A piece of plywood that is routed for tubing without aluminum, such as Heatply, will result in lower or inadequate output, much slower response, significantly higher operating water temperatures, resulting higher operating costs and uneven surface temperatures as compared to Ecowarm. Aluminum is 1500 times as conductive as wood and the aluminum layer spreads heat laterally and upward and is an integral reason Ecowarm works so well.
If almost good enough is your standard of performance, then we would recommend the contractor to rout his own boards rather than buy them from a manufacturer. However, there are often conditions where a particular room in a house requires good performance to meet the heat lost or another case where quick response is required or yet another condition of high heat loss where tile or stone is over the radiant plywood system. In this case the lack of aluminum will result in very noticeable hot and cold spots known as stripping.