Doesn't look like it's instanced housing, which is a shame. If I had to guess, participating in the restoration will reward you with a new currency, and rather than Gil to buy plots, that currency will be used in Ishgard; Essentially locking Ishgard housing behind something to help prevent it filling up instantly.

Can't say I'm fond of the Ward being on top of Ishgard though... I was really hoping we'd finally get the final Coerthas Vigil as a Housing Ward; We have Stone Vigil as a dungeon. Steel Vigil for a FATE boss. Dusk Vigil as a second dungeon. We're just missing Coerthas Eastern Highlands Dawn Vigil from 1.0. I think a Housing area in Eastern Highlands would have been far more visually interesting than just a lump of grey bricks... Something like a ski resort area... Perhaps not an entirely snowy zone too, I do miss the 1.0 Coerthas somewhat...