
CLEANFLUE NI CUSTOMER INFORMATION
Stove Calculators
Room heat-output and permanent-ventilation estimates
Use the two tools below as an early planning guide. They do not replace an appliance manufacturer’s instructions, a heat-loss calculation, an installation survey or Building Control requirements.
HEAT OUTPUT GUIDE
Room size ↔ stove kW
Enter the internal room measurements to estimate the nominal heat output needed.
Length × width × height ÷ 14 = estimated kW
Enter a stove's nominal output to see the approximate room volume it may suit.
Nominal kW × 14 = approximate room volume
Insulation, glazing, outside walls, open-plan areas and desired temperature all affect the correct stove size. A site survey and heat-loss assessment should confirm the final appliance.
NORTHERN IRELAND GUIDANCE
Permanent ventilation
Estimate the minimum equivalent area of permanent ventilation for a closed solid-fuel stove.
A permanent, non-adjustable ventilator is indicated.
This is the vent's certified equivalent free area—not the face size of a grille. Manufacturer instructions take priority where they require more air. Extract fans, direct-air arrangements and unusual installations need an on-site assessment.
One kW per 14 m³
The estimate uses a commonly published rule of thumb: approximately 1 kW of heat for every 14 cubic metres of room volume. It assumes an internal temperature around 21°C when it is 0°C outside. The building itself can move the final requirement up or down.
VIEW HEAT-OUTPUT SOURCE →NI Technical Booklet L
The ventilation result follows Table 3.1 for solid-fuel stoves, cookers and boilers up to 50 kW. Where airtightness is unknown, the lower-permeability route is used, as directed by the booklet. Any larger manufacturer requirement must be followed.
VIEW OFFICIAL NI GUIDANCE →CleanFlue NI can survey the room, chimney and air supply.
We can confirm suitable stove output, ventilation and flue requirements before installation.