DIN 4108
|
DIN 4108 |
|---|---|
| Area | Construction |
| title | Thermal insulation and energy saving in buildings |
| Brief description: | Thermal insulation for buildings |
| Latest edition | several parts, see text |
| ISO | - |
The DIN 4108 Thermal insulation and energy economy in buildings (previously heat insulation in buildings ) is a DIN standard , the requirements for the thermal insulation describes for buildings. The legal requirement in Germany , the Energy Saving Ordinance (EnEV) , refers to this standard several times. The standard makes specifications for winter and summer thermal protection. Part 6 of DIN 4108 will become less important in the medium term, as it is constantly being replaced by DIN V 18599 as a result of amendments to the Energy Saving Ordinance .
scope
The scope of DIN 4108 extends to the planning and execution of common rooms in high-rise buildings, which are intended for normal indoor temperatures (more than 19 ° C), as well as the planning and execution of common rooms in high-rise buildings, which are intended for low internal temperatures (more than 12 ° C and less than 19 ° C). Ancillary rooms belonging to common rooms are to be treated like common rooms. Buildings with normal indoor temperatures include a .:
- Residential buildings
- Office and administration building
- schools
- Hospitals
- Catering building
- Department stores and other commercial stores
- Company buildings with internal temperatures of at least 19 ° C
Parts of the norm
DIN 4108 thermal insulation and energy saving in buildings consists of the following parts:
- DIN 4108-1
- Thermal insulation in building construction; Sizes and units (withdrawn and replaced by DIN EN ISO 7345)
- DIN 4108-2
- Minimum requirements for thermal insulation (edition 2013-02); to avoid condensation and unhygienic indoor air conditions as well as summer heat protection
- DIN 4108-3
- Climate-related moisture protection - requirements, calculation methods and instructions for planning and implementation (edition 2018-10); contains boundary conditions and calculation rules for the Glaser method
- DIN 4108-4
- Thermal and moisture protection rated values (edition 2017-03); contains essential building physics parameters of individual building materials (lambda and My values)
- DIN V 4108-6
- Calculation of the annual heat and energy demand (edition 2003-06, correction 2004-03); contains all the essential calculation rules for determining the heating requirement in residential buildings according to EnEV (for non-residential buildings see DIN V 18599)
- DIN 4108-7
- Airtightness of buildings - requirements, planning and implementation recommendations and examples (edition 2011-01)
- DIN 4108-10
- Application-related requirements for thermal insulation materials - Factory-made thermal insulation materials (Edition 2015-12)
- DIN 4108-11
- Minimum requirements for the durability of adhesive bonds with adhesive tapes and adhesive compounds for the production of airtight layers (edition 2018-11)
- DIN 4108 supplement 1
- Thermal insulation in building construction; Tables of contents; Index (withdrawn)
- DIN 4108 supplement 2
- Thermal bridges - planning and design examples (edition 2019-06)
Calculation method according to DIN 4108
At present, DIN V 4108-6 may only be used for public-law evidence for residential buildings; DIN V 18599 applies to all other buildings.
Calculation of the annual heating requirement
For the calculation of the annual heating requirement according to DIN 4108, the building to be assessed must be measured if no construction drawings are available.
- The volume and from this the usable area to be heated must be determined.
- The heat-transferring enveloping surfaces (outer walls, windows, roof, floor slab, etc.) are to be recorded in terms of their surfaces and differentiated according to their construction. For each component, the construction structures are to be determined and the heat transfer coefficients are to be verified mathematically using the component method. The multiplication by the areas for the respective component results in the amount of transmission heat loss. The component method is explained below.
- The ventilation heat losses result from the multiplication of the volume by a coefficient.
- To calculate the solar gains, the window areas are multiplied by the respective coefficients according to their cardinal points. All-glass facades are only included in the calculation for 2/3.
- The internal heat gains (heat from devices and people in the residential building) result from the multiplication of the heated usable area by a coefficient.
- The balancing of the individual values results in the annual heat demand (annual heat demand = transmission heat loss + ventilation heat loss - solar gains - internal heat gains).
- A recent amendment to DIN 4108 included the heating system in the heat demand calculation, the primary energy demand. The annual heating requirement is then multiplied by the energy consumption figure. The energy expenditure figure results from DIN 4108.
The calculation process is complex, it is a static process that completely excludes user behavior. It is standardized for all of Germany. From EN 12831 , the different standard outside temperatures are taken from the isothermal map or, for cities with more than 20,000 inhabitants, from a table. In this table, the cities are also differentiated according to low wind or strong wind location and thus have an influence on the calculation of the standardized annual heating requirement of the building. For the verification, it does not matter whether the user behaves in an exemplary manner in terms of energy (ventilation, internal temperature around 20 ° C) or not (tilted window, counter-heating with a room temperature of over 22 ° C).
Component method
The component method is a permissible, simple method for verifying thermal insulation for smaller building projects (e.g. loft extensions). It is used to determine the heat transfer coefficient (U-value) for each component . This calculation step is part of the calculation of the annual heating requirement according to DIN 4108 and for DIN V 18599. The calculation method is clear from the example. A ventilated tiled roof with insulation and plasterboard should be demonstrated.
| Item | designation | thickness | Thermal conductivity | Thermal resistance |
|---|---|---|---|---|
| Component layer | m | W / (m K) | m² · K / W | |
| 1 | Heat transfer inside | 0.13 | ||
| 2 | Plasterboard | 0.015 | 0.25 | 0.06 |
| 3 | Layer of air | 0.020 | - | 0.170 |
| 4th | PE film ( vapor barrier ) | 0.005 | ||
| 5 | Thermal insulation (e.g. mineral wool) | 0.240 | 0.045 | 5.333 |
| 6th | Underlay | 0.005 | ||
| 7th | Battens | 0.030 | ||
| 8th | Battens | 0.030 | ||
| 9 | Roof tile | 0.025 | ||
| 10 | Heat transfer outside | 0.04 | ||
| 11 | total | 0.370 | 5.733 | |
| 12 | Heat transfer coefficient | 1: | 5.733 = | 0.174 |
The heat transfer (items 1 and 10) is a specified rated value. It is also required for the dew point calculation. The heat loss results from dividing the thickness by the rated value of the thermal conductivity. The thermal conductivity is defined in DIN 4108-4 or in EN ISO 10456 for the most common building materials. A fixed coefficient must be specified for the air layer (line 3). For the sum of the heat losses (line 11), the reciprocal value must be formed (line 12), this is the U-value or heat transfer coefficient.
In the above example, the requirement for the U-value of 0.174 would be below 0.24 and thus fulfilled, but the rafter part would still have to be calculated and weighted with the insulation compartment. If the gap were 62.5 cm wide, the requirements would then not be met. Through further optimization, the gap could be widened, the insulation thickness increased, or a higher quality insulation material could be used.
Norms
- DIN V 18599 Energetic evaluation of buildings - Calculation of the useful, final and primary energy demand for heating, cooling, ventilation, domestic hot water and lighting - Part 1: General accounting methods, terms, zoning and evaluation of energy sources .
- EN ISO 10456 Building materials and building products - Thermal and moisture-related properties - Tabulated rated values and methods for determining the thermal insulation nominal and rated values .