Old PVC windows are to be painted. Please list the necessary steps These steps are as follows:

1) cleaning the plastic with a mixture of a surfactant and ammonia solution and grinding with an abrasive cloth;

2) primed with polyurethane varnish;

3) topcoat with polyurethane varnish.

In addition to polyurethane varnishes, special alkyd varnishes can be used, polymer and 2-k-acrylic. Epoxy varnishes cannot be used because of their chalking. Dispersion varnishes, on the other hand, are too soft for this purpose and not resistant to higher mechanical loads.

Why shouldn't light plastic windows be painted dark??
Plastic windows under a dark coating heat up very intensively. Due to the resulting stresses, the window structure may be damaged.

Please list the steps involved in painting the old plastic roof gutter
These steps are as follows:
1) oczyszczenie tworzywa sztucznego w kąpieli ze środka powierzchniowo czynnego na bazie amoniaku oraz dokładne zeszlifowanie włókniną ścierną;
2) zagruntowanie lakierem dyspersyjnym;
3) pomalowanie nawierzchniowe lakierem dyspersyjnym;
In addition to dispersion varnishes, special alkyd varnishes are also suitable for this purpose, polymer and polyurethane.