NCC 10.8.4 · 2025

Condensation Management Calculator

Enter building length, answer the question on the base of the roof and choose eave or fascia venting and the calculator will determine your requirements.

What is the length of the building in metres?

In metres.

m

Is the area of the base of the roof under 10 m²?

YesNo

Select option below for eave or fascia venting

Aluminium Eave Vent Twin PackAEV2040W(open area 21,000mm² per vent)Aluminium Fascia Vent Twin PackAEV1260xx(open area 21,590mm² per vent)

1. Building length
2. Base of the roof
3. Vent

High level

-

Eave level

-

Use this calculator for every section of roof. If the roof has several sections, use the calculator multiple times.