ᐅ Interior and Exterior Plastering in Winter

Hello everyone, I have a question and hope someone can help. Now that the shell of our house is finished, the plasterers are next. Interior plastering is scheduled to start tomorrow. The weather forecast predicts temperatures between 4 and 5 degrees Celsius (39 to 41°F) for the coming days. At night, temperatures are expected to be around the freezing point, even dropping to minus 5 degrees Celsius (23°F) the day after tomorrow. The construction manager said this wouldn’t be a problem. If the temperatures rise again, the exterior plaster will be applied right afterward. However, a friend told me today that this makes no sense at all. If the interior plaster goes up now, and then the screed is laid, there will be so much moisture inside the house that it won’t be able to escape once the exterior plaster is applied immediately afterward. Besides, he said it must never be colder than 5 degrees Celsius (41°F) during the first days and nights. So, if the exterior plaster is applied this winter, I can be sure to get mold in the house over time. He advised me to wait at least until spring. That sounds reasonable. What do you think?

Your acquaintance is mistaken; cold air can hold a lot of moisture. Especially when the interior walls are plastered, the windows will be closed anyway, so a higher temperature will be maintained inside regardless.

alter0029 schrieb:
A friend told me today that this is complete nonsense. When the interior plaster is applied to the walls and then the screed is laid, there is so much moisture in the house that it cannot escape if the exterior plaster is applied immediately afterward.

Moisture does not escape through the wall itself but is removed by ventilation through open windows. So, the friend is mistaken.

It is also true that drying works very well in winter because cold air is relatively dry.

As long as the processing guidelines of the plaster manufacturer allow the application, I see no problems.

Good evening everyone, I’m trying to make some progress here.

The house is sealed. The interior plaster (gypsum) was applied 4 weeks ago. The screed (cement) was done on the Friday before Christmas. The underfloor heating is not running yet.

However, I want to start drying the house. I’ve already got 2 dehumidifiers and 2 electric heaters with 3.3 kW each, but the heaters are not powerful enough for 130 m² (1,400 sq ft) over two floors. Now to my question...

Am I allowed to use a diesel heater to warm up the house?

Since a gas heater produces condensation, it’s not an option.

If the exhaust gases are vented outside the house, which I assume is the case, you can use a diesel heater. However, 6.6 kW should generally be sufficient. If the temperature rises significantly above 20°C (68°F), the condenser will not work as efficiently.

Knallkörper schrieb:
If the exhaust is vented outside the house, which I assume, you can use a diesel heater. 6.6 kW should actually be sufficient. If it gets significantly above 20°C (68°F), the condenser also doesn’t work as well.

There is no raw exhaust attached. The unit is electrically powered but burns diesel or heating oil.
To my knowledge—please correct me if I’m wrong.