{ "cavity_wall_insulation": { "unit_cost_per_m2": 18.5 }, "loft_insulation": { "unit_cost_per_m2": 12.0 }, "sloping_ceiling_insulation": { "unit_cost_per_m2": 40.0 }, "flat_roof_insulation": { "unit_cost_per_m2": 60.0 }, "suspended_floor_insulation": { "unit_cost_per_m2": 25.0 }, "solid_floor_insulation": { "unit_cost_per_m2": 45.0 }, "mechanical_ventilation": { "unit_cost_per_m2": 450.0 }, "external_wall_insulation": { "unit_cost_per_m2": 100.0 }, "internal_wall_insulation": { "unit_cost_per_m2": 90.0 }, "double_glazing": { "unit_cost_per_m2": 600.0 }, "secondary_glazing": { "unit_cost_per_m2": 510.0 }, "low_energy_lighting": { "unit_cost_per_m2": 8.0 } }