ZEMCH 2015 - International Conference Proceedings | Page 346
Therefore, the instalation of the finishing boards and the sheathing (OSB) can start at the same
point of the wall panel. The use of the 15x300 centimetres section of cementitious boards required
adjustments in the original panel thickness (13 centimetres). The adjustment resulted in a increase
of the cross section of the studs (initially with 4,4 x 8,9 centimetres) to 4,4 x 11 centimetres. This decision caused an increase in the volume of wood consumed in the system. However, this increase
in consumption of studs volume compensate for the reduction of finishing boards waste that
represents the highest cost in the system.
In the panels with openings (windows and doors), the solution was to apply two cementitious
board sections in submultiples of 300 centimetres to be installed in the areas under (120 x 100
cm) and above (120 x 50 cm) the openings. The use of these boards sections enables to fully use
one board for finishing two areas with openings without resulting in material waste. The boards
installed at the opening sides must receive an apparent seal, as technical manufacturer specifications, for absorption of tensions caused by thermal and hygroscopic movements, and the effect
of loads. The proposed solutions (Figure 5) prevent random cut-offs and reduce the variety of
boards’ formats.
However, the application of this solution resulted in a mismatch in the positioning of the studs
in relation to the sheathing boards since the studs would be visible in the openings areas. TA
change in the positions of structural components (studs and cripple studs) and in the dimensions
of support structural components (headers and double headers) were necessary to allow the adjustment of the boards within the proposed modulation (Figure 10).
Figure 10: Adjusting the dimensions of the panels components
To attend the modulation, the dimensions of opening areas are restricted to variations of 60 and
120 centimetres. However, the commercial windows have these same finished dimensions, which
generate another dimension mismatch due to the space needed for installation. The use of windows with custom dimensions that meet the proposed modulation allow an area increase in the
vertical direction, for lighting and ventilation.
A new quantitative survey was carried aiming at comparing the materials waste in two situations:
the initial and the suggested proposal. The analysis of consumption and materials waste is shown
in Table 3.
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ZEMCH 2015 | International Conference | Bari - Lecce, Italy