it's not aluminum nor zinc

it's ZINCALUME - zinc and aluminum alloy

and either material is common roofing material. it's been used for ages, besides the ubiquitos concrete / clay tiles

i know cos i design roofs - engineering side, not architecture

This post has been edited by lucifah: Sep 24 2007, 01:25 AM

BHP lysaght (before it got turned to BlueScope Lysaght)

Bluescope is the steel manufacturer

lysaght is the roofing people

now i work full time as hospital's janitor - cleaning up other people's mess

edit: TS : there's no such thing as aluminum wiring - they all use copper wires. aluminum just doesn't make sense in electric conductivity

This post has been edited by lucifah: Sep 24 2007, 03:13 AM

ah... never knew there still are aluminum wirings. tq tq.

i rarely see aluminum wiring nowadays except in bus bars where they are in 1/2" thick plate, 4" wide, carrying 415V and about 600 amp for my hospital

just a piece of info to share



anyhow, back to the main topic: frmo engineering side, yes, zinc roofing tend to be more "flammable" than concrete / clay tiles

however, this is due to one main factor:

WHEN YOU USE METAL ROOFING, YOU'LL NEED TO LAY A LOT OF SOUND PROOFING INSULATION LAYER - usually about 2" of rockwool

this insulation is the fire hazard

without the insulation, you'll be deaf when it rains. it's bloody noisy

This post has been edited by lucifah: Sep 25 2007, 11:30 PM

if you use CONCRETE tiles, you don't need the zinc sheet since it's thick enough and is waterproof

but if you use CLAY tiles, you're gonna need the zinc sheets since water may soak / seep into the house

i have never heard of BOMBA not approving those metal sheet layers yet. anyone can confirm?


anyway, additional info:

CONCRETE tile : cheap, easily available // easily stained, not beautiful (about RM 1 per piece)
CLAY tile: beautiful, the color is lasting and not so susceptible to fungus growth // bloody expensive (RM 2 (china made) to RM 15 (italian tiles) per piece)

nope. it's what ppl may have convinced you

but we engineers try to economize everything - security isn't our priority. cost, safety and customer satisfaction is.

the metal sheet has to be there or else someone will have to use umbrella in the house during rain

never heard of this before, but it shouldn't affect your fire insurance policy since you're not goign to install any sound insulation layer. the metal sheet is there only for waterproofing purposes

i guess you are using clay roof tiles. probably a J-profile tile.


for no.2, read my earlier post. clay tiles needs waterproof layer (in this case, metal sheet is the cheapest and easiest and last longest)

AND REGARDING PITCH ; it doesn't matter what degree your pitch is. it depends on the type of roofing material and profile

if you use seamless metal sheet with klip lok profie, you can go as low as 4(deg)
if you use tiled rooginf, it's recommended to be at 25(deg)
as long as you don't go below 5(deg), you should be ok. lower than that, then consider reinforced concrete flat roof (major headache)

the only reason why pitch is extra important is in 4-season country where high roof pitch is needed so snow won't settle on the roof. snow = extra weight and will make your roof collapse

learn more. roof pitch has nothing to do with sunlight. it's either snow or roof design or just for styling,

for no 3, you still need the chicken wire netting. if not, how will you put the rock wool? u surely needs something to support the rock wool and that's why the chickn netting is there

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Added on September 27, 2007, 1:50 pmthat's what they used to call it. it's more like a generic term. galvanization is kinda old. it's more to "aluminization" nowadays

it's not in coil, but in metal sheet rolls of standard width and infinite length

the roof profile is cold-formed using pressing machine.

This post has been edited by lucifah: Sep 27 2007, 01:55 PM