A liner tube for repairing existing pipes is provided. The liner tube is sufficiently flexible to lie substantially flat under its own weight thereby defining an upper portion and a lower portion. The liner tube includes an inner layer, an outer layer disposed around the inner layer, a first intermediate layer disposed between the inner layer and the outer layer, the first intermediate layer being wrapped around the inner layer to overlap itself and define a first overlap portion in the upper portion, and a second intermediate layer disposed between the first intermediate layer and the outer layer, the second intermediate layer being wrapped around the first intermediate layer to overlap itself and define a second overlap portion in the lower portion. The first and second intermediate layers include a porous material and the inner layer includes material substantially impermeable to liquids.