L11: Interior Construction Flashcards
What are the types of interior walls?
Fire walls
Shaft walls
Fire/smoke barriers
Other non-bearing partitions
What are fire walls?
Walls which extend from foundation to above roof level and subdivide building into smaller units to restrict the spread of fire
What are shaft walls?
Encloses multi-storey openings through buildings eg. lift shafts, chases, risers
What are the typical fire ratings for shafts that are less/more than 4 storeys?
Less that 4 storeys - 1h rating
More than 4 storeys - 2h rating
What must lift shafts also do?
Withstand air pressure loads from moving lift
Control noise
What are fire/smoke barriers?
Similar to fire walls but do not extend through entire building - go from floor slab to underside of ceiling
What do fire/smoke barriers do?
Subdivide larger areas into fire cells
What are the common types of commercial partition framing?
Light gauge steel studs (most common)
Metal furring over solid walls
Why is metal common partition framing and not wood?
Wood is combustible, heavier (more dead load), and is capable of bearing loads which is not required
What are light gauge steel studs finished with?
Gypsum sheathing but can also have plaster finish
How are runners fastened in light gauge steel studs?
With power-driven fasteners
What is metal furring over solid walls?
Metal furring attached with power driven fasteners to solid walls to increase fire rating and acoustic contol
What finishes do metal furring over solid walls have?
Gypsum board - provides space between wall and finish for insulation/wiring
Plaster - grid of adjustable furring channels; good for producing flat wall
What channels do gyp board finished metal furring over solid walls have?
Z channels - no weak point
Hat channels - weak points
What are the types of rough wall finishes?
Plaster
Gypsum board
How common are plaster finishes in NZ and why?
Not common - labour intensive, applied wet (heavy)
How common are gypsum board finishes and why?
Most common - highly standardised (mass produced and interiors made to fit), labour efficient, applied dry (lightweight)
What are the types of plaster applications?
Interior - gypsum plaster (expands)
Exterior - portland cement-lime plaster (stucco) (shirnks)
What are plaster bases for?
Surface placed on studs for plaster to adhere to
What are the types of plaster bases?
Metal/wire lath, gypsum lath, wood strips, none
When can plaster bases not be used
When the wall material itself is porous eg. CMU, brick
What are the two systems for applying plaster and when are each used?
Three-coat system - used with metal lath
Two-coat system - used with gypsum lath
What are the three coats in the three-coat plaster system?
Scratch - forms rigid base (scratched)
Brown - builds thickness and levels surface (scratched)
Finish - final, level surface
How is the two-coat system different from the three-coat system and why?
No scratch coat because gypsum lath is rigid
What is plasterboard (gypsum board)?
Plaster placed between two sheets of paper (prefabricated)
What are common types of gypsum board?
Regular
Water-resistant (green board)
Type-X (fire resistant)
Type-C (extra fire-resistant)
What are common thicknesses for plasterboard?
10mm and 13mm
6mm can be curved
What do the edges of plasterboards have?
Tapered to allow tapering and floating
What is required with plasterboard to strengthen/protect corners?
Corner beads fastened to metal studs with self-tapping screws and screw gun
What is taping and floating and how is it done?
Joint compound and reinforcing tape applied over joints and fastener holes, then sanded down and wiped clean for final finish
What are common wall finishes?
Paint
Wall covering
Wall tile
How is interior wall paint final finish applied?
1 coat of primer
2 coats of finish finishing
What are the final finishes used?
Light duty areas - latex plat wall paint
Moderate duty areas - washable flat or semi-gloss
Heavy duty areas - gloss or semi-gloss enamel
What are wall coverings and what are the advantages/disadvantages compared to paint?
Fabric-backed polyvinyl chloride sheets
Advantage - easily cleaned and damage resistant, hides imperfections
Disadvantage - more expensive
What wall coverings are used in hygienic areas?
Plastic coverings
How and where are wall coverings installed?
Installed with adhesive
Can be applied on new walls and existing finishes