Few constructions, such as wells, outhouses or other peripheral buildings, which can be used for macrofossil analysis, have been excavated from Icelandic Viking age or medieval settlement sites. This is in opposite to many excavated settlements in Scandinavia. Therefore, a common sampling environment in Iceland is from former house floors, which means special taphonomical problems and limited use in interpretation and a risk of redeposition and human interference on the cultural layer caused by human activities inside the house. During the period 2000 to 2006 subfossil insect remains have been analysed from house floor samples from several localities and former settlements from Viking age long houses, medieval turf houses and from later historical house remnants. One of the aims is to analyse the fossil insect remains, primarily beetles, for possible interpretation of the environmental conditions, the relation between a settlement and its surrounding nature, the indoor environment of the buildings and to compare the different settlements. The majority of samples from house floors from Iceland are generally poor in fossil insect remains with a domination of beetles originating from the surrounding environment probably used in the building material, reflecting the natural environment and the building phase. But there is some variation. In house floor samples from the 18th and 19th centuries the typical secondary use of abandoned houses as stables is obvious and in the early medieval settlement at Keldur there was a floor of waste within the medieval house representing a period when a part of the house had been used as smithy or for metal work. One of the difficulties with house floor samples is the degree of preservation and content of fossil remains. This is totally dependent on the house history, e.g. its location in the landscape and the material used during its construction, the function of the house or activities in different rooms and finally the abandonment history of the house. But the floor sample usually provides a high preservation degree and high organic content in the sediment. From a taphonomical point of view it is also important to identify parts of the subfossil insect that is connected to different parts of the building and building material, like roof material or the turf used for the walls.