Breakdown of Добро пожаловать в наш новый дом!
дом
house
новый
new
наш
our (наш, наша, наше)
в
in / to (direction)
Questions & Answers about Добро пожаловать в наш новый дом!
How does Добро пожаловать work, and does it change if I'm welcoming multiple people?
Добро пожаловать is a fixed phrase meaning "Welcome!" (literally "kindly visit"). It acts as an infinitive expression, so it never changes form. You use the exact same phrase whether you are welcoming one friend, a group of people, or someone you address formally.
Why do we use в + Accusative case (в наш новый дом) here if there is no verb of motion?
The idea of welcoming someone into a place implies direction or a destination, answering the question "where to?" (куда?). Just like when you use an arrival verb (such as приехать or прийти), this implied motion requires the preposition в followed by the Accusative case.
Wait, doesn't наш новый дом look like it's in the Nominative (dictionary) case?
Yes, it looks identical! For masculine inanimate nouns like дом (and the adjectives and pronouns that describe them, like наш and новый), the Accusative case takes the exact same form as the Nominative case.