Radiant Heat as a retro-fit...good idea? Bad idea?

15 years ago

My sister and her husband just moved into a 1952 Eichler in Palo Alto. They purchased it from, I believe, the estate of the original owner. From the pictures I've seen...it certainly appears to be "original." Interestingly, this early Eichler has baseboard heat. Unfortunately, it also has no A/C--and Palo is having a serious heatwave.

They are in touch with a builder and an architect...but I am wondering if they are getting the best advice. The builder is talking about adding A/C and forced air heat...with all ceiling ducts. (One assumes this is because of the post-and-beam construction of the home.) I get why ceiling ducts for A/C would be great...cold air falls...but seems like a BAD idea for heat. They are planning on re-flooring most of the house. These are my questions:

1)Wouldn't adding radiant heat be a better choice than ceiling ducts?

2)Can radiant heat be done on a room-by-room basis? Or would they need to move out?

3)If they needed to move out...could the A/C be done now, and the heat added later?

4) Does it make more sense to put in newer, more efficient electric baseboard heat? One assumes it would be more efficient...but perhaps baseboards from the 1950's (or perhaps 70's) are as efficient as current baseboards. This is not their "forever" home...they will probably be in this home 3-5 years.

Thanks for your time. I DID try to do a search before I posted...but came up with very little.

melanie

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Comments (4)

ky114
15 years ago
I'll answer the easy question first. No, newer electric baseboard heaters would not be more efficient than old ones. All electric heaters turn electric power into heat at a rate of 100 percent efficiency, so the only chance you have for heat loss is in ductwork (in the case of forced-air systems), but you don't have that with baseboard, so there's no efficiency benefit to new ones. But having said that, in California electric rates are high, so I doubt electric heat is all that inexpensive to run, on a cost per BTU basis, but, then again, the need for heat in the area you're talking about is not great, so you'd just need to look at some past electric bills to see how much they're spending on heat and whether there is much opportunity to save money.

The choice of ceiling ducts is probably an installation issue, and in a retrofit like this ease of installation is a serious concern. Standard practice would say ceiling ducts are not as efficient for heat, but a lot of newer installations use them because heating systems have much more air moving through them than they did years ago, so the warm air coming out of the ceiling vents often reaches the floor and spreads out. I know of several houses with ceiling mounted supply vents, and I have not heard of any serious complaints with them. One nice thing is your furniture placement is easier without floor vents to worry about.

Radiant heat is a nice system for comfort, but it's going to be costly to put in, and you still don't get air conditioning without a separate ducted cooling system.

My suggestion would be a heat pump, unless electric rates there are so high that gas heat would be cheaper -- and they may be.
mjsee
Original Author
15 years ago
Thanks ky114---that all makes good sense. I'll pass the info you shared on to my sister. I'm the one with the spare time to search these answers out...she's trying to unpack. Did I mention that she has THREE boys...ages two, not-quite-four, and seven? And a husband who travels frequently?

Oy.
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garymunson-2008
15 years ago
My suggestion would also be heat pump. I just built using a 13 SEER unit with a heat recovery unit to provide free hot water but that may not be as useful as here in cent fl where the ac runs 75% of the year. My last house had baseboard heat...very comfortable but more suited for the time of cheap energy. The temperature differential between a hot baseboard unit and the cold outside only 6-8" away makes for a lot of heat loss especially in older homes with poor insulation. I replaced that system with a heat pump (and hru) and cut my electric bill greatly.
mjsee
Original Author
15 years ago
I'll pass this info on to my sister. It sounds as if heat pumps are a good choice in moderate climates...and Palo Alto CA should qualify as a moderate climate!

Thanks for taking the time to answer my questions.

melanie

Radiant Heat as a retro-fit...good idea? Bad idea?

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ky114

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Radiant Heat as a retro-fit...good idea? Bad idea?

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