Der er varmt i ventesalen, selv om det blæser udenfor.

In Danish, der er is very commonly used to state that a condition exists somewhere:

• Der er varmt i ventesalen = It is warm in the waiting room
• literally, something like there is warm in the waiting room

This is especially natural when you mention a place, such as i ventesalen.

You can also hear det er varmt, especially for general statements like It is warm, but der er varmt often sounds more idiomatic when the sentence is about the atmosphere or conditions in a specific location.

So here, der er is not a literal there in the English sense. It is part of a common Danish pattern for describing conditions.

Because Danish often uses the neuter singular form of the adjective when talking about a general condition or atmosphere.

Compare:

• en varm sal = a warm hall
  Here varm describes the noun sal directly.
• Der er varmt i salen = It is warm in the hall
  Here varmt describes the overall condition, not the noun itself.

This same pattern appears in many common expressions:

• Det er koldt = It is cold
• Her er stille = It is quiet here
• Der er mørkt = It is dark

So varmt is the normal form in this kind of sentence.

Ventesalen is the definite singular form of ventesal.

Breakdown:

• ventesal = waiting room / waiting hall
• ventesalen = the waiting room / the waiting hall

The ending -en is the usual Danish definite article for many common-gender nouns. Instead of putting a separate word like the before the noun, Danish often adds the definite article to the end of the noun.

So:

• en ventesal = a waiting room
• ventesalen = the waiting room

Selv om means although / even though here and introduces a contrast:

• Der er varmt i ventesalen
• selv om det blæser udenfor

So the sentence means that one thing is true despite another thing.

You may also see selvom written as one word. In modern Danish, selvom is very common when it functions as a conjunction meaning although/even though. Many learners will encounter both spellings.

So for practical purposes:

• selv om
• selvom

can both be understood here as although / even though.

The det is a dummy subject, just like English it in weather expressions.

Danish normally wants a subject in a full clause, so with weather verbs you often get:

• Det regner = It is raining
• Det sner = It is snowing
• Det blæser = It is windy / It is blowing

This det does not refer to any specific thing. It is simply required by the structure of the sentence.

Because selv om introduces a subordinate clause, and subordinate clauses normally keep the order:

subject + verb

So:

• selv om det blæser udenfor

not

• selv om blæser det udenfor

In Danish, inversion like blæser det happens mainly in main clauses after another element comes first.

For example:

• I dag blæser det = Today it is windy

But after a subordinating conjunction like selv om, the normal order is:

• selv om det blæser

Yes, there is a difference.

Here, udenfor is an adverb meaning outside:

• det blæser udenfor = it is windy outside

But uden for as two words is often a preposition + object meaning outside of something:

• uden for huset = outside the house

So a useful distinction is:

• udenfor = outside
• uden for + noun = outside of something

In this sentence, there is no following noun, so udenfor is the natural choice.

It depends on the comma system being used in Danish.

The sentence contains a main clause followed by a subordinate clause:

• Der er varmt i ventesalen
• selv om det blæser udenfor

Many writers put a comma before the subordinate clause, as in your sentence. But in modern Danish, depending on the chosen comma style, that comma may be omitted.

So you may see both:

• Der er varmt i ventesalen, selv om det blæser udenfor.
• Der er varmt i ventesalen selv om det blæser udenfor.

Both can occur, depending on punctuation preference and style rules.

It can mean both, depending on context.

Literally, blæser comes from the verb at blæse = to blow. But in weather contexts, det blæser is very often the natural way to say:

• It is windy
• The wind is blowing

So in this sentence, the intended meaning is most likely simply it is windy outside.

Yes. A very common alternative is to put the selv om clause first:

• Selv om det blæser udenfor, er der varmt i ventesalen.

This still means the same thing.

Notice what happens in the main clause after the fronted subordinate clause:

• er der varmt
• not der er varmt

That is because Danish main clauses normally follow the verb-second pattern. When something else comes first, the finite verb moves before the subject.

So these two are both correct:

• Der er varmt i ventesalen, selv om det blæser udenfor.
• Selv om det blæser udenfor, er der varmt i ventesalen.