Answer:
DIN EN 1991‑1‑3/NA, Figure NA.1A, shows the snow load zone map of Germany. The exact assignment of snow loads of administrative units, particularly at the edges of the zones, has to be checked with the competent authorities. The German Center of Competence for Construction (DIBt) offers (in German) the table "Categorization of snow load zones according to administrative limits" for each land area on this subject on its website.
For the locations of Snow Load Zone 1 and Snow Load Zone 2 in the North German Plain, it is also necessary to check whether they are within the defined regions in compliance with DIN EN 1991‑1‑3/NA, Section 4.3. In the table "Assignment of snow load zones according to administrative boundaries", the footnote "Nordd. Tiefld."
According to DIN EN 1991‑1‑3 and DIN EN 1991‑1‑3/NA, higher values than those specified in DIN EN 1991‑1‑3 and DIN EN 1991‑1‑3/NA may result for certain layers of Snow Load Zone 3. These locations are displayed in the table of the assignment of snow load zones according to administrative boundaries ("Zuordnung der Schneelastzonen nach Verwaltungsgrenzen").
Furthermore, it is necessary to consider the results of the research project "Spatial analysis of measured snow load data in five districts and their comparison to snow load zone data of DIN 1055‑5:2005 as a pilot study for the revision of the snow load zone map" by the German Meteorological Service (Deutsches Wetterdienst, DWD).
These special rules are also included in the online service by Dlubal Software. The snow load zones with special rules are indicated by an asterisk. The special rule is also displayed as a comment under the snow load zone. Image 01 shows Snow Load Zone 3* for the city of Altenau. For Altenau, it is necessary to consider an increased snow load. This is also shown as a comment.
