Every little bit helps. You can avoid adding to the impermeable surfaces of the world by remodeling within your existing building footprint rather than building new OR expanding beyond the current boundaries. Look around the house for space you already have. This is the low hanging fruit in any remodel by measures of speed, difficulty, return on investment, and baseline cost.
If you want to stay within your house’s existing footprint – basically the outline of your foundation – here’s where you look for space:
One: Finish the Basement
Most midwestern houses have a basement. It is a good idea to leave some portion of the basement unfinished. People prefer to keep some storage in basements and there are utilities usually found there which do better in a space larger than a closet – furnace, plumbing clean outs, utility sink etc. Those items can be quarantined into a utility room and set aside.
Typical basements have an equal amount of space to the floor above, so finishing the basement of a one story house can nearly double your finished square footage.
Consider the possibilities. You can create room for another bedroom, project room, guest suite, computer room, office, game room, kids play area, TV watching den etc. Adding plumbing for bathrooms or wet bars is sometimes less complex in basements than other areas of the house.
Two: Expand into the Attic
Depending on the pitch of the roof and the existence of stairs you might be able to add insulation, windows and finish materials to attic space and annex it to the house. If you already have a room or two under the roof, you can increase it by adding dormers to boost full height space.
Even under a low pitched roof you can use attic space as storage are in order to free up full height storage rooms elsewhere in the house and convert them to new living space. Or you can raise or change the roof line to make room to add a full floor or partial height additional space.
Attic space is fun, mysterious and cool. The distance from the rest of the house can make it an ideal location for a master suite, office space or teenagers room. It is great for any activity that needs a little more breathing room or separation from the rest of the family.
The house that my family moved into when my sister was in high school was purchased – in her opinion – purely for its attic bedroom, on which she called dibs sight unseen based on realtor photos.
Pay attention to attic related issues. You’ll need thorough insulation – both for the attic space itself and to keep the rest of the house cool. You may need to add more windows (both for light and ventilation). Maximize headroom and organize tight spaces so that there are clear areas for standing under the highest ceiling. Other activity areas like beds, desks, reading nooks and storage are tucked out of the traffic flow under eaves.
Three: Fill between House and Garage
This might include filling in an attached garage with living space, then adding on a new garage outside the building footprint. If the garage is not currently attached, you can think about filling in the space between with entry storage/ mudroom/laundry space.
If you have a two story house with a one story garage attached you may be able to expand the second floor area over the garage. (Note: this will require engineering approval).
Bonus: Convert Un-Conditioned Areas
Consider converting any open or three season porch areas to interior living space. Make sure that a project like this takes full account of thermal and moisture control. It isn’t as simple as replacing screens with window glass. If you are annexing the front porch for interior space make sure you are still accounting for a pleasant entry sequence into the house from the street.