What's the meaning

It depends on the locale. Being "old," if it's in a region where the weather turns cold, it could simply mean that the cracks have not been repaired.

If it's in a region where the temperature never drops, it may be designed with permanent openings in the structure.

This is where my example originally came from:

"Chuck a big dod of toilet paper onto the water at the bottom before you start,
thus creating a cushion for the s***. No awkward splash-noises to contend with.
Particularly useful at the GF's parents' house, which is old and open and noise
really travels."

He is describing a way to avoid the awkwardless when

That charming passage aside, it means it has an open floor plan, not a lot of floor-to-ceiling walls that break the space up into small rooms. Sound travels easily because there are fewer walls to contain it. I confess, I can hear people using the toilet in my rather open house. However, one ignores it, pretending to have heard nothing other than whatever was on TV.

Thanks guys~

Grammar Geek I can hear people using the toilet in my rather open house. However, one ignores it, pretending to have heard nothing other than whatever was on TV.

Shades of Archie Bunker!
You're right, Barb. I was having trouble connecting the cracks and the noise. I think I was led astray by the author's putting the "old house" in the same sentence. (T