Ceiling joist span question

We're building a 20x30 foot apartment inside the shop we're getting ready to build. Plan to use the space above the apartment as a storage area. Not a lot of interior walls so ceiling will pretty much be clear span.

Talking with my brother, he recommended engineered trusses for the span to better hold the weight. Contractor sent me a quote for the trusses and one for 2x12 joists. I'm not planning to store a ton of weight up there or anything but I do want to be able to use that space.

There's a cost difference, but I'd rather do it right the first time.

What says the THF braintrust?

On a clear span of 20 ft I would go truss.
Look up wood span tables. 2x12 - 12" oc for 20 ft span, truss ? Oc. by mfg.

I would go with engineered trusses but No1- 2x12 are rated for 21’ span at a 30lb/Sf live load.

Your lumber yard should have an engineer that can tell you your options. TGI's may be a good option.

Why can't you beam at mid point of the 30' and joist out either way?

Excellent point. This is why I don't build things for a living. There's a wall at almost midpoint of the 30' width. Could make that load bearing and have 14ft span and a 16 ft span. Seems more doable with lumber instead of trusses.

In our camp house we have a 30x40 building finished inside a metal building. We put up a beam across the middle sandwiched 3 2x12's with staggered seams and 2 evenly spaced post supports underneath.

https://bct.eco.umass.edu/publications/articles/understanding-loads-and-using-span-tables/
Thought it was interesting in the reading it said 2x10's on 24 inch centers provide more stability than 2x8's on 16 inch centers. Interesting stuff.

I built a 24x36 garage twenty years back. I have one 40’ engineered beam for the ridge beam and a 22’ beam for the garage door. 2x10 joists on 24” centers with 3/4” plywood for attic floor. Attic is loaded up heavy. One big room, no center support. Held up fine so far.