The Importance of Heat Loss Calculations When Installing a Heat Pump
Heat pumps are becoming increasingly popular in the UK, to heat homes and buildings efficiently and sustainably. However, for a heat pump system to be effective and accurately sized, it’s critical to have a formal room-by-room heat loss calculation.
A heat loss calculation is the first step when designing and installing an efficient, low-carbon heating system like a heat pump. A room-by-room heat loss calculation determines the amount of heat that is lost from a building and the amount of heating required to maintain a comfortable temperature.
Why is Heat Loss Calculation Important?
Traditional boilers have high-capacity outputs, producing high temperature into the heating system to achieve the desired room temperature. The system will keep you warm but may not be energy efficient.
An accurate heat loss calculation is crucial when designing a low temperature heating system like a heat pump. A heat pump has a lower capacity output, producing a lower temperature to the heating system to achieve the same room temperature so design must be very accurate to ensure the heating system works well. Under sizing results in a system that will not be able to heat the property, causing homeowners to feel cold and uncomfortable. Over-sizing leads to energy waste, increased energy bills, and reduced system efficiency. On the other hand,
Incorrectly sized heat pump and radiator systems is the main reason that you hear stories where people have installed heat pumps, but they don’t properly heat the property, or are expensive to run.
A detailed room by room heat loss calculation provides an accurate view of the property’s total heat loss in watts (W), allowing the correct specification of the heat pump, as well as the required outputs for the heating distribution for each individual room, running at the lowest possible flow temperature. The lower the designed flow temperature of the system, the higher its efficiency, resulting in the lowest possible running costs.
How is a Heat Loss Calculation Performed?
Heat loss calculations used in the sizing of heat pumps and to meet MCS compliance are completed using the calculation process set out by CIBSE (Charted Institute of Building Services Engineers) and the following standards:
- The Domestic Heating Design Guide 2014 and EN 12831.
- The UK standards for MCS MIS 3005.
The following factors are considered in heat loss calculation:
- External Temperature: Lower external temperatures result in more heat loss from the building. Local climate data for the property is used.
- Room temperatures: What room temperature is required for different types of rooms.
- Building Fabric: The construction of walls, floors, roof and windows and the amount of insulation all a crucial role in determining heat loss.
For newbuild or renovation projects, the heat loss calculation can be completed using the architectural plans and construction details. To complete an accurate heat loss calculation for a newbuild or renovation property, we will need the following:
- Architectural floor plans, elevations, and sections where available.
- SAP report and calculations where available.
- U-values and building regulation construction details for the property.
- Details of the planned heating distribution.
The room-by-room heat loss calculation is performed by taking all the measurements of the property off the plan, entering these details alongside the construction details into a specialist software. The software then calculates the heat loss of each room for the property, allowing the designed to then specify the heat pump and distribution system accurately.
For existing properties where a heat pump is being considered, to replace the current heating system, where plans are not available, an onsite property survey is required. On this type of survey, the assessor will measure all the rooms and assess the existing radiators to complete the room-by-room heat loss calculation.
Find out more about heat pump surveys here>
Why is Heat Loss Calculation Important?
Traditional boilers have high-capacity outputs, producing high temperature into the heating system to achieve the desired room temperature. The system will keep you warm but may not be energy efficient.
An accurate heat loss calculation is crucial when designing a low temperature heating system like a heat pump. A heat pump has a lower capacity output, producing a lower temperature to the heating system to achieve the same room temperature so design must be very accurate to ensure the heating system works well. Under sizing results in a system that will not be able to heat the property, causing homeowners to feel cold and uncomfortable. Over-sizing leads to energy waste, increased energy bills, and reduced system efficiency. On the other hand, incorrectly sized heat pumps and radiator systems are the main reason that you hear stories where people have installed heat pumps, but they don’t properly heat the property, or are expensive to run.
A detailed room by room heat loss calculation provides an accurate view of the property’s total heat loss in watts (W), allowing the correct specification of the heat pump, as well as the required outputs for the heating distribution for each individual room, running at the lowest possible flow temperature. The lower the designed flow temperature of the system, the higher its efficiency, resulting in the lowest possible running costs.
Summary
In summary, conducting a room-by-room heat loss calculation is critical to ensure an efficient and high performing heat pump system. By accurately determining the amount of heat required to maintain a comfortable temperature, homeowners can avoid over-sizing or under-sizing their system, leading to energy waste and reduced efficiency.
Abode Heat can produce a room-by-room heat loss calculation for your property. This service starts at £250 + VAT for a heat loss calculation up to 300m2 floor area. (Larger properties subject to additional cost). An average heat pump installation can cost anywhere between £12,000 to £20,000 depending on the system and property, making £250 + VAT a worthwhile investment when considering a heat pump system so you have all the facts to make an informed decision on whether a heat pump is right for your property.
If you would like Abode Heat to complete a fully MCS compliant room-by-room heat loss calculation for your project, please get in touch using the contact page below, or click here for more information.