Thanks to Laura for this Frugal Baby Tip!
Is your baby waking up because of the wet feeling in the diaper? Have you considered obtaining some brushed polyester liners? They keep the skin a bit drier than just cotton against it.
The other thing you could try if you don't have any of those is to use some of the polypropyllene liners that you buy from any drug store. These are not flushable, but if you just used them at night, and used about 4 of them one on top of the other, it would keep his skin a lot drier. If you sew, before you've ever washed any of them, you could pile 4 layers of them together and, using a polyester thread overlock them all together so that you don't have to mess about with it at diaper time.
If you use the polypropyllene liners, they'll wash up very well indeed so you can use them again and again.