Suggestion: panel-heater by front door for comfort

[Dreadnaught]

A new idea. In the the latest House-Planning-Help podcast (HPH280), John Bootland (the boss of the Passive House Trust) mentions putting a little radiator near the front door to give a feeling or warmth as you enter.

 

Interesting idea; never heard it mentioned before.

 

Here is the clip (24:35): https://overcast.fm/+NC20Ux5Q/24:35

 

And the podcast: https://www.houseplanninghelp.com/hph280-a-beginners-guide-to-the-passivhaus-standard-with-jon-bootland/ 

 

  

[Jeremy Harris]

Given that you only need this feeling as you walk in, and not all the time (as the house will be at a comfortable temperature) I wonder if there's a way of making a short burst long wavelength IR "illuminator", activated by your approach to the front door?  That way it only needs to be powered for a short time.

[DamonHD]

MIT had a scheme with IR lasers on gimbals that could track each person and make them feel warm.

 

David Mackay and I plotted to have IR radiant heaters come on for a short while as you entered a room, eg while rads had a chance to come up to temperature.

 

Rgds

 

Damon

[Ferdinand]

Is this suggestion a bodge to get over the absence of a real porch - and the threshold being cooled because the interior has been exposed to the outside directly rather than indirectly?

[Temp]

1 hour ago, DamonHD said:

MIT had a scheme with IR lasers on gimbals that could track each person and make them feel warm.

 

 If the scanning actuators fail does it burn a hole through you?

[DamonHD]

Who knows: your last thought might be a vary warm feeling inside?  (I think the lasers were fairly feeble and diffuse.)

 

Rgds

 

Damon

[Jeremy Harris]

Could probably be done with some fairly modest radiant heat sources.  I bought a couple of "UV" (really mainly blue/violet, at ~406nm) floodlights to post-cure resin 3D prints, and these are surprisingly good radiant heat sources.  I need to dig around and find out why, as they don't heat most things, but they definitely feel warm if you place your hand in front of one.  My guess is that the wavelength happens to be one that is absorbed by skin, so making it feel warm.

[dpmiller]

@Jeremy Harris I've noticed this effect with some white LED string christmas lights, you can "feel" the light coming off them...

@Jeremy Harris

[Jeremy Harris]

5 minutes ago, dpmiller said:

@Jeremy Harris I've noticed this effect with some white LED string christmas lights, you can "feel" the light coming off them...

@Jeremy Harris

 

Strange, isn't it? 

 

IIRC, white LEDs use a blue LED that excites a phosphor that glows white, so it may be that there is a fair bit of blue, violet, or may be UV light emitted from them as well.  I know that people with artificial lenses in their eyes can be sensitive to the "blue" light from some white LEDs.