Cold entryway in split level ranch

Craig Patrizio

My aunt has an early 1970's split level ranch with two-zone hot water baseboard. Each level has its own zone valve with one circulator. The garage circuit is on whenever the boiler is on (a third zone without a valve). The two levels connect via open stairs with the main door on a mezzanine in between the two floors. I installed a folding french door at the very bottom of the stairs to keep the cat in the lower section of the house.

When it is cold outside my aunt feels a draft coming from under the french folding door. The entranceway mezzanine is freezing cold while the lower and upper levels are nice and warm. There is no baseboard on the entranceway mezzanine.

I set both the upper and lower zones at the same temperature to eliminate a draft due to density changes in the air (cold air from upstairs would sink into lower level and lower levels warmer air would rise to upstairs). I noticed a little less draft but not enough to make me happy. The front door was replaced a few years ago because we felt a cold draft come from it. That helped but there is still a draft. A small 1500 watt electric heater placed on the mezzanine raised the temperature from 58F to 67F(as determined by the sensor on the heater). It felt a little warmer but was still cold. Colder than what 67F should feel like. After poking around a little more I realized, with my bare feet, that the tile floor in the mezzanine was ice cold. Ahh.. radiant cooling! The space under the mezzanine is accessible (as it is the only storage space in a split level - no basement)and it was feezing cold. I checked for air ingress from the outside. Nothing. Sealed tight... There is just no heat under the mezzanine which makes the tile floor above very cold.

Ok. By now you're probably saying that I should add some heat to this area.. Insulate a little better, etc.. What is the best way to do this? I was thinking of adding a small amount of heat under the mezzanine and then doing some staple-up to the floor above...maybe putting a 2' section of baseboard in the mezzanine itself as a wash for the door.

Ideas? Thoughts on how to zone it, control it, mix it.. something cool.. something, shall I dare say.. sexy?

Thanks in advance.. you guys have always been a major source of knowledge!

Craig

Mike T., Swampeast MO

Simple and Maybe \"Sexy\"

Two Radiant Engineering Thermofins per joist bay in the entry (assuming 16" joist centers).

PEX in the fin.

Tap the fin into the end of the garage "zone" that runs with the boiler.

Insulate with rigid insulation directly and thickly against the fin.

If still cold in the entry (reasonably likely unless you can also attach fin to the bottom of the stair treads) install baseboard in the entry tapped in as the first part of the garage zone.

Just off-the-top-of-the-head, sight and measurement-unseen ideas.

Craig Patrizio

mixing valve?


Thanks Mike.. The mezzanine is 4'x6'..not a huge amount of radiant surface area.

So, add a small 007 off the garage supply header w/zone valve.. Under the stairs have the short section of baseboard.. and possibly baseboard on the mezzanine run off that circuit.. tap into the supply/return of that leg with a mixing valve and another small circ?

And have the temps controlled how?

Craig

Craig Patrizio

Staedler product

Mike,

Do you have any experience with Staedler? They supposedly have a ready-to-install product that sounds similar to the Radiant Engineering Fins. Which have you used?

Thanks,
Craig

Craig Patrizio

More thought on the subject...

As Mike was saying, tap into the garage circuit with a supply/return with no pump or valve and run the copper/PEX to the underside of the mezzanine. Now this is where I would run this line to a short section of baseboard under the stairs and a short one above on the mezzanine. Would I then be able to tap into the copper/PEX supply/return with a mixing valve and small 007 to have flow through my staple-up? and then adjust the temperature of the floor with the mixing valve? So.. the mezzanine heating will be on whenever the boiler is running.. I would wire the radiant pump (007) to come on when the main boiler pump is running.. and the only temperature control would be the mixing valve? The whole thing would go on and off with the two t-stats upstairs and down.. Am I correct with this thinking?

Thanks again,

Craig

Mike T., Swampeast MO

Have only used Radiant Engineering in theoretical installs under constant circulation. Worked perfectly.

Remember that small entry hall floors can usually have a quite high surface temperature and thus relatively high output. People don't "hang out" there and are almost certain to be wearing shoes.

Since your garage "zone" has heat/flow whenever any other zone calls, it's the closest to constant with the current system. Am making a lot of assumptions here, but I'd presume that it's also relatively under-radiated (being a garage) and that there is plenty of heat left after its baseboard.

If you want to get a better idea of what to expect, measure temperatures in that zone at various positions and in various outdoor conditions. Then get yourself an inexpensive "Rad Pad" (available here at Books & More) and make estimate of surface temp of the entry floor.