D-A-CH TAGUNG 2011 - SGEB

multi-family houses, group housing and apartment blocks. A further comparison can be seen in[29], which splits the data between East and West Germany, also using year of construction andliving area (sqm.). There are a large number of aggregated databases available for Germany forbuilding year. Collating these for the Northern Rhine area and making some assumptions, thebuilding year was determined for residential buildings. It can be seen that the two World Warsplayed a major role and the reconstruction post-Second World War is characterised in manycities by apartment block and multi-family homes in monotonic reinforced concrete ormasonry.Table 2: Combination age of buildings for particular settlement types P1-P5 as distributed over theDIN4149: German Seismic Construction Type changes% of Buildings pre-1919 1919-1948 1948-1981 1981-2005 post-2005P1 (300000 people) 9 14 57 16 4Using [32], it is found that in the Netherlands, the housing stock has 25% pre-1946buildings, 20% built between 1946 and 1965 and 55% built after 1965. This is very comparableto that of Germany; thus the same percentages will be used. In the Netherlands, 68% ofresidential buildings are single family homes, with 32% of residential buildings beingapartment blocks.In Belgium, [33] finds that approximately 35% of the housing stock is built pre-1945, 54%is built between 1945 and 1980 and approximately 11% is built post-1981.Converting the extra building since then, this equates to about 32% pre-1945, 52% 1945-1980 and 16% post-1981, which is approximately the same as in Germany. A higher percentageof residential buildings are single family homes (approximately 78.5%), with only 21.5% beingapartments [33]. Therefore, using a combination of this data, the building type percentages inthe Northern Rhine Area can be derived.Table 3: The relative population and building percentages of seven common types of German buildingtypes.% Population Living in % of BuildingsPopulation Class P1 P2 P3 P4 P5 P1 P2 P3 P4 P5Country houses or farms 60 30 10 5 0 81.2 55.7 30.3 22.2 0.0One or two family houses 30 50 40 20 10 17.4 39.8 51.9 38.0 27.9Row houses 0 1 2 3.5 5 0.0 0.6 1.8 4.7 9.8Terrace houses 0 1 3 5 7 0.0 0.6 2.7 6.7 13.7More family homes 10 17 38 53 63 1.4 3.2 11.5 23.5 41.0Block houses 0 1 5 10 10 0.0 0.2 1.5 4.4 6.5High rise buildings 0 0 2 3.5 5 0.0 0.0 0.2 0.6 1.2The study of [29] includes building cost data for Western Germany. Data up to 2000 showedthe residential building cost at €1254/m 2 in North Rhine-Westphalia. In addition, studies havebeen done on INFAS data by [34] for the whole of Germany. Adding the construction costindex trends for Germany up to 2010 in Western Germany and a combination of GDP data, thefollowing construction cost data has been found. [14] shows this data.186