Thermal performance modelling

Real-world energy performance test

The thermal performance test uses real measurements of internal temperature and energy consumption. Readings can come from existing smart home systems or from discreet sensors placed around the house.

Lots of Supported Devices

We support input temperature data from a wide range of sensors as well as basic CSV upload.

Smart Meter Data

Electricity and gas consumption data from SMETS 1 and SMETS 2 smart meters can be uploaded.

On-site Generation

The energy generation from solar PV or other on-site generation can be taken into account.

EV Charging

Any electricity used to charge electric vehicles can be discounted for accurate results.

Boiler Lookup

The efficiency of the boiler or heating system can be automatically retrieved from our database.

Energy Model Compatible

The HTC result is a standard metric that can be used as an input into SAP and other energy models.

Compatible with sensors and smart technologies from:

Input building information and measurement data

The more information that is provided, the more accurate the thermal performance test and heat loss calculation will be.

Required building information:
  • Location (postcode or latitude and longitude)
  • Floor area
Optional building information:
  • Built form
  • Attachment
  • Party wall area
  • Boiler winter seasonal efficiency
  • Window dimensions and orientation
  • Glazing type, overshading and frame type
  • Number of occupants
Required measurement data:
  • Internal temperature readings from a single location
  • Energy consumption at service meter (smart meter data or manual meter readings)
Optional measurement data:
  • Internal temperature in up to 10 locations
  • Internal relative humidity in up to 10 locations
  • Half hourly smart meter data
  • Disaggregated heat input for space heating
  • Disaggregated heat input for water heating
  • Local external temperature
  • Local global solar irradiance
  • Metabolic gains

Output performance metrics

Once a thermal performance test has been performed, various metrics relating to the energy performance and total fabric heat loss of the building will be displayed.

Heat Transfer Coefficient, HTC (W/K)
This is the measured HTC value for the monitored period, the lower the number the better. It is specific to building and conditions at the time. If you make energy efficiency improvements, you should see a decrease in the HTC.
Confidence Interval, CI (W/K)
The confidence interval is a measure of uncertainty that the HTC is presented to. The more data that is supplied, the higher the accuracy of the HTC and the lower the confidence interval will be.
Heat Loss Parameter, HLP (W/m²K)
The Heat Loss Parameter (HLP) is a normalised value that enables different buildings to be compared. The HLP gives a measure the thermal performance per usable space, but it is related to the built form as well as the actual performance of the fabric.
HLP Rating
The HLP rating is an indication of the thermal performance of the building based on a scale from Excellent to Poor.
Mean Temperatures
The mean internal temperature, external temperature and temperature difference that were used in the calculation result.

SmartHTC Downloads

PDF Document

SmartHTC Brochure

Summary of SmartHTC features, how it works and technical specification.