Section I $-$ Numerical Calculations $(50\%)$

In a residential building project, a value engineering exercise was carried out on the

roofing materials of the clubhouse. It is intended to revise the roofing materials from

composite aluminum roof cladding to $200mm$ thick. grade $C45\frac{D}{20}$ concrete flat roof

with greenery above.

a$.$ Advise the cost implication for the proposed change based on the $BQ$ rates and

assumptions provided below:$-$

Assumptions:

Roof area:

$40m30m=1,200m2$

Steel ratio:

$200k\frac{g}{m}3$

All steel bar required are $16mm$ dia. and below

BQ Rates:

C$45/20$ w$/$p reinforced concrete for suspended slabs; $200mm$ thk$.$ $$1,\frac{400}{m}3$

$16mm$ dia. and below bars; hot rolled deformed high yield $$\frac{10}{k}g$

Swan formwork to soffit of suspended slabs

Swan formwork; edges and breaks in slabs; n$.$e$.300mm$

$$\frac{300}{m}2$

Design, supply and install roof greenery

$$\frac{100}{m}$

Design, supply and install composite aluminum roof cladding

b$.$ After confirmation of adopting reinforced concrete roof with greenery features, the

Structural Engineer further advised that the rebar adopted was revised from $16mm$

diameter to $25mm$ diameter. There is no relevant $BQ$ rates available for rebar

diameter over $25mm.$ Assess the cost implication based on the following

assumptions: $-$

Assumptions:

Wastage of rebar:

Profit and overhead of the contractor:

Cost of rebar $($all diameters$)$:

Total bars required in $kg$ :

Mass of rebar per linear meter:

Productivity for fixing rebar in different dia.

$3\%$

$10\%$

$$3,500/$tonne

same as the weight in $($a$)$

$1\mathrm{.}579kg\frac{16mm}{3\mathrm{.}854}(25$mm$)$

assume the same