System costs will vary greatly depending on the installation requirements, control choices, and project size. Simple radiant heat systems in large slabs in temperate zones cost only slightly more than the alternatives. However, if you select the many options and features that radiant can offer your home, the first cost will be higher.
Remember that the principal advantages of radiant are comfort and lower operating costs. You should review your plans and requirements with your installing contractor to get a firm price on a turn-key system.