Learn Farsi: حتی سقف مستحکم هم فرو ریخت.

The word hattâ is placed right before the phrase you want to emphasize, which is saghf-e mostahkam (the sturdy roof). To complete this emphasis, Farsi typically frames the focused phrase by adding ham immediately after it. While the sentence could technically make sense without ham, using this hattâ ... ham pair is the most natural and structurally complete way to express 'even X' in Farsi.

Could ham be placed at the very end of the sentence instead?

No, its placement here is strict because it forms a pair with hattâ. When used as an emphatic frame, ham must come immediately after the specific noun phrase being focused on. Moving it after the verb foro rikht would break this grammatical frame and sound unnatural.

The verb rikht usually means 'spilled' or 'poured'. How does adding foro make it mean 'collapsed'?

The word foro is a directional prefix meaning 'down' or 'inward'. When combined with the base verb rikhtan (to pour or spill), the compound verb foro rikhtan vividly describes something losing its structural integrity and falling down in a heap. This is the standard verb for buildings, walls, or roofs collapsing.

Is there an ezafe vowel linking mostahkam to ham?

No, there is no ezafe before . There is an linking the noun to its adjective, making it (sturdy roof). But is a separate grammatical particle, not a modifier of the roof. You simply say , without any linking vowel connecting the adjective to the particle.