Sparrow chicks in roof?

My dad is currently retiling a roof, and has found a sparrow’s nest with young chicks currently inhabiting it. The nest is getting in the way of his work, and he doesn’t want to disturb it as much as causing the parents to abandon their young. I’m aware that moving the nest is against the law, but are there any alternatives? My dad doesn’t want to have these birds die by his hand, as he is a bird lover (he has bird feeders in the garden and whatnot) and would like to see these birds leave the nest. 

We aren't sure how old the chicks are, or how long it will be until they can fledge . If the parents abandon their young, how hard would it be to hand-rear them? I myself wouldn’t like to see a bird that is increasing in rarity die because their home has been disturbed, if only slightly. We haven’t really had to deal with this before, so just asking some questions! Would love to hear something from all of you!