Even if the build is good spam makes lag either way, and no one likes it.
I'm really not sure you know what you're talking about.
You won't lag from simply bricks unless you've:
-got a really bad computer
-are making a seriously huge build and building with no regards to the brick count
-are emitter, item, explosion, etc spamming with your bricks
you could make a house that's like, 10000 bricks and not lag with a decent computer. it's really not that much to worry about.
perfect example: (just an impressive build that doesn't worry about brickcount i found surfing gallery)
click-uses enough bricks to have detail
-not enough bricks to cause lag
-looks impressive and detailed