MCS 020
Heat pump noise assessment
Works out the sound pressure level at a neighbour's window and whether it clears the permitted development limit.
Calculators
Every answer sets out the figures it used and the MCS document its method comes from, so you can check it against a quotation line by line.
Nothing you type is stored, and every calculator also answers as JSON and over MCP.
Start here
Work out what your house needs
These two run the MCS arithmetic backwards. The advanced calculators below each answer one question about a system somebody has already specified; these start from your house and your bills and arrive at the system that suits it.
What size solar system do I need?
Works out the array a home needs — capacity, panels, battery and what it saves — from a postcode, a roof direction and a year of electricity use.
Work it outWhat size heat pump do I need?
Estimates a house's heat loss and the heat pump that covers it, from a year of gas or oil bills, and says whether a quoted size looks plausible.
Work it outAdvanced calculators
Each of these runs one published MCS method, for one figure on a quotation. A certified installer has to work out the same shade factors, heat losses, flow temperatures and noise levels before signing off a design.
Heat pumps
MIS 3005-D
Room heat loss
Works out one room's design heat loss, the figure a heat pump and its radiators are sized from.
MGD 007
Radiator flow temperature
Works out what flow temperature a radiator needs for its room, and the Heat Emitter Guide star rating that follows.
MIS 3005-D
Hot water demand and cylinder size
Works out a household's daily hot water demand and the cylinder a heat pump needs to meet it.
MCS 007
Heat pump running cost
Compares a year of heating on the current fuel with the same heat from a heat pump.
Solar PV
MIS 3002
Solar PV annual output
Estimates a year of generation from a solar array using the MCS standard estimation method.
MGD 005
Solar PV shade factor
Turns a sunpath assessment into the shade factor an output estimate is multiplied by.
Batteries
MGD 003
Solar PV self-consumption
Estimates how much of a solar system's output a household uses and how much it exports, with and without a battery.