principles, 1 c al nasra. However, there are certain principles that must be adopted of difficulties may arise. This method of statement for plastering includes the following.
Defects in plastering work can be minimised by following the below mentioned techniques. Known as map crazing, when it forms a haphazard pattern. Efflorescence is removed by rubbing brushes on the damaged surface. Please also see practical alternatives to using step ladders part 1. Regarding recessed, follow the procedures same as grooves. Some vital plastering defects and remedies to resolve them. Plastering is enhancing the aesthetic value and hygiene condition in a building. Restraint of movements brought about by drying shrinkage. Causes, symptoms and remedial work find, read and cite all the research you need on researchgate. This is the formation to small patches of plaster swelling out beyond the plastered surface, arising out of late slaking of lime particles in the plastic.
Usg uses the term shadowing in this document in describing the visual effect over gypsum board joints caused by the lower moisture. Crazing the development of a series of hair cracks on the finished plaster surface. Defects in plastering plaster defects and remedies. To achieve good painting work, applicators and site supervisors should understand the causes and. Damaged edges are more susceptible to ridging after joint treatment fig. Plastering defects and remedies plastering defects remedies 1. While painting, brush is moved from top to bottom and then from right to left and in the end the brush is slowly moved after bringing it from. The defects pro task list app was built on the foundation of our popular defects mobile app that has been around for years. Live knot a knot free from decay and other defects, in which the. The background should be prepared and a coat of thistlebondit applied prior to the application of a suitable grade of plaster refer to.
Besides, cracking, there may be other flaws with plastering. This will enhance the attaching of plastering material and prevent the surface from sucking the water out of. Here is just some useful advice on how to minimize the defects in plaster work and make it look smooth and quality. They are usually very fine and shallow and do not extend through the whole depth of the plaster. These cracks normally occur when a plaster mix with a high cement content is used or the plaster is allowed to dry too quickly. Aug 05, 2019 defects commonly observed in plastering 1. Construction punch list check list category item reported completed did you run your dishwasher through one full cycle are shut off valves installed at all water connections i. Maximum chloride ion content of concrete aci 318 maximum type of member cl prestressed concrete 0. Fill defects with the appropriate polycell polyfilla. The primary defects appear in plastering are discussed below.
Plastering as building finishes and the defects basic. Code of practice for application of cement and lime plaster finishes first. Standox gmbh postfach d42271 wuppertal germany 44070578 gb 10 05 2000. Nonstructural cracks crazing is a network of fine cracks, usually in a.
Outstanding item from frame report dated thursday 8th december 2016 s1 angle brace cut depth. Many serious defects may be shown to have causes outside the materials or techniques used in the plastering operations and it is often useless to replace the plaster without first having discovered and corrected the primary fault. The surface of the second coat shall be brought to a true, even plane with a rod or straightedge, filling surface defects in place with plaster. John roxburgh who performs lecturer at the concrete institutes school of concrete technology, highlights the following points for plastering defects as well as proper solutions for resolving them. It is also essential to use some recommended details to better manage the defects and implement necessary remedial actions. Designers, contractors and site supervisory staff should understand the common defects and their related causes to prevent them.
In case if you are speaking about the method of doing the plaster it can be method by using the bamboo scaffolding, cuplock type scaffolding type. The article you are describing is about the places where plastering is to be done it doesnt indicate the methods of plastering. Deicing salts are a major cause of corrosion of reinforcing steel in concrete. A case study on moisture problems and building defects. In some cases, several defects may occur simultaneously and hinder the determination of the causes and redemption works. With the correct attention to detail a good troublefree service life can be obtained. Cracking the development of one or more fissures not assignable to structural cause. Plastering, painting and polishing 99 taking the paint through brush so that the texture of the paint remains the same. We can divide whole plastering process into two broad category.
These defects in plastering need to be repaired as soon as they are observed. Methods of plastering can be manual method or mechanical method. Pdf on mar 5, 2014, nurul nadia omar bakri and others published general. Pdf common defects in plaster zulfiquar ahmad academia. Pool equipment warranty will be in effect from the manufacturer for 3 years from the date of installation.