anyone have any heating knowlegde?

[foxtail]

Hi Guys,

I'm trying to find a non biased answer to my question. I figure the electrician would be partial to electric base board and the plumbers to hot water. I took a look at a job today, customer wants their porch rebuilt. Currently there is no heating in the porch, the house is heated with hot water. Porch will be 6x8 insulated 2x6 walls, R-31 in floor and attic. What would be more efficient, electric baseboard heaters or hot water baseboard heaters. If the hot water ties in to the house boiler can you put it on another zone? I live up in Halifax, winter temp is average -15C. I hope I have enough info for a basic answer. Thanks a lot, Peter

PS if you have a recommendation of another avenue to find information let me know, I wasn't able to get too much out of random google searches yet.

[tjbnwi]

Do you have room in the service panel for additional circuits? That will help make some of the decision.

I have hot water heat. It should be fairly easy to add another zone and zone valve. I do not think adding 48 square feet will have an effect on the boiler.

If the piping is exposed to the elements, I would recommend adding anti-freeze to the boiler.

Not sure what your electric rates are , but I think it will be cheeper to run the boiler.

Cost to install a system this size may be the same.

Tom

[Martin Holladay]

Foxtail,
Q. "What would be more efficient, electric baseboard heaters or hot water baseboard heaters?"

A. Electric baseboard, which is 100% efficient; your hot-water system probably has an efficiency between 70% and 85%. But why do you care about efficiency? Electricity is a much more expensive fuel than gas or oil.

Q. "If the hot water ties in to the house boiler can you put it on another zone?"

A. Yes.

[foxtail]

Thanks,

It sounds like it's best just to have the plumber tie into the boiler. The porch's walls and floor will all be exterior surfaces but if the heater is installed on the house wall the plumbing will not have to really be exposed to any exterior area and I would imagine still be alright to not use anti-freeze as it's now still in a warm space.

I appreciate the feedback,
Thanks

[GaryJR]

The boiler is already making hot water so that's the direction I would go, but to be more efficient you need to install cast iron

[philthegreek]

Whatever floor the porch is on, just extend the hydronic heating loop into that room. It isn't of significant size to change the dynamics of that loop or the boiler output. If you want to keep an existing baseboard in place in the original zone loop, just add a couple of venturi tee's and add on.
Trying to run an additional electrical circuit may be problematic. I think you are under insulated for Nova Scotia (I'm assuming that's where you mean), if it was in your profile there would be no guessing ;-)
Also, what is the effective R value for the walls and ceiling?

Phil

[David Meiland]

If you're the contractor, you have to collect information from the plumber and electrician and make a decision as to which type of heating makes the most sense.

In some cases, it would take an electrician very little time to pull in a wire and add a baseboard heater with a thermostat. You then have something that can be used occasionally to supply low demand, has a very low install cost, and won't freeze if it's doesn't get used. If the panel is easily accessible and has space in it, this is a slam dunk for lower install cost.

Compare that to the cost of cutting into a radiant system, adding a circuit, piping it out to the porch, and adding a thermostat line back to the boiler. I'd guess it will cost 3-5 times as much to install hot water.

Anyway, who cares if the plumber and electrician are biased--get their prices and find out what other trades might have to be involved.

Martin is obviously right about efficiency--100% for electric, less for gas/oil. Maybe you're on propane there, which could actually cost more than electric. Without knowing your utility rates, it's hard to determine which will be less expensive to operate.

[worthy]

Let the customer make the choice: hydro equals lower install, likely higher ongoing costs. You can guesstimate the added hydro charge at current rates, 12.651¢ kwh, including fuel rider and cost adjustment mechanism. If the door to the porch is open during the heating season, the porch heaters will only be supplemental.

FWIW, I owned and renoed the c.1928 home below one very cold winter and the uninsulated southfacing porch was surprisingly cosy with no heating. (Heat coming through the uninsulated front brick wall was no doubt partly responsible!)

[dgbldr]

You didn't say what fuels the boiler. Electric, NG, propane? That's pretty fundamental to the question you ask.

[philthegreek]

Dave, there was no mention of radiant in floor heat, just "hot water" which is hydronic. ;-)
If the porch is on front and the panel is in the back of the house, running a separate line could be very problematic, so I think the OP needs to clarify a few things before any real answers can be formulated.

Phil

[David Meiland]

I'm not assuming in floor, it could be radiators, or a combination. I still say he needs to get install prices from his subs, crunch the numbers regarding cost per delivered BTU, and let the owner decide.

[Dancing Dan]

Plus it seems to me usage is an issue. If it's a room that's going to get only occasional use, and is easily closed off from the rest of the house, I'd go for the electric on its own t-stat, as opposed to keeping the room to house temp all the time.

[S.Joisey]

And, you'll have less draftiness, better distributed heat if the heaters are on the exterior walls.

[tjbnwi]

Plus it seems to me usage is an issue. If it's a room that's going to get only occasional use, and is easily closed off from the rest of the house, I'd go for the electric on its own t-stat, as opposed to keeping the room to house temp all the time.

A zone valve on the hydronic loop will do the exact same thing. T-stat in the room controls the valve, valve opens, closes relay to turn on boiler and circulator (if not already on due to a call from another zone). Room heats, t-stat is satisfied, valve closes, boiler and circulator are shut down (unless there is a call from another zone). If the boiler and circulator are on (due to another call) the closed valve limits (most bleed a little past the stem) flow to porch, no heat to porch.

If you do go with electric, no receptacles above the baseboard heater, not allowed by NEC code.

Tom

[jrsavoie]

The number one money saver here is insulation. It all depends on what it takes to get the work.
I'd recomend 2 1/2 lb. closed cell spray foam insulation. And go with whatever heat source the customer wants.

Money spent on insulation now will pay back forever. Long after whatever type of heating system you choose is dead and gone.