I am adding a second bathroom to my small house. Also extending the master bedroom. Plus 2 walk-in closets. All in all, adding 330 sf to a 1000 sf house. This is in San Diego, so heating isn’t a big deal. Still we need some heat during the winter months. The house (1958 vintage) has a 80, 000 BTUH wall heater that does the living room and kitchen but very little gets back to the bedrooms.
I am hoping to do this addition for aroung $50K, so I don’t want to spend $10K on a central heat system. Also, it is on a slab and has open-beam ceilings so there is no place to hide duct work. I am looking for some cool wall-mounted gas heaters for the bedrooms.
Anyone have some suggestions? Or, another approach?
Rick Barlow
Replies
Check on Rinnai heaters in the web.
Great units.
Do a google on gas wall heaters (furances). Direct vent gas heaters and direct vent gas fireplaces.
A fireplace will can be used both for looks and for a heat source.
Gee, I have a 2300 square foot house on the Canadian border that uses only about 80,000 BTU/hr to keep warm even down to 40° below zero. It's insulated, of course. If you have insulation you have pleanty of heat.
From what I understand your problem, though, is getting it to the addition. If you have to add supplemental heat, you won't need much. I would guess even 10 or 20,000 BTU/hr would be enough, but you'd be wise to have someone do a calculation for you. If your unit is too big it will be very uncomfortable.
You might get by with electric. Your average winter lows are only around 48°F and the record is only about 30°F. Electric is costly to run, but wicked cheap to install.
A heat pump would be more to install but would use much less electricity.
Thanks for the input. Electric heat is not allowed in my town. I am still looking for some gas heaters. The wall heater I have is 26,000 BTUH not 80,000! (My mistake) I still never turn it up past "1" (out of 10) but the heat never gets to the back bedrooms. The Rinnai heaters (ductless) are illegal in California. The smaller Rinnai (229-A) looked to be perfect! Darn! I am looking at the MPI heaters now.
How do you heat your water? If an adequate system, you could pump some hot water to the new area, and kick space or wall coil/blowers would distribute the heat. Actually, easier and less space than ductwork, and you could thermostat the system to send hot water when only needed in the addition. Hope this helps. PaulEnergy Consultant and author of Practical Energy Cost Reduction for the Home
Rinnai also has thru the wall direct vent models available.
If you're still in the planning or early building stages, plan to insulate the #### out of the area, and work agressively to stamp out air infiltration. That'll reduce your heating load significantly, and you can get away with probably just a bathroom heater.
How about a nice gas fireplace? Perfect for a temperate climate, and much more attractive.
I like the fireplace idea if you can find a good location for it that will vent easily.
Does the "...doesn't allow electric heat" rule apply to the electric grids they sell to go under tile floors in bathrooms? This stuff is not meant for primary heat under normal circumstances (like snow country). It's really just for a little extra comfort for bare feet. But in S. California it might be adequate to bump up the temp in that area of the house just the little bit it needs for the rare cold snap. It's not too expensive to buy or operate and there are no gas lines, ducts, boilers, etc to deal with.
Of course, insulate. Assuming they sell insulation in S. California. :-)
The house originally had no insulation whatsoever. Walls, ceiling, none! I have put R13 in the walls from the outside while I was re-siding it. Now, I have put 1 1/2" of iso-foam on the roof before re-roofing.
As far as the firplace idea, I have a brick fireplace in the livingroom. The bedrooms are pretty small to be having an open flame.
I could put electric in the bathroom as long as it wasn't the general heat source.
I am currently thinking of a tankless water heater for DHW (Takagi?) and either the same one or another tankless providing hot water for some baseboard heaters in the bedrooms. The company (Runtal) also makes a cool towel warmer that is a radiator for the bathroom!
We're pouring the slab next week so let's hear your thoughts!
I may not have solutions for you. But I do have a couple of questions and observations:
Is there a building code requirement that requires non-electric heat in every room or is this strictly a personal comfort decision?
How cold does it normally get there and for how long before temps in the 60's return? I ask because temps in the low 60's are all that's needed to maintain something like 72 indoors without any heat at all. After all, there are lots of low level heat sources in a typical home - cooking, HWHeater, people, even light bulbs. If you've got some solar gain potential, it's even better.
Then there's the question of thermal mass. In other words, how long will the house hold a temp when the outside temperature suddenly drops for a couple of days. In our home (only moderately insulated) in snow country, typical spring/fall temp swings of 60's during the day and 40's at night often doesn't require the furnace to kick in at all. Which brings us to the question of insulation.
The level of insulation you mention is minimal at best. Get about 3x the insulation you mention in the attic and make sure you have reasonably energy efficient windows and in all honesty - unless I'm totally ignorant about your climate - you don't need any extra heat at all, except for the bathroom floor electric thing I mentioned before to keep your tootsies warm.
However, if this is a busybody city code issue requiring heat, then you gotta do what you gotta do.
If it was me, I would do the insulation & windows and then forget about the heat. Buy a $30 electric space heater for the 2 nights every year you might need it.
One more thing: Fireplace need not mean open flame. Zero-clearance gas fireplaces (which are almost standard here in new developments) are very safe, even in tight areas, always have glass in front of the flame, have variable output levels, are perfect for occasional use and are easy to install, especially against an outside wall where it is direct vented (no chimney). They are not even that expensive. The only real knock on them (aside from the fake wood inside) is that they are not very energy efficient, but for a few hours a year who cares?
Good luck. Let me know what you decide. I'm curious.
Thanks,
The building code requires me to have some sort of non-electric heat source permanently deployed. The winter temperatures can get down to 40 degrees at night. That lasts for a couple of months. I have friends with houses that are less tight and less insulated than mine that have no heat at all. They may fire up the kitchen oven to warm things up on especially cold mornings.
The existing house has 2 x 4 walls, so that's what I put in the addition. There is no attic. The ceiling is 2 x 6 planks which is the roof decking. I recently put the 1 1/2" of iso-foam over the entire roof. This will be the first time in 45 years that the house has had any roof insulation.
Rick