Module 02

Heat Loss Calculator - Simplified PN-EN 12831 Methodology

Heat loss calculations based on simplified PN-EN 12831 methodology. Fast results, full transparency.

Heat loss calculations based on simplified PN-EN 12831 methodology. See every wall layer, every U-value, the split between transmission and ventilation losses. Everything is visible, nothing is hidden. Results in minutes, not hours.

Why heat loss calculations matter now

Since March 2025, a heat loss calculation (OZC) is mandatory when applying for the Czyste Powietrze (Clean Air) programme. It's Poland's largest home-renovation subsidy, offering up to 170,000 PLN. Without the calculations there is no application. Your clients need it.

Until now, the calculations meant expensive desktop software (990-18,000 PLN in licences) or outsourcing to an engineer (500-1,500 PLN per project). Small installation companies had no good option. They either paid up or lost the job.

Installers who can produce heat loss calculations themselves win on every front: they are faster than the competition, retain full control over the result, and keep the entire fee. It is a concrete advantage in every client conversation.

How to calculate heat losses

01

Enter building data

Provide dimensions, location, and climate zone. The system fills in sensible defaults. Change only what differs from the typical case.

02

Define building elements

Add wall layers, windows, and doors. Pick a ready-made preset for a typical construction or define your own layer by layer.

03

Automatic calculations

The system instantly computes transmission losses, ventilation losses, and thermal bridges using simplified PN-EN 12831 methodology. Every step is visible.

04

Generate a PDF report

The report contains full calculations. Ready to hand to the client and use for initial assessment when applying for a subsidy.

Simplified PN-EN 12831 methodology

Calculations based on simplified Polish standard methodology. Transmission, ventilation, thermal bridges. You see every step.

Every wall layer visible

See the wall composition layer by layer: thickness, lambda, U-value. Nothing is hidden.

Minutes, not hours

Simple forms with sensible defaults. You can go deep (non-uniform walls, custom layers), but you do not have to.

Useful for Clean Air grants

Since March 2025, heat loss calculations are required for the Czyste Powietrze (Clean Air) subsidy (up to 170,000 PLN). HeatAlgo helps with initial building assessment.

Transmission / ventilation split

See exactly how much heat the building loses through walls (transmission) and how much through ventilation. Helps with solution selection.

PDF report

Professional report with full calculations. For the client, for the grant application, for the documentation.

Ready-made construction presets

Typical walls, windows, and doors are already in the system. Pick from the list. No need to know lambda values by heart.

PDF export in one click

Report with full calculations, ready to print and hand to the client.

HeatAlgo vs traditional software

Comparison of tools for heat loss calculations

Price

HeatAlgo

Free (beta)

Traditional software

990-18,000 PLN

Installation

HeatAlgo

Browser

Traditional software

PC (Windows)

Training

HeatAlgo

None

Traditional software

Weeks

Methodology

HeatAlgo

Simplified PN-EN 12831

Traditional software

Varies

Transparency

HeatAlgo

Every step visible

Traditional software

Often a black box

PDF report

HeatAlgo

Yes, simple and readable

Traditional software

Yes, complex

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