Should You Heat Your Unfinished Basement?

Researched & Written by Craig

Winter can be lovely. Cosy jumpers, warm coffee, and close friends. But we all know the worst part, don’t we? It’s looking at the damn heating bill!

For heating an unfinished basement, the first priority is insulation. If you have cold floors insulating the basement ceiling will help the most. Once insulated, heating an unfinished basement will warm your whole home. Otherwise it’s not worth the money. Try putting rugs on the ground floor instead.

Some people may think “it’s okay, I’ll just get a bigger heater instead of insulating!” –

Please don’t.

I know insulation is more work than ordering a product from Amazon, but it’s so worth it. Heating a drafty uninsulated basement is the same as burning money for warmth!

 

Why Is My Basement So Cold?

As a tunnel engineer by trade, I’m very familiar with the ground. When it comes to basements, the key thing to note is that temperature is constant when below the ground. While the ground surface might be 90F in summer and 40F in winter, this variation stops once you’re just a little bit underground. In most areas, the underground temperature is probably around 55F (13C) all year round.

If your basement gets extra cold in winter, the walls are likely passing cold heat from the ground surface. In other words, the temperature of the dirt around the basement is likely a constant 55F, but the tops of the basement walls may be freezing cold because they’re so close to the ground surface.

What Is Your Cold Basement Costing You In Heating Bills?

Although hot air rises, a cold basement can be a massive heat loss, causing a big drop in your heating efficiency.

In fact, they often account for around 20% of a home’s total heat loss. Especially if unfinished and uninsulated! To investigate this further, a student from Montana University monitored his heating usage before and after installing insulation in his basement.

The result? A huge 30% saving in his heating bill! If your basement is always very cold during winter, it’s also almost guaranteed that it’s very poorly insulated.

What an amazing return on investment for some insulation materials and a bit of hard work. Source.

This was based on the heating for a whole house of about 1800 sq. ft of living space. The insulation added was just doubling the insulation at the rim joist to R-38, adding 1.5″ polystyrene to the concrete walls then building a 2″ x 4″ inside wall with a bit of further insulation.

The cost doesn’t have to be high at all, either! Energy companies often provide rebates on any insulation supplies you purchase or work you contract. So much so that prices can often end up as negligible, compared to the amount you save on bills.

Contact a local insulation contractor if you want to find out what’s possible in your area. They often have partnerships set up with energy suppliers for this kind of thing! (Renting? Don’t worry – as long as you pay the utilities, you can get a rebate). Find some more info at the ‘Insulation Institute‘.

The bottom line? Insulation is always worth the time and money.

How to Insulate Your Unfinished Basement

Although it may seem intimidating to non-DIYists, insulating a basement doesn’t need to be a complicated task. Generally, all you need to do is add some simple materials to the walls, ceiling, and optionally, floor. In fact, even doing some simple and minor spot-fixes can make a huge difference!

Illustrations below I’ve borrowed them from a great insulation guide over at Natural Resources CanadaBefore performing any work, always fully check and prepare the wall/floor/ceiling prior to installation. Check and seal any drafts, and especially any water leakages. 

Insulating Basement Walls & Floor

Insulating walls is typically done by adding some insulating material to the wall, then creating a simple ‘inner wall’ to sandwich the insulation in. This is typically done using insulation batts, blankets, fills, sprays, or boards.

Each of these have their own advantages and disadvantages, but they’re all miles better than no insulation at all. Generally, I recommend picking up simple batt insulations, combined with either rigid boards or a foam spray if you really want to keep that cold out. Full polyurethane spray foams are especially great for uneven or hard to reach spaces, but you’ll need to hire out a contractor for installation.

A simple batt and board insulation setup. Source: NRC.

Insulating a basement floor is essentially the same as the wall, just rotated. Place your insulating layers atop the concrete slab (polystyrene is a standard option), and then install a new inner floor. There’s some good information on this guide by building science.

Insulating Basement Ceiling

Insulating the ceiling is basically all about insulating the rim joists. This some of the easiest but more effective insulation work you can do for your whole home.

Not sure what a rim joist is? They are the edge panels of your basement’s ceiling. 

The rim joists here have been sprayed with insulation foam. While the walls have been fully insulated with solid materials. Source.

If you want to go all the way, you can go ahead and apply insulation to the full ceiling. This act to seperate your basement from the rest of your home – meaning your floors won’t feel as cold. However, it will also limit any warmth that rises up from the basement, if you heat it.

Spot Fixes

Looking for some quick fixes? Pick up a thermal camera (or just a lit candle) and explore the basement. Seek out extra cold patches, and do some ‘quick fixes’ – ideally with insulating spray. While quite rudimentary, patching up areas of excess cold can go a long way in improving overall warmth.

Finally, while it may be obvious, pay attention to any vents and ducts! These should be closed when you’re looking to keep things warm. They’re also a fairly easy option to swap out for insulated alternatives.

How to Efficiently Heat an Unfinished Basement

You’ve got a few different ways to heat an unfinished basement. As much as I’ve gone on about insulation, that’s actually the first option! If you insulate well enough, you may find that the natural heat is then enough to make your basement and rest of your house habitable.

If you do a miniature insulation project, don’t immediately go spend your money on a heater. Give it a few days, and see what difference the insulation makes. If you’re still cold, then consider..

Modifying your HVAC

This option has the highest up-front cost, but the best effect on your bills (and house price!). By adding a diversion to your furnace and directing it to your basement, you’ll have one of the most efficient ways of heating the room. This should make your overall efficiency better, as you’re losing out on a heat sink and gaining a head source. Doubly important considering the heat will rise throughout your whole home.

Space Heaters

The easiest option, and my forté, are space heaters. These are the easiest hassle-free way to instantly heat your basement and enjoy a warmer home. There’s tons of options out there, so I just want to give you a quick run-through of the different types.

I’ll quickly run through my 3 favorite options for heating an unfinished basement. These are:

  1. Oil-Filled Heaters
  2. Infrared Heaters
  3. Propane Heaters

 

Best Space Heaters for Unfinished Basement

Oil Filled Heaters
Top Recommendation for Basement: PELONIS

My absolute top oil-filled heater recommendation.

Oil-filled heaters are the best option in terms of long-lasting heat.

They do take a while to heat up, but then they’re excellent at maintaining that heat. Normally this is done with an ‘eco’ mode, which uses minimal power to maintain the heat.

Once warm they essentially act like a standard electric space heater. Just using much less power.

In my opinion, they’re ideal for basements because of the cheap, long-lasting heat.

Their controls are also so easy to use. The model that I recommend (above), is packed full of digital settings. You can set your ideal temperature on the thermostat – and then, most importantly you can set a timer to switch off.

Using a timer will save you so much hassle of going down to the basement and turning off the heater later.

Pros Cons
Long lasting heatTakes long to heat up
Great energy efficiency
Digital Thermostats
Remote Control Included

Our Verdict

In my view, oil-filled heaters would be the simplest option for an unfinished basement.

Though they take a while to warm up, their long-lasting and inexpensive heat are ideal.

Plus, the modern controls make models like the above super easy to use. That model’s also got a fantastic design, includes a remote control for easy of use, and is the generally the best oil heater I’ve found.


Want to see more oil-filled heater options? Click to see my full guide to the best models for large space (like basements!).

Infrared Heaters.
Top Recommendation for Basement: COSTWAY

The best option for an infrared tower.

In terms of cheap-to-run heat, infrared is the best option. Hands-down.

Infrared works by heating objects, not the air. Because of the way they work, they need less electricity to provide the same amount of heat.

They’re also perfect for drafty basements. Since they heat objects and not the air, all the heat isn’t gone the second a cold draft blows in.

The main downside of these heaters is you can’t set a target temperature. In a basement, though? Not that big of a deal! Especially if you’re just looking to heat up the rest of the home.

Modern models should also come with timers and eco modes to keep energy usage low and switch off when you want them to.

The model I’ve recommended above is a fantastic tower option, which will easily heat a whole large basement. Many other options are available.

Pros Cons
Heats objects; great for drafty areasHeat fades as soon as heater is off
Super silent
Top for energy efficiency

Our Verdict

If you’re going to be spending time in your basement, infrared could be a great choice.

It’s the best for a drafty location – since you don’t lose the heat due to gusty air. It’s also the cheapest to run thanks to using less electricity.

For overall heat I’d recommend a quality tower model like the one pictured above. You can also get fantastic heaters in the form of wall panels, wall heaters, or even targetted floor heaters!


Want to see more infrared heater options? They’re covered in my ‘Cheapest Electric Heater to Run‘ guide!

Propane Heaters
Top Recommendation for Basement: Mr Heater Range

Like a fireplace.. only portable.

My last recommendation are propane heaters.

Consider these ‘bad-boys’ if you’re needing some extreme levels of heat, or if your unfinished basement is just super drafty.

The link below goes to the ‘Mr Heater’ range, which has 3 levels:

  • 25k BTU
  • 30-80k BTU
  • A whopping 75-200k BTU!

If you need some extreme heat, these heaters are the way to do it. Since they’re powered by propane, they’re super easy to place. No electric socket necessary, so no worries.

However, the one rule is you do need ventilation. Please don’t get one if there’s not plenty of air-flow in your basement!

Pros Cons
HUGE heating powerNeeds ventilation
Doesn't need plugged in
Can be placed anywhere

Our Verdict

I’d recommend propane to anyone with a cold, unfinished basement. It’s probably the only heat form capable of overpowering those kinds of conditions.

Propane itself is cheap to use, and the power of the heaters is just ridiculous. They’re not the most modern – in fact quite rudimentary – but man, do they work!


Looking for more propane heater options? Click that link to our guide to the best ones for garages – which equally applies to basements.

Conclusion

As you may have realised, the answer to basement heating is always “Insulation, Insulation, Insulation!”

It’s boring, but it’s true. Not only insulating your basement, but your attic too. By keeping the heat in, you’ll keep the cold out, and keep your costs down. Then, all you need is the smallest of heat sources to avoid those cold floors.

I’m trying to make this website a great source of information for all homeowners. I hope this article has helped you decide on how to tackle your unfinished basement’s heating challenges. If it’s helped you, please support us by checking out some more of our posts!

Thank you for reading, and have a great day.

-Craig