Flyttevasken er ferdig før nøkkeloverleveringen.

Because both nouns are in the definite singular form.

• en flyttevask = a move-out cleaning

• flyttevasken = the move-out cleaning

• en nøkkeloverlevering = a key handover
• nøkkeloverleveringen = the key handover

In Norwegian, instead of usually putting a separate word for the in front of the noun, you often add the definiteness to the end of the noun.

Because Norwegian uses compound nouns very freely.

So:

• flytte + vask → flyttevask
• nøkkel + overlevering → nøkkeloverlevering

English often writes these as separate words or with a hyphen, but Norwegian normally makes them into a single word.

This is extremely common in Norwegian, so it is worth getting used to reading long nouns as smaller parts joined together.

Not quite. Flyttevask usually means the thorough cleaning done when moving out of a home.

So it is more specific than just:

• vask = washing/cleaning
• rengjøring = cleaning

Flyttevask has the special sense of a cleaning connected with moving house or handing over a property.

Er ferdig means is finished, is complete, or is done.

So:

• Flyttevasken er ferdig = The move-out cleaning is finished

Here, ferdig is an adjective, and er is the present tense of å være.

A useful contrast:

• er ferdig = is finished
• blir ferdig = gets finished / will be finished
• gjør ferdig = finishes / gets something ready

Før means before.

It introduces a time relationship:

• før nøkkeloverleveringen = before the key handover

So the sentence says that the cleaning is complete earlier than the handover.

A learner may confuse før with innen:

• før = before
• innen = by / within / no later than

So før nøkkeloverleveringen means strictly before the handover, while innen nøkkeloverleveringen would not sound natural here.

This is the normal Norwegian word order for a simple statement:

• subject
  • verb
    • complement/adverbial

So here:

• Flyttevasken = subject
• er = verb
• ferdig = complement
• før nøkkeloverleveringen = time phrase

It is very similar to English in this sentence.

Yes. You can say:

• Før nøkkeloverleveringen er flyttevasken ferdig.

That is also grammatical.

But notice the word order: when a time phrase comes first, the finite verb still comes in the second position:

• Før nøkkeloverleveringen
  • er
    • flyttevasken
      • ferdig

This is an important Norwegian rule often called V2 word order.

Because Norwegian usually marks definiteness on the noun itself.

Compare:

• en nøkkeloverlevering = a key handover
• nøkkeloverleveringen = the key handover

and

• en flyttevask = a move-out cleaning
• flyttevasken = the move-out cleaning

English uses a separate article (the), but Norwegian often adds the ending instead.

By itself, it is mainly a statement of fact:

• Flyttevasken er ferdig før nøkkeloverleveringen.
• The move-out cleaning is finished before the key handover.

If you want to express a requirement or obligation more clearly, Norwegian often adds a modal:

• Flyttevasken må være ferdig før nøkkeloverleveringen.
• The move-out cleaning must be finished before the key handover.

So the original sentence sounds more neutral and factual.

The base noun is nøkkeloverlevering.

You can break it down like this:

• nøkkel = key
• overlevering = handover / delivery

Then the definite singular ending gives:

• nøkkeloverleveringen = the key handover

This kind of layering is very normal in Norwegian: first a compound noun, then a definite ending.

Yes, definitely. It helps you recognize how the noun changes.

For this sentence, useful forms are:

• en flyttevask → flyttevasken
• en nøkkeloverlevering → nøkkeloverleveringen

Learning nouns with their article is a very good habit in Norwegian, because it helps with gender and with forming the definite form correctly.