Radiant Heat Dry Above | Radiant Floor Heat Staple Up

Infloor radiant heating in a low mass system means a heating system that is either dry above or dry below. This means there is no concrete. The response time of a dry system is faster than that of a high mass system. The different types of common low mass systems are a staple up, a dry above system, and a ultrafin.

Infloor Radiant heat using a staple system

Infloor heat that is stapled up to the bottom of the floor form the floor below is called a staple up system. The pex pipe is held to the underside of the floor by stapling the heat transfer plates to the floor. These plates will let the pex sit inside the space provided and hold the pex tight to the floor at the same time.

Heat transfer plates will conduct the heat from the pex and evenly disperse the heat through the area of the floor that the plate covers. This is a much better use of heat transfer than trying to just use the pex pipe.

This system is best installed during new construction or if a home is being completely gutted. The largest downfall to this system is that is someone does work on the floor above that requires penetrating through the floor there is a good chance that piercing of the pex will take place. These could include installing a sub floor for tile or adding hardwood after the home is finished. The staples in the hardwood will penetrate through the floor. I have seen applications where the hardwood people were supposed to use shorter staples, and still hit the pex.

Radiant heating using Dry Above

This is great for a retrofit. The object here is to build sleepers (8 inch strips of ¾ plywood) and install them on the floor with spacers in between that will allow for the pex. The spacers have two clips that will hold the pex into place. Between each spacer should be a heat transfer plate. These plates are approximately 24 inches in length. At the end of every other sleeper will be an end bend. This allows easy turning of the pex to go in the next direction. There is two slots for the pex to go into if need be. So you have a few options on directions.

This way of installing infloor heat is great if the house is already finished. This system is also very easy to install requiring only one person if need be.

The downfall to this system is that you lose an inch or so of space, meaning that your doors will have to be cut to size. Laying the sleepers in place and figuring out the layout of the pex pipe can be time intensive.

I personally believe this infloor heating system is the best way of getting radiant heat into a finished home. There will be some drywall damage as you will need to get your supply and return mains for each header back to the boiler. But compared to the cost of this luxurious heating system and new floors, repairing and patching a little drywall will only work out to under 5% of the job.

Radiant Heat using ultrafin

This is the newest of radiant heating system. When using ultrafins the pex will be installed in the joists at an interval of about 24 inches. This is easiest done during new construction, or during a major renovation.

The pex pipe will run perpendicular to the joists and through the center. Then after you have installed the pex you will install fins onto the pex with a rivet holding the fin to the pex. The pex will transfer heat to the fins just like in baseboard heat. The fins will radiate heat in all directions and the insulation you install below the fins will ensure that the heat all radiates up to the floor. The insulation that is installed is reflective insulation.

This is the only infloor heating systems that I have not installed. (There are others, but they are not in the mainstream. And I feel that the size of the pex that is used is to small for proper heating. Just my opinion.)