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How To Use Pex Pipes For Radiant Floor Heating

How To Use Pex Pipes For Radiant Floor Heating

With traditional pipe systems typically being quite heavy and rigid, often homeowners choose to use Pex pipes when laying down radiant floor heating. PEX tubing has actually been gaining popularity among DIY radiant floor heating fans for the past couple of years. For connecting systems within radiant heating applications, traditional pipe systems frequently need open flames, unlike Plex. Plus traditional materials often need professional equipment to cut and connect which can be expensive and time-consuming.

Here are some crucial points to consider when using and installing PEX pipes for radiant floor heating.

Before Pouring A Concrete Slab- How To Use Pex

  1. When planning your home's construction, discuss the requirements for insulation under the concrete slab. The amount of insulation needed will vary depending on the size and thickness of the slab, the required R-value, and the local water table. If you need insulating assistance, it’s always best to contact the radiant heating system's manufacturer.

  2. Install the specified insulation material in the quantity advised by the manufacturer.

  3. On top of the insulation, place PEX. The tubing is run down one wall, then it is curved to follow the next wall, and finally, it is curved again to follow the wall that is opposite from where you started. To secure the tube to the insulation, staple it across. The PEX tubing should not be punctured. As an alternative, if the rebar is already in place, secure the tubing to the rebar using wire ties, preferably at every curve.

  4. As you wind the tubing back toward where you started, curve it into a 6- to 8-inch arc and start making a series of elongated "S" shapes. Continually tie or staple the tubing. When everything is finished, there should be two PEX tubing open ends next to one another in a corner of the room.

  5. Set up a concrete slab by having a contractor pour concrete over the PEX tubing. To enable installers to connect the system to the heat source, make sure the two open ends protrude from the slab. The hydronic system cannot radiate adequately unless the concrete is at least two inches thick.

Subfloors With Channeled Plywood

  1. Attach sheets of plywood with unique grooves to the current subfloor using nails. The channels or grooves are made specifically to accommodate PEX tubing and to keep the PEX below the level of the radiant floor. Drive nails into the joists below by first going through the channeled plywood and the subfloor.

  2. The PEX tubing should be inserted into the grooves in an "S" configuration. To make it simpler for the installer to connect PEX tubing to the heat source, you should finish in the same corner of the room where you started.

  3. Using a trowel, spread a thin layer of thin-set to fully enclose the PEX tubing. It is advisable to give the thinset at least 24 hours to dry before adding finished flooring materials, such as cork, tile, or laminates.

  4. Easy to install, inexpensive, and continuous uniform heating - it’s easy to see why PEX is such a popular choice for radiant floor heating.


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