Last week I reported that adding an attic bedroom returned a higher value than almost any other remodeling investment. I suspect that other functions in the attic are also sound investments such as an attic home office or playroom. While some of my clients think about putting a home gym in the attic, I usually advice against it simply because heat rises and, for me, it would be too warm in an attic to exercise.
Here are some things to think about if you want to expand your living space into the attic.
1. Structure: Most older homes – like the ones I work on – have an open “A-Frame” structure in the attic. If the height is sufficient (see below), this I the right structure to start with. If, instead, you see a network of W-shape trusses supporting your roof, don’t think about using this space – it would be cost prohibitive to open up this structure for living. You may also need to reinforce the floor joists to support living space in the attic. A contractor or engineer can help you figure out whether the floor joists require reinforcement.
2. Staircase: You’re going to need to comfortably and safely get up and down from your new living space. Most existing staircases into an attic won’t meet today’s code. The tread depth needs to be at least 10”; the rise needs to be less than 7-3/4”; the width of the staircase needs to be at least 36”. Enlarging an existing stairway or adding a new one will affect spaces below. A straight-run stair will consume 10 to 14 feet of floor space; a stair designed with an intermediate landing and two runs needs about 8 feet on the lower level. (This is based on the International Residential Code; check your local building codes to see if your jurisdiction requires something different.)
3. Ceiling Height: For a habitable attic room with sloped ceilings at least 50% of the ceiling must be at 84” or higher (This is based on the International Residential Code; check your local building codes to see if your jurisdiction requires something different.) Remember to calculate the thickness of the finish materials when you calculate headroom. Notice how these different attic bedrooms use different strategies for handling the ceiling – from open collar ties to closed ceilings.
4. Use windows, roof windows & skylights to achieve daylight and natural ventilation. I find the slanted roof windows almost irresistible in an attic bedroom. They provide a sense of coziness that can’t be replicated anywhere else. The Washington DC area has hot summers so I avoid skylights on the southern and western roof exposures because they just bring in too much sun and heat. On a northern and eastern roof exposures, they bring in soft, wonderful cool light. A bedroom also needs a means of egress in case of fire or other emergency. So work with your contractor or skylight supplier to make sure that whatever you install meets code for your area.
Also consider borrowing light from adjacent areas. We used French doors on this attic office space to borrow light from the large windows in the stairwell.
5. Consider Adding One or More Dormers — these small additions that raise the roof over a portion of the attic will boost usable space and create the feeling of living in the treetops.
6. Attic Bath – To keep costs in check, you’ll want to locate the toilet directly above a toilet on lower levels. This will also put you above water supply lines. You’ll have to work with your plumber to discuss how to get hot and cold water up and waste down without too much disruption on lower floors.
7. Heating and Cooling Your Attic Bedroom. Remember that hot air rises. This can make attics particularly hot in the summer (and delightfully warm in the winter). For those of us who like to sleep in particularly cold room, an attic bedroom can pose challenges. I sleep in an attic bedroom and put in a multi-zone furnace/air conditioning system that allows me to set the temperature as low as I want. But since hot air rises, the only way I can keep the attic bedroom cool in the summer is to also have a physical barrier (a weather stripped door) that keeps the hot air from rising in my bedroom. Consult a heating and air-conditioning contractor to evaluate the cost adjusting your system to accommodate living space in the attic.
8. Be creative about storage. The space under the eaves that are too low to walk under are perfect places for built-in storage.