S-externality!

Blame it on the cardboard walls! My room-mate is suffering from a peculiar externality caused by the boisterous lovemaking of the inmates adjoining his bedroom. His light sleep is ruined every alternate night because of noises that apparently seek mercy from the Almighty. I guess suspiciously his irritation may be because of his lack of the same activity in his life. Anyways, being a good-hearted and shy guy, he is averse complaining to them. I told him to slip the following apology of a limerick under their door.

When you have a peaceful neighbour,
Life is like heaven.
But when you make love to your dear,
My night becomes a burden.

He laughed it off. But the question remains. What is the most courteous and efficient way to dispose of this externality?