Heating the finished basement - what have you guys done?

[stee6043]

I could use some advice from the hearth gurus if you're up for it.

My basement remodel project had a birthday last month but I'm happy with the progress. It's taken much, much longer than expected and I've doubled the budget. But whats new? Sounds a lot like my boiler install, actually.

Yesterday I finished the bar area and now I have one last thing I need to wrap up before I finish a few spots of drywall and start paint - HEAT. I'm glad this year has been so cold because it helped me realize how inadequate the HVAC in my basement really is. The finished space is about 700 square feet, walk-out, with 60% or so of the finished space above grade. One big slider and several windows. It currently has (5) registers in the ceiling and (1) cold air return in a central wall. Plenty of air movement but the ceiling supply seems like a no win from the beginning. Anything below head height never really warms up. I'm sure the fact that the carpet is gone is not helping at the moment, but I still feel I have much room for improvement here.

Two weeks ago I was considering throwing electric baseboard down there. Cheap, easy to install but I couldn't come to grips with how they look. We don't have baseboard in our house and the trim downstairs is primarily still in-tact after the remodel. I think baseboard is now out for looks and the fact that my trim would have to be reworked pretty heavily. At this point I've started leaning towards adding two in-wall electric heaters with fans. Cadet Com-Pak Twin's to be exact.

Has anyone had any luck with the in-wall units? I'm thinking about a 4,000W unit in the larger portion of the basement, interior wall blowing toward the exterior wall, and then another 3,000W unit mounted under where the TV will go and blowing toward where the couch/seating will go. Both would be on their own thermostat (not the internal included t-stat). My basement is a bit of a dogleg shape so I don't think I can accommodate the entire space with one unit no matter what I do.

Is 7000W sufficient overkill for 700 +/- square feet? Are these fan driven units any good at providing even heating? What am I missing? The existing heat will remain, what I'm adding is just supplemental. I really want the basement to be 100% comfortable and warm. It's intended to be THE place we hang out once complete. Thanks in advance for any thoughts on this.

 

[stee6043]

Ohh and to address the obvious - I am not planning for hydronic heat in the basement only because I don't run my boiler 100% of the heating season. I start at the end of October +/- and will run it until my 4 cord of wood runs out. I don't want my basement heating solution to only be available when I'm running my boiler. That being said, when the boiler is running my heat demand in the basement, at least for one of the two zones, will be very low.

And from a resale standpoint, who knows if the boiler would go with the house or the seller.

 

[GENECOP]

We install wall mounted electric units often, just did one last week, get a variable load unit, the one we just put in can adjust from 5000- to 8500 , that will give you some FLEXIBILTY. Also include a wall thermostat , in a central location, if you need specifics just ask I will dig out my paperwork...One more thought, electric radiant on the floor, don't know what your floor finish will be but it's an option....

 

[stee6043]

Thanks for the reply, Genecop. Do you have any links for the load adjusting units? I'm currently planning on two t-stats, one for each heater. I looked at in-floor for entertainment only. I'd lose a lot of heat through the slab below and the cost per foot is out-of-this-world compared to more mainstream electric options.

 

[woodgeek]

The formula for heating load is BTU/h = Area*DeltaT/R-value, neglecting air infiltration.

If you have a 20'x35' area, with say 700 sq ft of above ground wall area at R-10, and 20°F outside (DeltaT=70-20), then BTU/h = 700*50/10 = 3500 BTU/h = 1000W. If you had 700 sq ft of below ground (ground temp 40°F on average), uninsulated R-1, then you need 700*30/1 = 21000 BTU/h = 6000W.

Sounds like you have plenty of heat supplied if the walls are insulated, not otherwise.

An uninsulated space with a 7000W heater will not have 'even heat', but an insulated one with a 1000W heater, even in the ceiling, will.

 

[jebatty]

We have 1500 sq ft of basement, mostly below grade but also a walkout. About 600 sq ft is fully finished into two rooms and insulated, installed base board 6' in one room and 4' in the other, wall thermostats. The other 900 sq ft is mostly unfinished and partially insulated, installed a 3000 watt wall/fan unit on a wall thermostat. Although we usually keep the basement quite cool, the electric heat easily maintains comfortable temperatures.

We have SW exposure on the walkout, so a goal for this year is to make a downspout hot air solar collector just for the basement. During the coldest part of winter it certainly will provide some supplemental heat to the electric, but during spring/fall it should be able to provide most of the needed heat to keep the basement comfortable (I hope). I really dislike having to pay for heat when it is free from the sun, and electric heat is costly.

 

[velvetfoot]

I'm surprised with all the wood powered hydronic heat going on, another zone in the basement wouldn't be considered. Or is it for shoulder season? But there's storage, so don't the wood boilers perform okay then?

 

[jebatty]

My hydronic heating is the shop only. House is heated with a wood stove in the living room. Wish the house was heated with the Tarm, but the shop is too far away and across the road to do that.

 

[maple1]

Ohh and to address the obvious - I am not planning for hydronic heat in the basement only because I don't run my boiler 100% of the heating season. I start at the end of October +/- and will run it until my 4 cord of wood runs out. I don't want my basement heating solution to only be available when I'm running my boiler. That being said, when the boiler is running my heat demand in the basement, at least for one of the two zones, will be very low.

And from a resale standpoint, who knows if the boiler would go with the house or the seller.

How is the rest of the house heated after you run out of wood? Sorry if I missed it if already posted.

 

[KB007]

How much do you use the basement? We have ~1800 sqft finished basement, but we're hardly ever down there (these days my re-loading rig is down there so it's usually just me for a few hours). It's about 1/2 below grade and gets no lower than 8C all winter, more often around 10-11C. When I want to go do some re-loading or anything else, I just turn on a space heater (1500W ceramic) and put on some socks. I never have to worry about pipes etc as the temp is always 8C or above.

Buddy of mine has one of the wall heaters in his basement, think it's 4-5kw heating about 450 sqft. It works well for him, but he did say he noticed the difference in his electricity bill when the kids are using the basement a lot.

No room for a wood stove down there?

 

[stee6043]

I'm surprised with all the wood powered hydronic heat going on, another zone in the basement wouldn't be considered. Or is it for shoulder season? But there's storage, so don't the wood boilers perform okay then?

My 4 cord of wood usually only heats my home through the heart of winter. I heat in the shoulder season with natural gas. Hence my need for something non-wood reliant in the basement. If I had the time and space for 6 cord of wood this conversation may be different. But I'd still consider resale value. No wood boiler=no hydronic heat in my house currently. I don't want my basement to be without heat should the boiler go away or the next owners choose not to heat with wood (if I ever sell).

 

[stee6043]

How is the rest of the house heated after you run out of wood? Sorry if I missed it if already posted.

Natural gas forced air is the default setup. My wood heat is accomplished through a water-air HX in the plenum. And the forced air is not doing an acceptable job of heating the basement currently.

 

[stee6043]

How much do you use the basement? We have ~1800 sqft finished basement, but we're hardly ever down there (these days my re-loading rig is down there so it's usually just me for a few hours). It's about 1/2 below grade and gets no lower than 8C all winter, more often around 10-11C. When I want to go do some re-loading or anything else, I just turn on a space heater (1500W ceramic) and put on some socks. I never have to worry about pipes etc as the temp is always 8C or above.

Buddy of mine has one of the wall heaters in his basement, think it's 4-5kw heating about 450 sqft. It works well for him, but he did say he noticed the difference in his electricity bill when the kids are using the basement a lot.

No room for a wood stove down there?

I plan on using the basement quite a lot once done. Rec room for the kids, bar for drinking and a dedicated spot for beer brewing. I suspect it will get used almost every day once we get the kids crap, I mean toys, relocated. I'd like to keep the basement 68-70 full time. Currently it's closer to 60 down there when 70 upstairs. Colder closer to the slider/windows. It is fully insulated.

I had a natural gas stove down there that got removed as part of the remodel. It was in a bad spot and was a bit overpowered to use with any regularity to heat the basement. It was also anything but an "even heat" down there.

I do expect a bump in my electric bill once I go an electric route. But to gain the comfortable use of this space I'm willing to pay a bit.

 

[woodgeek]

can you describe the insulation? Sills airsealed? What are you going to have on the floors?

 

[maple1]

I think my off-the-cuff inclination would be try to use the NG, if you will be using the space that much. Would some re-ducting down there fix things?

 

[velvetfoot]

My hydronic heating is the shop only. House is heated with a wood stove in the living room. Wish the house was heated with the Tarm, but the shop is too far away and across the road to do that.

Ok, I get it now.

 

[Wooden Head]

Natural gas forced air is the default setup. My wood heat is accomplished through a water-air HX in the plenum. And the forced air is not doing an acceptable job of heating the basement currently.

A couple of ideas: 1. Use natural gas in a vented fireplace or space heater. 2. Pellet stove. I'm heating a finished 1200 sq. ft. basement with a quad castile run on the low setting. Nice and toasty.
Gas is less expensive than pellets and much less expensive that electric.

 

[Former Farmer]

I agree with Wooden Head.

 

[Highbeam]

The wall heaters are noisy, be ready for that. I have them as backup heat in all rooms of my house, woodstove is the only "central" heater.

Note that these puppies run on 240 volts but use a three wire conductor so a normal 12/2 romex for a 16 amp heater.

They are a great way to go since they are cheap to install, no cords, no maintenance, no duct losses, and pack a punch. Just be ready for some noise and burnt dust smell the first time you use them each year.

 

[stee6043]

The wall heaters are noisy, be ready for that. I have them as backup heat in all rooms of my house, woodstove is the only "central" heater.

Note that these puppies run on 240 volts but use a three wire conductor so a normal 12/2 romex for a 16 amp heater.

They are a great way to go since they are cheap to install, no cords, no maintenance, no duct losses, and pack a punch. Just be ready for some noise and burnt dust smell the first time you use them each year.

Since mine is intended to be "supplemental" I hope the run cycles would be rather few and far between. But the noise is surely a consideration.

Since these are continuous load I was planning on 30 amp circuits with 10/3 romex, 240V. I believe if I plan for 125% of the load I am just over 20 amps. Better safe than sorry.

Thanks for all the feedback, everybody. Nothing left but to spend the money I guess. The nat gas route really won't work well for me to "maintain" the basement temp without having to be down there.

 

[Highbeam]

Since these are continuous load I was planning on 30 amp circuits with 10/3 romex, 240V. I believe if I plan for 125% of the load I am just over 20 amps. Better safe than sorry.

These things are cheaper and easier to find and deal with if you stick to 20 amp circuits and 16 amp loads. You won't find as many options if you want to max out that 10 gauge with a single heater.

 

[fbelec]

the 4000 watt heater would be .6666 over the 80% code for 12 gauge but can run 12/2 for the 3000 watt no need to run 10/3. 10/2 will work fine and be less expense. as far as 7000 watts total being enough, the electric heat companys give us this formula if using 2x4 construction with 3.5 inch fiberglass insulation square feet x 10 = wattage of heat needed for space. if using 2x6 construction with fiberglass insulation square foot x 7.5 = watts needed for space. and yes agree with expect noise from fans. and good idea to split up the 7000 watts with a dogleg shape.

frank