Radiant Heat Systems (all installation methods)
General Precautions and Recommendations Always use moisture barriers.
Engineered flooring can be successfully applied over in-floor radiant heat. Know the species you intend to use and how it may interact with radiant heat. Not all species are recommended for this installation, choose species highest in stability ratings for this application.
Because of the wide array of systems on the market, each with its own features, please consult with your radiant flooring provider for recommended installation methods. Hydronic systems must include in-floor temperature sensors and an outdoor thermostat that allows the system to adjust the water temperature according to anticipated heat loss. Radiant heat contributes to the drying out of all woods. Use of a humidification system may be required to maintain the proper humidity level. The indoor relative humidity must be maintained between 30-50% year round. Failure to do so can result in edge cupping, squeaking delamination, splintering, or face checking.
Avoid shock to the floor, Before installation, run new systems to dissipate hidden or trapped moisture. During installation, reduce thermostat to 65°F. 48 hours after installation, slowly raise the temperature of the heating system to its preferred operating level over a period of 5 days. The surface temperature of the subfloor must never exceed 85°F in any location. The temperature setting must always remain within 15°F of normal operating level, and should never be turned completely off. Excessive heat, rapid heating,
Page 9 of 10
Form: INSTALL – MAYFLOWER® Engineered Issued: 3/07/2011
and/or failure to maintain humidity levels between 30% and 50% is likely to result in cracking, cupping, squeaking and other forms of floor issues. Slight surface splits (checking), particularly at the ends of planks, should be expected with installations over radiant heat and does not constitute a product failure.
Test for moisture, This procedure must be followed regardless of the time of year.
Prior to installation over radiant heat, moisture testing must be conducted and documented. The moisture content for concrete substrates must not exceed 3.0 lbs. per 1000 square feet in 24 hrs per ASTM 1669-89 (Calcium Chloride Test). Wood subfloors should not exceed 12% using a pin type meter. Do not install the flooring until excess moisture is corrected.
RADIANT INSTALLATIONS Related information can be found on our website “Flooring 101”
(1) When edge-gluing together planks over radiant heat, two separate continuous beads of glue should be applied: one continuous bead applied inside the groove and one continuous bead applied to the top part of the tongue and at all seams to ensure a secure bond with the top and bottom of the tongue. This double-gluing helps to minimize board gaps or separation. Humidity related gapping should be expected and does not constitute a product failure.
(2) When nailing planks over radiant heat ensure that fasteners are holding the flooring without damage to the radiant system.
(3) When fully gluing planks over radiant heat ensure that the adhesives are recommended for this application.
Answered on 5/24/2011 by customer care 2