This is the 16048th most frequent Polish word.
tymczasowe
Temporary.
In this sentence, 'tymczasowa' is an adjective that qualifies the construction, indicating it won't remain this way indefinitely.
Konstrukcja jest tymczasowa, później zostanie zmieniona.
The construction is temporary; it will be changed later.
The word 'tymczasowym' is used here as an adjective to describe the apartment, indicating it is not permanent.
Zamieszkałem w tymczasowym mieszkaniu.
I moved into a temporary apartment.
'Tymczasowe' is used as an adjective here to describe the solution, signifying that it is not intended to last permanently.