ᐅ Apply exterior plaster at the same time as interior plaster, or wait?

Hello everyone,

we are currently considering how to schedule our plastering work.

Some contractors have told us that the exterior plaster should only be applied a few weeks after the interior plaster, to allow moisture to escape from the masonry (Poroton FZ7/mineral wool insulation). At the same time, some also say that it doesn’t really matter...

Our plan was to have the exterior plaster applied right away to complete the trade. Of course, all installations should be finished by then.

Do you have any experience or recommendations regarding waiting or drying times for exterior plaster?

Interior and exterior plastering are two separate trades. They may only coincide by chance being performed by the same company.

I would agree with that as well.

Our shell is just being completed (49cm T7 block filled with mineral wool).
The interior plaster is scheduled for early August. At first, I planned to follow the usual procedure: screed in October and exterior plaster next year.
However, several people have advised me to plaster this “porous” block before winter. I am even considering doing it before the screed.
In other words: interior plaster – wait 4-6 weeks – exterior plaster – wait 4-6 weeks – screed.
Is that excessive or still sensible? Or, like the original poster, should I do interior and exterior plaster at the same time and the screed later?

Thanks and regards