Focus on the difference between feasible altematives (Principle 2)! Insulated co
ID: 2810771 • Letter: F
Question
Focus on the difference between feasible altematives (Principle 2)! Insulated concrete forms (ICF) can be used as a substitute for conventional wood framing in building construction. Heating and cooling bills will be about 40% less than in a similar wood-framed building in upstate New York. An ICF home will be approximately 20% more expensive to construct than a wood-framed home. For a typical 2,100 ft2 home costing S150 to construct in upstate NewYork and costing $210 per month to heat and cool, how many months does it take for a 2,100 ft2 ICF home to pay back its extra construction cost? It will take months to pay back the extra ICF construction cost through monthly energy savings. (Round to the nearest whole number.)Explanation / Answer
Cost of construction of a conventional wood frame house :
$150 per sqft.
Total Carpet area of house = 2100 sqft
Therefore, total cost of construction = 2100*150
= $315000
Cost of construction of an ICF home :
20% higher than a wooden framed home = 315000 + 20%*315000
= 315000 + 63000
= $378000
Total cost of construction of an ICF home is $378000
Construction cost of an ICF is $378000-315000 = $63000 higher.
Cost of heating and cooling bills = $210 per month
With ICF, the cost would reduce by 40% = 40%*210 = $84.
With $84 per month, extra cost of $63000 for ICF homes needs to be covered.
Therefore, number of months required to pay back the extra cost of ICF homes = 63000/84
= 750 months