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    Curriculum / Fixed Costs / Module 6

    Envelope before equipment

    Air sealing and insulation return more per dollar than replacing a working furnace, and almost nobody does them in that order.

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    Air sealing and insulation return more per dollar than replacing a working furnace, and almost nobody does them in that order. It runs to roughly 0 words, and it is one of 32 in this course.

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    School of Life Hacks

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