Use an approved sleeper layout and the flooring manufacturer’s heat and moisture limits.
Confirm that the exact hardwood is approved for the proposed radiant-heated assembly. Obtain its nail spacing, maximum floor temperature, moisture/relative-humidity requirements and any limits on temperature changes before preparing the heating layout.
The WarmlyYours TempZone sleeper method uses wood strips 1–2 inches wide and 3/8–1/2 inch high, positioned to meet the flooring manufacturer’s fastening pattern. Lay the heating system between the sleepers and embed it in self-leveling cement up to the sleeper tops. After the cement has cured as specified, nail the hardwood into the sleepers only, keeping nails and staples away from heating cables and cold leads.
Use the guide for cable or Flex Roll as appropriate and follow the project SmartPlan. The flooring manufacturer’s limits also govern thermostat setup: retain floor-temperature protection and avoid scheduled setbacks that exceed its permitted temperature swing. A universal “2 degrees per day” rule is not established for all wood products.
Sources: TempZone cable under nailed hardwood guide and TempZone Flex Roll under nailed hardwood guide.
