ZEMCH 2015 - International Conference Proceedings | Page 465

Table 4 : DB energy consumption parameters and Passive house requirements .
DB Heating * Cooling * Energy
Annual heating demand ( kWh / m2a )
Heating load ( W / m2 )
Overall space Cooling load ( W / cooling demand m2 )
( kWh / m2a )
Primary Energy ( kWh / m2a )
Energy reduction through renewables ( kWh / m2a )
Consumption parameters
Fulfil Passive house requirements
0 54 65 65 295 -
X
* It is enough when only one of the parameters is fulfilled .
In the DB simulation results , it is observed that the cooling demand got higher due to the solar direct penetration and less heat is lost because of the east and west walls transformed into partition walls . However , the cooling loads considerably decrease and therefore the primary energy consumption as well . After this process the bioclimatic features should be applied in the next steps .
DB1 simulation
The first step during the energy efficiency upgrading stage consists on improving the thermal characteristics of the fabric materials by reducing their U-values and thermal bridges . If the modifications made during this step do not achieve the passive house requirements this model should not be consider as a design option . This study will name the prototype as DB1 in order to examine the full method and be able to generate a comparison table that shows all the modifications made . The prototype will be conceived with the sustainable materials provided by the LP Company ( Table 12 ) ( Figs . 18,19 ).
Table 5 : DB1 building parameters .
Building parameters
Site
Treated floor area TFA ( m2 )
External wall U-value ( W / m2K )
Windows ( including frames ) U-value ( W / m2K )
Roof surface U-value ( W / m2K )
Floor slab U-value ( W / m2K )
Average thermal envelope
DB1 Londrina , Brazil 66.67 0.369 2.556 0.400 1.200 0.886
Figure 18 : DB1 plan , section and heat sources .
Design decision-making process of affordable low energy homes in Latin America 463