Construction of double garages including installation on a prefabricated house

Hello.

We are owners of an Allkauf Haus prefab house built in 2011. Now we want to have an extension built. It is a double garage with a room above measuring 6 m x 6 m and a flat roof. This is to be constructed using solid building methods. Now my question: Are there any problems or special things to consider when adding an extension to a prefab house? Our contractor believes that such an extension does not cause major problems.

Thank you in advance for your help.

Have a nice holiday.

Hello,

before we decided to build, we also looked at one or two existing properties.

Among these houses was also such a hybrid house - originally constructed as a timber frame prefabricated house and, five years later, extended with a solid construction.

What caught our attention with this property was that both on the outside in the plaster and inside on the wallpaper, there were clearly visible cracks along the entire transition from the timber frame house to the solid extension.

My father-in-law (master carpenter) then strongly advised us against such a "mixed construction," because a wooden house "behaves" differently than a solidly built one, and in his opinion, the formation of cracks would be a bottomless pit.

Therefore, if I were you, I would rather tend to build the extension in the same construction method as the house itself.

Regards,

Dirk