Radiant Heat systems have become standard practice in today's new home construction and in many renovation projects across the country.
In the late 1940's Copper tubing and Portland based concrete were used to install the first mass produced homes on the east coast.
Within 15 to 20 years however this combination had fallen out of use due to the corrosive nature of the Portland concrete against the copper tubing in the United States.
While the United States Builders stopped using the radiant systems due to the unreliability of the copper tubing, the Europeans and Scandinavians began installing plastic tubing to use for In-Floor / Radiant Heated Floors and Ice melt systems for outdoor use.
In 1968 Thomas Engel, a German engineer, developed a chemical crosslink polyethylene, now known as PEX Tubing. Later, Sweden's Wirsbo Began to manufacture PEX.
Around the same time as the first PEX hit the market, the first commercially available Gypsum products began to show up on the market. Just Like the first Radiant tubing this new product needed much refinement. Though these products had a bad reputation that lasted due to the first few years of low quality and low performance, In the early 1980's Radiant Heat installers began using Gypsum products over there Pex tubing and by the late 1980's Gypsum companies began developing the first Underlayments Specifically designed for use with Radiant Heat.
By the early 1990's a big change took place in the Gypsum Underlayment world, when the first reliable Gypsum Product was introduced by USG called LEVELROCK which is a hydraulic cement product. Since then the Gypsum products began to immediately evolve into highly reliable and usable products with compressive strengths up to (8,000psi) which is significant due to the fact that the closest onsite gypsum mix gypsum concrete from sources other than LEVELROCK max's out at half that. It's no wonder LEVELROCK says "this isn't the same Gypsum Underlayment it's better than ever". And they're right!
As soon as LEVELROCK RH and RH Commercial was introduced by USG to the radiant heat installers, it was an instant success and though it has gone through some upgrades including the first 4500 psi radiant Gypsum available it has become the preferred method of installation for tile, wood and carpet installers across the United States. We attribute this to the fact that these products use less water and are all hydraulic cement so they're surface pull strength is superior to their closest competitor.