ASSIGNMENT  5 Textbook  Assignment: Chapter 7   -  Plastering,  Stuccoing,  and  Ceramic  Tile Chapter 8 -   Structural  Coatings  and  Preservatives 5–1. Which  of  the  following  plaster binding  materials  should  NOT  be exposed  to  severe  moisture? 1. Portland  cement 2. Lime 3. Gypsum 5-2. Which  of  the  following  statements best  describes  gypsum  gauging plaster? 1. Contains  lime  putty  which increases  the  dimensional stability  of  the  plaster  while drying  and  provides  initial surface  hardness 2. Has a high density, yields a highly  polished  surface,  and provides  crack  resistance  when used with fine sand 3. Contains finely ground gypsum with  or  without  aggregate 4. Contains  no  admixtures  and  is designed to reduce sound 5-3. Gauging material is added to lime plaster for which of the following reasons? 1. To  induce  shrinkage  and  produce early  strength  only 2. To induce late strength and counteract  shrinkage  tendencies only 3. To  produce  early  strength  and counteract  shrinkage  tendencies only 4. All of the above 5-4. Portland  cement  plaster  should  NOT be applied directly over what type of walls? 1. Exterior  masonry 2. Interior  masonry 3. Interior  or  exterior  metal-lath covered 4. Gypsum  tile  or  plasterboard 5-5. When  the  aggregate  material  is excessively fine grain, why is the plaster  strength  reduced? 1. 2. 3. 4. The smaller quantity of water required raises the water to cement ratio and increases the dry set time The greater quantity of water required raises the cement to water ratio and reduces the dry set density Less binder paste is used because of the lack of space between particles of the fines, resulting in a weak mixture More binder paste is needed to coat all particle surfaces, resulting  in  sufficient  fines to close all voids and leaving a rich but unstable mixture 5-6. Which  of  the  following  aggregates should be used in acoustical plaster? 1. Perlite  only 2. Vermiculite  only 3. Perlite  or  vermiculite 4. Sand 5-7. For  plaster  application,  what  must be  installed  between  structural members to form a continuous surface? 1. Plaster  planes 2. Insulation 3. Lath 4. Fire blocking 5-8. To provide a good key, wood lath plaster base should have what minimum  spacing? 1. 1/4 in. 2. 3/8 in. 3. 1/2 in. 4. 5/8 in. 26