ᐅ Are additional costs for lime plaster instead of gypsum plaster realistic?

Hello everyone,

We have received a quote for a turnkey solid construction house. For an additional cost of about €13,300, a two-layer lime plaster would be applied inside instead of the standard gypsum plaster. The first layer would be a base lime plaster, and the topcoat would be a trowel finish plaster with a grain size of 1mm (0.04 inches).
The entire house has a gross volume of 878 m³ (31,000 cubic feet). This type of plaster would be used in all rooms except the utility room, technical room, and pantry, which together amount to about 50 m³ (1,765 cubic feet).

Is there anyone who can estimate whether this additional cost is realistic or significantly overpriced?

Thank you in advance.

Good luck

Counteroffer...
In the utility/technical room, we have lime-cement plaster applied in two layers, with a finishing coat as a float finish, and in all other rooms, gypsum plaster.
Lime-cement was cheaper...
Why do you want to replace gypsum with lime plaster?

Edit: Just noticed you said pure lime plaster, but that should only be slightly more expensive than gypsum plaster and not 15€/m².

I need to correct myself... I just quickly checked, and an additional cost of 10-15€ is reasonable for lime compared to plaster when the surface quality is the same. Our plaster was Q4 back then, while lime-cement was Q2... that definitely makes a significant difference.

Setting the price aside... If you want smooth walls, you’ll need to apply a lime-based fine plaster over them...

For my old apartment, I chose lime plaster...

The silicate paint also cost around 100 euros per 12.5-liter (3.3-gallon) bucket...

@Lumpi_LE Prefers lime because it is said to have better climatic properties.

@sauerland By smooth, do you mean Q3? According to the building specification, the gypsum plaster is at Q2.

Use clay plaster in the living areas and avoid aiming for a perfectly smooth finish to keep the costs under control. The additional charge seems rather high to me.