Szkoda majątkowa jest poważna.

You are right that in everyday Polish, adjectives often come before the noun, for example duży dom (a big house).

But in more formal, legal, technical, or fixed expressions, the adjective can come after the noun.
So szkoda majątkowa is a set phrase meaning property damage / material loss.

This post-noun position often sounds more official or classificatory, as if the noun is being assigned to a category:

• szkoda majątkowa = property damage
• odpowiedzialność cywilna = civil liability
• prawo karne = criminal law

So here, szkoda majątkowa is best understood as a standard legal-type term, not just a random noun + adjective combination.

Because szkoda is a feminine noun in Polish.

Polish adjectives must agree with the noun in:

• gender
• number
• case

Since szkoda is:

• feminine
• singular
• nominative

the adjective must also be feminine singular nominative:

• poważna

Compare:

• poważny problem = a serious problem (masculine)
• poważna szkoda = serious damage/loss (feminine)
• poważne zagrożenie = a serious threat (neuter)

All the main words here are in the nominative singular.

Breakdown:

• szkoda — nominative singular
• majątkowa — nominative singular feminine, matching szkoda
• jest — verb to be, 3rd person singular present
• poważna — nominative singular feminine, describing szkoda

This is a basic X is Y sentence:

• Szkoda majątkowa = the subject
• jest poważna = is serious

So the nominative is used because szkoda majątkowa is the subject of the sentence.

Yes — it is the same form, but used differently.

Szkoda can mean:

1. damage / harm / loss
2. a pity / a shame

Examples:

• Szkoda majątkowa jest poważna. = Property damage is serious.
• Szkoda, że nie przyszedłeś. = It's a pity that you didn't come.

How do you tell which meaning it has?
You tell from the context.

In your sentence, szkoda majątkowa is clearly a legal/economic phrase, so it means damage/loss, not pity.

Majątkowa comes from majątek, which means property, assets, or estate.

So szkoda majątkowa means damage concerning someone’s property or financial assets — in other words, property damage or material loss.

This contrasts with things like:

• szkoda niemajątkowa = non-property damage
• krzywda = harm in a more emotional/personal sense
• szkoda na osobie = bodily/personal injury

So majątkowa is not just wealth-related in a casual sense; in this kind of context it is a formal label meaning something like property-related.

It is natural, but it sounds formal and somewhat legal/administrative.

A Polish speaker would expect this kind of wording in:

• legal texts
• insurance documents
• court decisions
• formal reports

In casual speech, people might say something more everyday, depending on context, for example:

• Straty są poważne. = The losses are serious.
• Uszkodzenia są duże. = The damage is extensive.
• To poważna szkoda. = This is serious damage / a serious loss.

So the sentence is correct and natural, but stylistically it belongs more to formal Polish.

In Polish, the verb być (to be) is normally not omitted in ordinary present-tense statements like this one.

So:

• Szkoda majątkowa jest poważna. = correct

You generally cannot just say:

• Szkoda majątkowa poważna. = not standard as a full neutral sentence

Polish does sometimes omit to be in special styles, such as:

• headlines
• notes
• very colloquial shorthand
• poetic language

But in normal standard prose, jest is the expected form.

Yes, Polish word order is flexible, although not every version sounds equally neutral.

The most neutral order here is:

• Szkoda majątkowa jest poważna.

Other possibilities include:

• Poważna jest szkoda majątkowa.
• Szkoda majątkowa poważna jest. — grammatical, but marked and unusual
• Jest poważna szkoda majątkowa. — possible in certain contexts, but less neutral

Changing word order usually changes:

• emphasis
• style
• information structure

So for learners, the original sentence is the safest standard version.

That sentence is also possible, but it means something slightly different in structure.

• Szkoda majątkowa jest poważna. = Property damage is serious.
• To jest poważna szkoda majątkowa. = This is serious property damage.

The version with to points to something specific, as if identifying or presenting it:

• To jest... = This is...

Your original sentence is a general statement about the subject szkoda majątkowa.
The to jest version is more demonstrative and context-dependent.

A rough pronunciation guide for an English speaker:

• Szkoda ≈ SHKO-da
• majątkowa ≈ ma-YONT-KO-va
• jest ≈ yest
• poważna ≈ po-VAZH-na

A few helpful sound notes:

• sz sounds like English sh
• j sounds like English y
• ą is a nasal vowel; before t in majątkowa, it often sounds roughly like on or ont
• ż sounds like the s in measure

A rough full version:

• SHKO-da ma-YONT-KO-va yest po-VAZH-na

Poważna is a good and natural choice for serious here.

Depending on context, Polish might also use:

• znaczna = considerable, substantial
• duża = large
• istotna = significant
• dotkliwa = severe, painful/burdensome in effect

Nuance:

• poważna szkoda = serious damage/loss
• znaczna szkoda = substantial damage/loss
• duża szkoda = large damage/loss, more general
• istotna szkoda = significant damage/loss

So poważna works well, especially if the focus is on the gravity of the damage rather than just size.

The dictionary forms are:

• szkoda → szkoda
• majątkowa → majątkowy
• jest → from być (to be)
• poważna → poważny

So if you look them up in a dictionary, the adjectives will usually appear in the masculine singular form:

• majątkowy
• poważny

But in the sentence they change to match the feminine noun szkoda:

• majątkowa
• poważna