Heat Loss Calculations

    Heat Loss Calculations

    Precision Heat Loss Assessments for Accurate Heating Design

    Heating system sizing starts with an accurate heat loss calculation. Aros provides detailed room-by-room and whole-property calculations based on building fabric, dimensions, ventilation and design temperatures. We can work from suitable drawings and specifications or property survey evidence, supporting informed decisions about heat pump and emitter sizing.

    What's Included

    Comprehensive heat loss analysis tailored to your property.

    Room-by-room heat loss calculations
    Whole dwelling heat demand assessment
    Calculations based on architectural drawings (new build & retrofit)
    Calculations based on on-site surveys (existing properties)
    Fabric performance analysis (walls, roof, floors, glazing)
    Ventilation & air change rate assessment
    Design temperature calculations
    Heat pump sizing guidance

    Why It Matters

    Why Accurate Heat Loss Matters

    Incorrect calculations can lead to serious performance issues. Our calculations provide installers and housing providers with reliable, documented data to design systems with confidence.

    Oversized heat pumps — inefficient cycling & higher costs
    Undersized systems — comfort issues in cold weather
    Poor emitter performance
    Compliance failures

    Who This Is For

    Who This Service Is For

    Heat pump installers needing independent design support
    Homeowners wanting unbiased system sizing advice
    Housing providers planning retrofit or new build schemes
    Developers requiring compliant documentation

    We provide clear reports that can be used for design, compliance, and client communication.

    Drawings, new builds and existing homes

    Homeowners planning a new build can supply architectural drawings and fabric specifications. For existing homes, dimensions and evidence of construction, insulation, glazing and ventilation are needed; an on-site survey may be appropriate where these are incomplete.

    Installers can supply complete survey information for desktop calculations. We review the available evidence and identify missing information and assumptions before agreeing the calculation scope.

    Common questions

    Is this the same as the free heat loss estimate?

    No. The free estimate is an initial indication. A professional calculation assesses each room's fabric, dimensions, ventilation and design temperatures to inform heating design.

    Can you calculate heat loss from new-build drawings?

    Yes, where drawings and specifications provide the required information. Send the proposed layout, dimensions and fabric specifications so Aros can review the evidence and scope.

    Can I commission heat loss calculations without a full system design?

    Yes. Heat loss calculations are available as an independent service for homeowners, installers and housing providers.

    Ready to Start?

    Let's get the design right before the install begins.

    Whether you're an installer looking for a technical partner or a homeowner who wants it done properly — we're here to help.