Not too sure about that one mike
Clause B2 states that :
(b) 15 years if:
(i) Those building elements
(including the building
envelope, exposed plumbing
in the subfloor space, and
in-built chimneys and flues)
are moderately difficult to
access or replace.
Notice the exposed plumbing in sub floor space no mention of enclosed behind wall plumbing.
B2.2 Building materials,
components and construction
methods shall be sufficiently
durable to ensure that the building,
without reconstruction or major
renovation, satisfies the other
functional requirements of this
code throughout the life of the building....and life of building we all know is 50years
reconstruction or major renovation is called ripping walls open to find and fix closed in pipes...when you cut someones gib open to repair pipes it aint no small job to repair it...the bill is 1 the plumber, 2 re-gib, stopping, painting(means the whole wall or room to match the repair) and or tiling or wallpapering it is a major for the home owner to have a leaking pipe behind a closed wall so it has to be a durability of 50 years when looking at the B2 clause
B2.3.1 Building elements must,
with only normal maintenance,
continue to satisfy the performance
requirements of this code for the
lesser of the specified intended life
of the building, if stated, or:
(a) The life of the building, being
not less than 50 years, if:
(i) Those building elements
(including floors, walls, and
fixings) provide structural
stability to the building, or
(ii) Those building elements are
difficult to access or replace, or
(iii) Failure of those building
elements to comply with the
building code would go
undetected during both
normal use and maintenance
of the building.
Here we are looking at 2 & 3 ...pipes behind gib or in enclosed spaces are dificult to access or replace and sometimes as we all know leaking and dripping pipes go undetected for years not being picked up during normal maintiance and use of building and so cause in some cases severe damage to the structure and integeraty of the building.
So i reckon 50year product gurrantee is needed.
my boss has just had a go with the council about getting coc on his house cus of his exposed decking and the councils and housing departments take on this issue is if structual elements have to be removed to access elements behind the cladding to be removed then the material behing said building element must have a durability of the element covering it...For example they count tile decking as part of the structual element of a building and as the tile has a durability of 50yrs then so the waterproffing underneath must have a durability of 50yrs...he had to get the head hancho of the dept of housing up for a colective meeting and during the meeting he said to them so what about buteline and there 20year gurrantee and the housing of dept head said "dont go there it will open up a can of worms"...and thats because buteline does not conform with the building code clause B2...
Haha but thats just my take on it...
Anyone else out there know any more indepth about this subject?