Learn Hardcore Icelandic: Stundum er hávaðinn hjá okkur eins mikill og hjá strákunum þegar við spjöllum í borðstofunni. - Sometimes the noise around us is as loud as around the boys when we chat in the dining room.

In Icelandic, the definite form is used more often than in English when talking about something in a specific situation. Here, you’re not talking about noise in general, but the noise that exists at our place at that time.

So:

hávaði = (some) noise, noise in general
hávaðinn = the (specific) noise

Because the sentence is about how loud the noise is at our place, the definite form hávaðinn is natural.

Why is the word order Stundum er hávaðinn hjá okkur and not Stundum hávaðinn er hjá okkur?

Icelandic main clauses usually have the verb in second position (V2 word order), very similar to German and some Scandinavian languages.

In this sentence:

Stundum (Sometimes) = first element
er (is) = verb, must come in second position
hávaðinn (the noise) = subject
hjá okkur (at our place/with us) = prepositional phrase

So the normal Icelandic order is:

Stundum – er – hávaðinn – hjá okkur …

Putting hávaðinn before er in a main clause (Stundum hávaðinn er hjá okkur) would sound wrong to a native speaker.

What does hjá okkur literally mean, and why use hjá here?

Hjá + dative usually means:

at someone’s place
with/among someone (in their company / in their group)
in relation to someone (e.g. “with us it’s different”)

Okkur is the dative plural of við (we), so hjá okkur literally = at/with us.

In this sentence, hjá okkur is best understood as:

“at our place / in our group”

You might be tempted to use með okkur (with us), but:

með okkur focuses more on being together with us,
hjá okkur focuses more on our place / our group / our side of things.

Because we’re comparing how noisy it is at our place vs with the boys, hjá is the natural preposition.

What is the structure eins mikill og doing here, and why not eins mikið og?

Eins … og introduces an “as … as” comparison, just like English:

eins mikill og = as big/much as, as loud as (depending on context)

The key point is that mikill is an adjective that must agree with the noun it describes:

hávaðinn is masculine, singular, nominative
the adjective must match: mikill (masc. nom. sg.)

So:

hávaðinn er eins mikill og … = the noise is as great/loud as …

Mikið is the neuter form or an adverbial form and would not agree with hávaðinn, so eins mikið og would be ungrammatical here.

You could rewrite it more explicitly as:

Stundum er hávaðinn hjá okkur eins mikill og hávaðinn er hjá strákunum.
Sometimes the noise at our place is as loud as the noise is with the boys.

Why is it hjá strákunum and not hjá strákarnir or hjá strákar?

The noun strákur (boy) is declined, and the form here is dative plural definite because of hjá:

Nominative singular: strákur
Nominative plural: strákar
Dative plural indefinite: strákum
Dative plural definite: strákunum (strák- + -un- + -um)

Hjá always takes the dative, and we’re talking about “the boys”, not just boys in general, so we need:

hjá
- dative plural definite → hjá strákunum = at the boys’ place / with the boys

Forms like hjá strákarnir mix dative preposition with a nominative ending, so they are ungrammatical.

Why is there no verb after og hjá strákunum? Shouldn’t it be og hjá strákunum er or og hjá strákunum er hann?

Icelandic often omits repeated words (ellipsis) when the meaning is clear, just like English does.

The full, completely explicit version would be:

Stundum er hávaðinn hjá okkur eins mikill og hávaðinn er hjá strákunum …

But that repeats hávaðinn and er, so in normal speech/writing they are dropped after og:

… eins mikill og (hávaðinn er) hjá strákunum …

English does something similar:

“Sometimes the noise at our place is as loud as (it is) with the boys.”

So the missing er (and hávaðinn) is simply understood from context and doesn’t need to be said.

What does þegar do here, and is the word order þegar við spjöllum always like this?

Þegar introduces a time clause and here means when (in the sense of “whenever we do this / at the times when we do this”).

The clause:

þegar við spjöllum í borðstofunni
= when we chat in the dining room

Inside this subordinate clause, Icelandic uses normal SVO word order (subject–verb–object):

Subject: við (we)
Verb: spjöllum (we chat)
Place phrase: í borðstofunni (in the dining room)

So þegar + [subject] + [verb] + … is the standard pattern, just as in English “when we talk …”.

Why spjöllum and not spjallum? What’s the base verb?

The base verb is að spjalla = to chat.

Conjugation (present tense, indicative):

ég spjalla
þú spjallar
hann/hún/það spjallar
við spjöllum
þið spjallið
þeir/þær/þau spjalla

Notice the u-umlaut in the 1st person plural: a → ö in spjöllum. This is a regular pattern for many -a verbs in Icelandic.

So:

við spjöllum = we chat

How is borðstofunni formed, and why that ending?

The noun is borðstofa = dining room.

Here, we have:

Preposition: í
Situation: location (in), not movement into → dative case
Number: singular
Definiteness: definite (“in the dining room”)

Declension of borðstofa (singular):

Nom.: borðstofa
Acc.: borðstofu
Dat.: borðstofu
Dat. definite: borðstofunni

So:

í
- dative definite singular → í borðstofunni
  = in the dining room

If you said í borðstofu, that would be in a dining room (more indefinite).

Is there a difference between eins mikill og and jafn mikill og in this kind of sentence?

Both are used in “as … as” comparisons, and in many everyday cases they are interchangeable:

eins mikill og
jafn mikill og

In practice:

jafn is a pure adjective/adverb meaning “equal, even, as”,
eins comes from einn (one) and functions as an adverb “equally, as”.

In your sentence, you could also say:

Stundum er hávaðinn hjá okkur jafn mikill og hjá strákunum …

Most speakers would not feel a big difference in meaning here; both sound natural. Some people feel jafn is a bit more “neutral” and eins can sound a touch more colloquial, but both are common and correct.

Why is er singular here and not eru?

The verb er (is) must agree in number with the subject.

The subject is hávaðinn:

hávaðinn = the noise → grammatically singular

Therefore the verb must also be singular:

hávaðinn er … = the noise is …

Using eru (are) would only be correct if the subject were plural, e.g.:

krakkarnir eru í borðstofunni = the kids are in the dining room.