The fastest thermal rehabilitation intervention is the replacement of the old carpentry. This solution is a work prior to insulating the exterior walls, and by the end of the rehabilitation works, you will be able to enjoy already significant cost reductions with you energy bills.
For the specialists with DMD Window & Door, it is not a complicated project and does not require the construction of scaffolding on the exterior of the building, as the windows are installed from the inside of the house. However, when it comes to the invasiveness of the work, you have all the reasons to be concerned about. Your home will be anything but clean during the windows replacement project and there will be lots of dust and debris you will have to cope with, even if the installation team will take the necessary precautions to keep things as tidy as possible.
There will be drop cloths or plastic wrap on your floor and furniture, which will protect your belongings, but inevitably contribute to the messy aspect of your home during the new windows installation project. Even if you are getting only a few windows replaced in one or two rooms, the mess will likely be carried in other rooms too, as it is difficult to contain dust.
Once the work is over, you will surely want to start a general cleaning.