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Yes, someone has created radiant walls

MarcDelany | Posted in Energy, Heating & Insulation on

This is a reply to Bill, oops looks like really old question came up from google when I was looking for this article: https://www.finehomebuilding.com/2009/10/15/warmboard-as-wall-heater

| Posted in Energy, Heating & Insulation on September 27, 2002 02:53am

Hi,
I’m real new to this, or any forum, this is my 1st.

My long term plan is to replace my forced air system w/ radiant heating.

I live in a cold climate, AC Isn’t a big deal here, maybe 20% of houses have it.

Anyway, my basement ceiling is only 7′ high. Currently, it has heating ducts taking up about 1′ of that, right down the center of the basement, Stupid.

There are already 3 bedrooms and a family room downstairs.

My idea is to tear out the ceilings, about 800Sq.Ft., and put in tubing.

But downstairs, I’m stuck w/ the floor as is, I prefer radiant to radiators, so I plan to put tubing in the lower part of some interior walls. And build a radiant wall.

I’m even thinking of boxing in the bottom 2 ft. or so and filling around the tube w/ pea gravel for thermal mass and better heat transfer. Still can’t decide if this is genius, or taking a simple idea and complicating it beyound all recognition.

Any opinions on a radiant wall as opposed to a radiant floor?

Oh yeah, I intend to put in a manifold w/ 1 loop this year heated by a gas water heater, it has an exchanger, and test out one wall.

Thanks much.

Bill

After fighting my subcontractor to install on the wall, he relented, saying it was my dime…. It worked so well he wrote an article for Finehomebuilding claiming the credit and forgetting he poo-pooed the plan or to credit the designer, Marc Delany:  https://www.finehomebuilding.com/2009/10/15/warmboard-as-wall-heater
 
Walls or floors work just fine if you have enough sq footage. Best to place where nothing is blocking the radiant pathway to what needs to be warm. I usually only go 4′ off the floor on walls to reduce the chance someone will hang a painting and drive a nail through. I don’t always use warmfloor or warm board. It’s easy enough to a create a 2-3 layer sheetrock channel, generally below a chair rail. But I have used the whole wall at times. Use Pex-al-pex 1/2″ tubing and insulate the backside, put a thermostat going to an actuator and manifold in each separate heating zone desired.

Note: If a zone is in a floor and tiled over, remember to create a thermal break “slipjoint” in the tile, or the tile will crack across in anycase. Same might apply to certain situations with wall tile crossing into a different zone.

 
I’ve done over 50 rooms with “warmwall”, in several buildings over the years. In this building in the original article, the heating cost for the 8,000 sq feet on 3 floors went from $800 a month (2006 prices) to $50 a month these past years, in gas. This is in part by using 27 separate compartments or heating zones and with all walls, floors, ceilings now insulated. This building has triple hung single pane windows too. The building was built in 1905 and is a registered national landmark here in Bayside CA.  https://noehill.com/humboldt/nat1985000353.asp
 
Marc Delany

Replies

  1. calvin | | #1

    Thanks.
    A good reason for keeping the forum and its archives.

  2. Oli191 | | #2

    It's so bad it's funny, I mean you had to emphasise with the "Yes" in the title of how crazy this is

    1. MarcDelany | | #3

      Please use all unobstructed "lines of sight" between source and target... Still arguing with HVAC contractors who place heat source at windows (straight out into outside!), that's between people and outdoors.

      Vestiges of fossil fuel folk engineers. Use common sense. Floor (not under cabinets), walls, (not behind cabinets). ceilings, (not over cabinets)... That's the kitchen available area... Radiant heats objects, not air.

      1. calvin | | #4

        ?

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