Basements are usually cool year-round—comfortably so in summer, a bit chilly in winter. Basements are often partially insulated by the ground around them, so your existing heating system should provide the moderate amount of heat needed for comfortable temperatures. It's always a good idea, though, to make your basement even more energy-efficient by wrapping walls in insulation with R-10 to R-19 values.
Your current cooling system probably does a sufficient job of keeping the basement comfortable during the hottest summer days. If you're having difficulty keeping a walk-out basement cool in summer, consult a heating and cooling contractor to determine whether you need a more powerful cooling system. You also could consider supplementing the current system with a window air-conditioner.
Many basements in homes cooled and heated by forced air already have the ductwork necessary to distribute the warmed or cooled air. If not, a technician can install ductwork relatively simply and inexpensively because a furnace is usually located on the lower level. Still, your basement may need a supplemental heat source. If you have a walk-out basement with large, unshaded, south-facing windows, you may need supplemental cooling as well.
If modifying or expanding the main heating and cooling system in your home is impractical, you still have options. In fact, some of the products listed may prove more efficient, especially if you won't be using your new space constantly.
- Electric heaters of all kinds are usually the easiest and least costly to install but are the most expensive to operate. Electric heat still can be an efficient and comfortable solution, however, especially if you live in a mild climate, heat only sporadically, or heat only a small area.
- Baseboard heaters are 4 or 6 feet long and operate on normal household electrical current; plug them into a wall outlet or hardwire them to an electrical circuit. Baseboard heaters are quiet and easy to conceal, but again, they're costly and ineffective in larger areas.
- Electric wall heaters feature built-in fans to distribute heat and are small enough to fit in confined spaces, such as bathrooms. Because of the fans, wall heaters distribute heat faster but make some noise. They also must be hardwired into your home's circuits. Consider furniture placement when you locate a wall heater to avoid blocking the fan.
- Portable heaters come in several varieties: radiant heaters, which produce instant warmth; oil-filled radiators, which produce a quiet, even heat; and ceramic heaters, which are powerful yet compact. These heaters allow you to heat just the area you're using and are an efficient way to keep comfortable if you don't use your new space for long periods of time. The newest ceramic heaters use an electronic temperature control to smoothly vary the output of both the heating element and a very quiet fan. Their small size and ability to hold a constant temperature without cycling on and off make these units popular. Be sure to purchase only a new heater and look for one that has an oxygen-depletion sensor, which will automatically shut off the unit before building up a hazardous atmosphere.
- Direct-vent gas heaters are efficient, quiet, thermostatically controlled units that provide plenty of clean heat. They're designed to heat a room's air and then distribute the heated air with a fan. A pipe exits the rear of the appliance and penetrates an exterior wall to vent exhaust gases and draw combustion air into the appliance.
Beyond traditional heating systems, you can consider other options, such as fireplaces, to make your basement a warm, dry, and more welcoming place. A fireplace not only makes a room more inviting, but when chosen wisely, can make it warmer during cold seasons.
Most wood-burning fireplaces suck more hot air out of a room than they produce, so these fireplaces are valued more for their ambience. Airtight, wood-burning stoves—some that allow you to see the fire—can be a great way to heat your space, especially if you have a good source of wood to burn. They require lighting, stoking, ash cleaning, and the carrying in and out of messy fuel, though, so they're not for everyone.
Direct-Vent Gas Fireplaces
These allow you to see the flames and be warmed by their radiant heat. Some include a fan to distribute warmed air, making them efficient as well as decorative. Regardless of the style you choose, you'll find these fireplaces in a variety of looks, sizes, heat-output levels, and prices. Plan to connect a direct-vent gas fireplace to existing gas lines; LP-fired models are also available. These units offer a combination of aesthetics, efficiency, safety, and ease of installation. They're vented to the outdoors with a short length of two-in-one pipe that carries out combustion byproducts and draws in fresh air for combustion. The pipe can make two right-angle turns without losing efficiency. You can choose a fireplace that's freestanding or ready for framing; its function may be decorative or to provide heat. A major advantage of having a gas fireplace in your home is that if your power fails, it can provide some heat (and some provide quite a lot—check the BTU output ratings of the units you're considering).
Ventless Gas Fireplaces (also called vent-free)
Gas fireplaces exhaust combustion byproducts directly into the room. They're slightly more efficient than direct-vent units and are even easier to install, but they deplete the room's oxygen supply, produce fumes that can be a health hazard, and are more risky for basement spaces. Some states have banned their use. Most of today's ventless gas fireplaces are required to include an oxygen-depletion sensor (ODS), a safety feature that warns if oxygen levels in the room are becoming low. For health reasons, you're much better off with a direct-vent appliance.
If you plan to finish your basement floor with stone or tile, consider installing a radiant heating system first. These systems not only warm the floor, but increase the overall temperature of the room, often eliminating the need for additional heaters. You can install a radiant heating system yourself—they are available at most home centers—or you can hire a flooring professional to install the system for you.
For rooms where you plan to use other finish flooring materials, such as carpeting, consider installing a wood subfloor with sleepers (floor joists that rest directly on the concrete slab). Use sleepers to protect a floor from condensation or as an alternative to a liquid leveler if you don't want to fix cracks, tilts, or imperfections. You can also install sleepers if you want to insulate the floor. You must install a wood subfloor if your finished floor has to be nailed down.