A smooth, flat wall is vital for a good finish on any renovation project. It's extra important if you are planning paint for a final finish, but even under wallpaper small defects can show up.
Most old walls in Budapest are plastered directly onto brick. Drywall (plasterboard) has only been commonly used for around 20 years here.
Local builders like to finish walls with a material called glett which is similar to jointing compound or polyfiller. It is a white powder which, when mixed with water produces a paste which is spread on the walls like all other surface finishes. They will apply a first coat on all walls, leave it to dry for several hours, or a whole day. Then a second coat is applied. After this second coat is dry, the wall is then sanded.
We don't like this approach. We prefer to skim whole walls in the British style, using a gypsum based plaster (glett). It gives a harder, smoother finish and takes less time to apply, and less time to dry.
That said, glett is good for filling small holes and for patching, and where the old wall can be filled and sanded we will use glett. But mostly we prefer to skim old walls to give a new perfect finish.
Another advantage is that skimming walls is predictable. It works 100% of the time - often filling needs repeating, or filler fails to adhere to the substrate.
Most new walls will be build from either steel framing (fenyes) covered in plasterboard (gipszkarton) or using lightweight construction bricks (commonly refered to as Ytong tégla) similar to what would call breeze-blocks in the UK.
Plasterboard surfaces are usually taped, filled with jointing compound (glett) and sanded.
Brickwork is plastered with an undercoat and then finished with gypsum based plaster.
Filling and sanding a wall is definitely within the ability of most DIYers. Superbuild have electric, dust-free sanders which make the process much faster and cleaner, but it's definitely achievable with minimal tools and elbow grease. Skimming whole walls requires a high level of skill and is not something that anyone but the most skilled DIYer should undertake.
If you are thinking about replastering a flat in Budapest then get in touch with us and we'll take a look and advise you on the best technique to get satin smooth walls, ready for decorating.