We have a parquet wood block floor on top of concrete in our through lounge. We are thinking about having carpet put down on top of the parquet wood block floor but in relation to the underlay we are not sure if the best practice is to staple the underlay to the wood block or not. So, should the underlay be stapled, and if it should, how should it be stapled? If it doesn't need stapling, why not? The room is only of average size (the house is only a small 3 bed semi). Any advice would be welcome.