Selv om der blev etableret visse fælles foranstaltninger i noget af det filantropiske byggeri, der skød frem i 1850’erne og 60’erne, hørte det egentlige kollektivhus det 20. århundrede til: En boligbebyggelse med selvstændige lejligheder, i nogle tilfælde for grupper med særlige boligbehov, med tilknyttede fællesfaciliteter for beboerne. I udgangspunktet centralkøkken med spisesal og restaurant, andre aflastende servicetilbud for den daglige husførelse, daginstitution, indkøbsmuligheder og senere tillige selskabslokaler, gæstehotel, hobbylokaler m.m.
While most of the cooperative housing had central kitchens with dining rooms, some had a number of common facilities such as day-care centres, domestic help and/or modern washers and dryers. Some of the cooperative housing also had a local grocery store for the residents and the surrounding neighbourhood.
The cooperative housing was planned by some of the leading architects of that era and the majority of the flats had a room with a box bed, a small kitchen and an entrance hall; and all the flats had a toilet, a shower, and central heating. There was also a plan which encompassed flats facing out to corridors. The design of the cooperative housing included closed or open courtyards, L-shaped houses, or blocks of flats surrounded by small gardens. Furthermore, it was considered innovative to build residential properties intended for certain social groups that had specific housing requirements. On the housing market, it was particularly troublesome to acquire self-contained flats for single parents with children and elderly women – primarily people from the working class and the lower middle class.
In 1930, the Danish capital, comprised of Copenhagen and Frederiksberg, was on the forefront of housing development compared to the rest of Denmark and internationally. It would also create an important foundation for widespread building construction of cooperative housing in the future. However, this type of housing never really caught on in the ordinary construction business in the 20th century. On the other hand, it succeeded in positioning itself as an essential means of housing especially for both handicapped and elderly people.