1 / 19

Internal solid plastering

Internal solid plastering. Internal solid plastering. Internal plastering covers walls and ceilings, prior to decoration. A variety of materials can be used to provide a sound, flat, smooth surface for decoration. Sometimes, decoration is needed.

maine
Download Presentation

Internal solid plastering

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Internal solid plastering

  2. Internal solid plastering • Internal plastering covers walls and ceilings, prior to decoration. • A variety of materials can be used to provide a sound, flat, smooth surface for decoration. • Sometimes, decoration is needed. • Plastering provides sound and thermal insulation. • It also improves levels of hygiene, allowing for wiping down.

  3. History of plastering • Plaster is at least 4,000 years old. • It was used by the Egyptians (in the pyramids) and the Greeks (who produced plasterwork in 500 BC). • The Romans introduced plastering to England. • Henry III admired the whiteness and fineness of gypsum (‘Plaster of Paris’), so he brought it to England. • Plasterers were formed into a guild (a company) which was granted a charter by Henry VII. Decorative ceiling and frieze

  4. Examples of some tools and equipment used for internal plastering • Hawk • Trowel • Floats • Spirit level • Gauging trowel • Spot board and stand • Floating rules • Mixing equipment • Internal angle trowels • Other tools and equipment required

  5. Preparation of background • What is adhesion? • What is suction and how does it improve or hinder a plasterer?

  6. Surface key is it good , moderate or poor • Good key: • if joints are raked out • keyed blocks • when keyed bricks are used • Moderate key: • flush brickwork or blockwork • Poor key: • flush brickwork or blockwork • unless surface has been keyed in manufacture • Preparation required prior to plastering • Brush and damp down according to suction. • Rake out soft joints in old brickwork. • Test suction if poor and apply spatterdash coat. • Mechanical key, hand key or spatterdash coat. • Test with bonding agent (PVA). Types of background • Normal clay bricks or blocks • Dense clay brickwork, blockwork, calcium silicate blocks, concrete blocks • Dense concrete, engineering bricks • Painted brickwork, glazed tiles, glazed brickwork

  7. Types of background in British Standard 5262 • Dense, strong and smooth materials • Moderately strong, porous materials • Moderately weak, porous materials • No fines concrete • Composite backgrounds

  8. Forming a key • Purpose of a key • Forming a mechanical key • Forming a spatterdash coat • Using liquid PVA or EVA for forming a key • Forming a key by hacking the surface

  9. Preparation checklist • Brush down background to clean it. • Remove mortar snots from joints, internal and external angles. • Make a key (if needed) to background. • Test background for suction; treat if necessary. • Place drop boards at bottom of wall to catch falling materials and keep floor cleaner. • Fix EML to timber wall and soleplates as necessary. • Fix angle beads. • Set up spot board and stand; wet in the board.

  10. Materials used in plastering • Sand • Lime • Cement • Plaster

  11. Sand • Types and sources of sand • What is meant by awell-graded sand? • What is the purpose of sand? • The effects of bulking • Performing a simple site test for sand • What is silt and how does it affect plastering sand? Sand contained in a sand bay with protective covering sheet

  12. Faults with poor quality sand

  13. Lime • Manufacture of lime • Types of lime • Hydrated lime • Hydraulic lime • Purpose of lime in a plastering mix A lime works

  14. Ordinary Portland cement • Raw materials of OPC • Manufacture of cement • Hardening and curing of cement • Other types of cement • Lightweight cement-based materials

  15. Plaster • Chemical formula of plaster CaSO4 2H2O • Setting of plaster • Types of plaster and their uses • Storage of plaster and effects of poorly stored plaster • Method of mixing different types of plaster

  16. Plaster coats – method of work • One-coat work • Two-coat work • Three-coat work • Dubbing-out coat • Render coat

  17. Forming box or broad screed • The purpose of screeds • The method of forming screeds, horizontally and vertically • Method of ruling off screeds • Filling in between screeds • Method of forming a key between plaster coats

  18. Dot and screed or plumb and dot • Use of the dot and screed or plumb and dot system • Method of forming dot and screed and plumb and dot systems

  19. Setting coat • Method of forming a finishing coat depends on background • Finishing coat should not be stronger than backing coat • Purpose of a finishing coat • Method of forming a finishing coat to a floated background • The setting system; trowel, trowel, and trowel, float, trowel

More Related