I think non-tiling isn't always a bad feature! For example, you can use the spaces for ventilation (If we're imagining houses with non-tiling shapes) and light

I think non-tiling isn't always a bad feature! For example, you can use the spaces for ventilation (If we're imagining houses with non-tiling shapes) and light to shine through. Strictly you can always find complementary shapes to make non-single tiling tiles of course.