Compare office and remote commute costs.
A hybrid pattern is compared against the full-office baseline it replaces. Each office day carries a commuting cost; each remote day carries a smaller cost in heating, electricity and coffee made at home. The net saving is the difference, and alongside it sits the figure that people value more highly than the money — the commuting hours recovered, which at 75 minutes a day over two remote days is nearly 115 hours a year.
Hybrid pattern against a full-office baseline
Office cost = office days x round trip x cost per mile x 46; home cost = remote days x daily home cost x 46; saving = five-day office cost - (office + home cost)
Typically 2-4 in additional heating, electricity and hot drinks, rising in winter. It is small relative to a commute but not zero, which is why it belongs in the comparison.
That depends on what they replace. If they become sleep, exercise or family time they are worth a great deal; if they become extra unpaid working hours the benefit is more ambiguous.
No. If hybrid working lets you live further out, both the office cost and the housing cost change together, and that is a much larger calculation than this one.