Living Down Under…Adding Living Space
Turn a Basement into Living Space
There are several ways to make a small house larger (short of moving) – you can build out, up, or down. Building out with an ell addition isn’t always possible, practical, or affordable. Going up (which we covered in our last article Growing Up…Adding Living Space) is a great solution in many cases, but can require some serious changes to the roof line, not to mention stairs.
That leaves going down by finishing the basement. This will often be the least expensive option. There’s always room on the lot, there’s no need to put in more foundation, there are already stairs to the basement, and the roof line can stay just as it is. Before you start putting up walls and throwing down rugs, however, you need to consider the possible downsides to going downstairs.
Darkness
The furnace doesn’t need natural light, but people do. Every bedroom should have a window – two if possible. A TV room doesn’t need as much natural light, but a game room does. Consider using doors with windows in them so light will get into the interior spaces. Patterned glass or blinds can provide privacy when needed. Consider removing the cellar door and using half walls around the stairway so light can flow down from above. Put in plenty of light fixtures, including wall sconces. And use light paints and brightly colored fabrics and fittings to make the space seem lighter.
Dampness
You should assume it’s there and will turn into mold if you let it. Plan on doing everything you can to seal the perimeter walls and floor. Fill cracks, paint the surface with a sealant, and cover walls and floor with a vapor barrier before putting on insulation and finished surfaces. Use wall and floor finishes that are designed to handle dampness. Make sure the window wells will drain properly. Explore the need for curtain drains or gutters with diverters to shed rainwater well away from the house. If you have a sump pump, improve the outflow and install a battery backup in case the power goes out during a heavy rainstorm.
Ventilation
An energy efficient heat exchanging ventilation system will keep down the damp, provide fresh air to what could be a stuffy space, and also prevent any build-up of carbon monoxide from the furnace or hot-water heater. Put in a carbon monoxide alarm. Also test the cellar for radon, which can come from the granite gravel used in concrete. If you find radon, definitely ventilate, but also adjust your wall finishing methods to make sure the radon is completely sealed out.
Access
The stairway is there, but it may need to be brought up to code (proper stair height and depth etc. – see our article on stairs [link]. You may want to put in a landing or make some other change to its configuration, in order to make the best use of the downstairs space. And consider if the windows are large enough to be used as fire escapes. Is there a bulkhead entrance? It will need to be well sealed against drafts and water, but could provide a second way in and out. Is there enough slope to your property to put in a full-height outside door to the basement?
Warmth
A cool basement can be a wonderful place in the summer, but the other seasons will call for more warmth. Insulate the perimeter walls with rigid foam (over that vapor barrier). If you have enough headroom, consider a layer of foam on the floor as well. Put the heating sources down low, at baseboard level. Consider wall-to-wall carpeting (synthetics, because of the potential damp), along with throw rugs. Provide good curtains to pull over the windows during the night.
Headroom
You may need to level out sagging joists and move heating ducts or plumbing in order to fit in a finished ceiling. A suspended ceiling will provide access to all those mechanical systems and provide room for recessed lighting. (But don’t bury all of the lights in the ceiling – that can make the space seem darker than it really is.)
Noise from Above
Insulate between the joists and use sound-deadening ceiling materials. Also consider adding carpeting and rugs on the ground floor, particularly over the downstairs bedrooms.
Mechanical Systems: Heating, Plumbing, Wiring
When you put in the walls, leave plenty of room around the furnace, hot water heater, and electrical panel so that they can be serviced and replaced if necessary. It’s also a good idea to insulate all pipes and ducts before you cover them with finished walls and ceiling. This will reduce noise and condensation.
Space
Don’t try to squeeze in too many rooms. The people living downstairs shouldn’t feel like they’ve been buried! And consider using built-in units to make the most of the wall space while leaving plenty of room to move.
With all the above in mind, don’t get discouraged. These problems have all been solved before. You’ll find plenty of detailed advice online, along with links to damp-resistant products, and you’ll also find that building supply people and experienced contractors know how to help you avoid any real problems. That means you can focus on the fun stuff – floor plans, fixtures, furniture, and colors.
