Focus on the difference between feasible alternatives (principle )! insulated concrete forms (icf) can be used as a substitute for conventional wood framing in building construction. heating and cooling bills will be about 5050% less than in a similar wood-framed building in upstate new york. an icf home will be approximately 1010% more expensive to construct than a wood-framed home. for a typical 2 comma 2002,200 ftsquared2 home costing $150150 ftsquared2 to construct in upstate new york and costing $220220 per month to heat and cool, how many months does it take for a 2 comma 2002,200 ftsquared2 icf home to pay back its extra construction cost?