StopGap is a simple and cost-effective way of sealing the gaps between wooden floorboards. Simply unroll the "V" shaped plastic and poke it into the gaps with a credit card. With narrow gaps it will just hold itself in place, sealing the draughts and making the gaps look neater into the bargain. Gaps greater than about 5mm will need a blob of silicone on the joists to help to hold it in place. Please note - an average 3.5 metre square room requires 2-3 rolls of StopGap.