It seems the trick won't work if you let another sim detonate stuff. It should be the same sim who made the statues. it's a Da Vinci decensdant LTW glitch, I think, since you have to master both sculpting and inventing.
It's wise to place the "detonating" ground well away from the house. having a large lot would be nice. place a few trash piles and the ice statues in the same place and detonate. large trash piles make a blast look like a nuclear explosion. that's cool, yet extremely dangerous if your sim catch fire.