ᐅ Water Inside the House

On the first day of assembling our house, the roof frame was not completed. During the night, a lot of rain got inside. Water is dripping from the ceilings everywhere. Unfortunately, it rained all day on the second day as well, and it took quite some time to finish the roof frame. We are building a prefabricated house, and I am very concerned that the excessive moisture could damage the wood. Would it be advisable to hire a building inspector?

Yes.

In my opinion, it is generally advisable to have an independent expert involved throughout the entire construction process. We were very thankful for our expert.
During the assembly of our house, it was almost continuously drizzling, but since we had enough time for drying before starting the interior work and it was only the framework at that point (no insulation or anything else yet), our expert was able to give the green light after several inspections and moisture measurements. Without the expert, however, I would have been worried!

The contractor is fully responsible for delivering defect-free construction work. This also includes, if necessary, setting up and maintaining a rain- and storm-proof covering at least until the roof structure is protected from rain by a waterproof underlay or an underdeck board (plus underdeck membrane, depending on roof pitch). A prefabricated wooden house completely soaked by rain can cause severe mold growth in the insulated components and lead to structural damage during further interior work due to moisture that has not dried out completely or dries only very slowly. In your position, I would first order a construction stop and have an inspection carried out. Enclosed and already insulated structures must be checked.