Lexikon - Yearly warmth usage demand
It is a scalar of the "EnEV" to determinate the amount of energy required for the heating of water in a building.
- Yearly primary energy demand
The "EwEV" therewith describes the amount of energy that will be required to cover the heat energy demand for the heating of a building and the heating of water. By measuring the kind of heat plant, it also considers the amount of energy necessary for gain, transformation and distribution of the respective fuels (gas, oil or current) as well as the losses of the heat plant itself, so to say all losses in generating heat. With the "EnEV", the first call for warmth protection in the yearly primary energy demand was made.
- KWH/(m²A)
"Kilowatt hours per square meter and year" is the unit of the warmth and energy demand of a building. It consists of the necessary energy (WKWh) of one year (t a) in the relation to the utility area (AN m²).
- Air tightness
With the "EnEV" it became a basic part of construction work and is defined in "DIN V4108-7" (state regulation). In this, the standards for air tightness of buildings to avoid unnecessary loss of energy were made stricter. Unfortunately, in recent years, damage occurred in houses constructed under these standards. This, however, comes from false execution of orders or wrong behavior in usage. Air tightness prevents the penetration of air from the inside to the outer components and the danger of dew (steam brake). Air tightness is measured with the blower door method.
- Humidity
It is the magnitude of water steam in the air.
It is greatly dependent on the temperature. It is between 0% and 4% volume to the saturation of the air. Humidity is indicated as absolute in gram of steam per cubic meter at g/m³ and as relative, which indicates the proportion of absolute humidity to the maximal humidity for the actual temperature with saturation in per cent. Too high humidity is the cause for unhealthy climate in the building and damage in construction.
