Nadat die loodgieter die pyp herstel het, was die vloer weer droog.

Nadat means after when it introduces a whole clause:

• Nadat die loodgieter die pyp herstel het = After the plumber repaired the pipe

Use na before a noun or noun phrase, not before a full clause:

• na die herstel = after the repair

So a good shortcut is:

• nadat
  • clause
• na
  • noun

Because nadat is a subordinating conjunction. In Afrikaans, a subordinating conjunction pushes the finite verb to the end of the clause.

Compare:

• Main clause: Die loodgieter het die pyp herstel.
• Subordinate clause: nadat die loodgieter die pyp herstel het

So the normal het position changes because the clause is introduced by nadat.

Afrikaans main clauses follow the verb-second rule. That means the finite verb comes second in the clause.

Here, the whole nadat-clause takes the first position:

• Nadat die loodgieter die pyp herstel het, ...

So the next element must be the finite verb of the main clause:

• was die vloer weer droog

If you put the main clause first, it becomes the more familiar order:

• Die vloer was weer droog nadat die loodgieter die pyp herstel het.

Because herstel has the inseparable prefix her-. In Afrikaans, verbs with prefixes such as be-, her-, ont-, and ver- usually do not take ge- in the past participle.

So:

• infinitive: herstel
• past participle: herstel

That is why Afrikaans says:

• het herstel

not

• het geherstel

In Afrikaans, many past actions are expressed with het + a past participle. So het is acting as an auxiliary verb here.

• die loodgieter ... herstel het = the plumber repaired / had repaired ...

So het is not really have in the everyday sense here. It is helping form the past tense.

By contrast, was in the main clause is the past tense of wees:

• was = was

Weer usually means again.

So:

• weer droog = dry again

It shows that the floor had been dry before, then became wet, and later returned to being dry.

Depending on context, weer can also feel like back to a previous state.

Because droog is used after the verb was. In that position, Afrikaans adjectives usually stay in their basic form.

• Die vloer was droog.

But before a noun, the adjective often changes form:

• die droë vloer

So:

• droog = predicative use, after the verb
• droë = attributive use, before the noun

Afrikaans uses die as the definite article for basically all nouns, regardless of gender.

So:

• die loodgieter = the plumber
• die pyp = the pipe
• die vloer = the floor

This is much simpler than languages that have different articles for masculine, feminine, and neuter nouns.

Yes. Loodgieter is a compound noun, and Afrikaans uses compounds very often.

It is one single word meaning plumber. A learner should get used to seeing long single-word nouns in Afrikaans, because that is very common.

So do not try to split it in normal writing; loodgieter is the standard form.

With wees (to be), Afrikaans often uses the simple past was very naturally:

• Die vloer was weer droog.

A form with gewees can exist in some contexts, but here was is the normal and idiomatic choice.

So this sentence sounds natural exactly as written.

Yes. You can also say:

• Die vloer was weer droog nadat die loodgieter die pyp herstel het.

That is also correct. The difference is mostly one of focus:

• starting with Nadat ... highlights the sequence of events
• starting with Die vloer was ... highlights the result first

Both are natural Afrikaans.