Mortgage
Monthly payment from price, down payment, rate and term. Equal or declining instalments.
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Home calculators
A mortgage, rent versus buy, heat, insulation and a water bill.
Rent vs buy
Cash spent on a mortgage plus housing costs versus rent, and a rough equity figure after a chosen number of years.
Open a calculatorRental yield
Gross and net yearly yield from purchase price, rent, vacancy and running costs.
Open a calculatorHeat pump
A year’s space-heat demand from floor area and a rough insulation class, then electricity at a chosen SCOP versus gas.
Open a calculatorCooling load
A first-pass air-con size from floor area and watts per square metre.
Open a calculatorHeating fuel comparison
The same yearly heat in gas, pellet, coal, wood, oil, resistance heat and a heat pump.
Open a calculatorDomestic hot water
Heat and electricity to raise daily litres by a temperature difference, then a running cost.
Open a calculatorHeat loss through a surface
Kilowatt-hours through a wall, window or roof from U, area and ΔT.
Open a calculatorGas bill
A month of gas from cubic metres, a kWh factor, energy price and a fixed fee.
Open a calculatorAppliance cost
Kilowatt-hours and the bill for a device from watts and hours a day.
Open a calculatorWater and sewage
A period bill from cubic metres and the water and sewage prices.
Open a calculatorStandby draw
A year of a device that never quite switches off.
Open a calculatorLED swap
Kilowatt-hours and money saved by swapping a bulb.
Open a calculatorHeating degree days
Season heat from heating degree days and a UA value.
Open a calculatorPaint needed
Litres from wall area, coats and the tin’s m² per litre.
Open a calculatorFlooring
How many packs of floor from room area, waste and the box coverage.
Open a calculatorDew point
The Magnus dew point from indoor or outdoor air temperature and relative humidity.
Open a calculatorWind chill
How cold it feels from air temperature and wind speed.
Open a calculatorWallpaper
How many rolls from wall perimeter, height, roll size and waste.
Open a calculatorConcrete slab
Cubic metres for a rectangular slab, with a waste percent.
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