Heat load calculation
Room-by-room heat load calculation per DIN EN 12831 — the basis for every correctly sized system.
Reasons for calculation
Before heating replacement
The right boiler size prevents cycling, wear and unnecessary consumption.
Before heat pump installation
The most common cause of inefficient heat pumps is oversizing — the calculation prevents that.
Before underfloor heating
Pipe spacing and flow temperature derive from the room-by-room load.
Your benefits
Standard-compliant result (DIN EN 12831), usable for planning and funding applications
Room-by-room breakdown — you see where each load applies
The basis for hydraulic balancing
How the calculation is produced
Recording of building data: floor plans, components, windows, insulation standard.
Capture of the standard outdoor temperature for Wiesbaden and the building category.
Calculation of transmission and ventilation heat losses per room.
Documentation of results per room and building.
Derived recommendation: system size, radiator/underfloor heating sizing.
How to prepare
Helpful: floor plans with room dimensions, year of construction, details of window and insulation upgrades and the energy certificate, if available.
Heat load calculation FAQs
Why is the calculation so important?
Because wrongly sized systems run inefficiently forever: oversized heat pumps cycle, undersized boilers never get warm. The calculation is cheap compared to a bad purchase.
Do I need it for an existing heating system too?
For a pure like-for-like boiler swap, experience is sometimes enough — for heat pumps and underfloor heating the standard calculation is clearly recommended.
Does it take long?
With complete documents, usually a few working days to the result.