Planning tools
Independent reading and planning resources. Check the linked original sources before making decisions.
Window rectangle area
Estimate the area of matching rectangular panes for an enquiry. Final measurements, compatibility and order quantity need professional confirmation.
Width × height × count. No cutting allowance, frame area or shaped panes. Measure only from a safe position.Electricity-use scenario
Use an explicitly assumed constant load and your own applicable tariff. Variable equipment use may need a suitable measured energy record.
W × hours × days ÷ 1000 = kWh; kWh × tariff = energy charge. Excludes fixed charges, time-of-use allocation and other bill components. Enter 30 cents as 0.30.Annual energy-charge comparison
Compare two supplied annual energy figures at the same rate. Keep category, capacity and source assumptions aligned.
Each annual kWh × shared tariff. This arithmetic does not verify your inputs, include purchase costs or forecast a complete bill. Results stay in this page; nothing is submitted.