frequently the question comes up on what makes more financial and practical sense? Is it better to build out with a room addition, or build up with a second floor addition?
The short answer is, if you have the land it is probably better to build out than to build up.
Building any home addition is a major undertaking. However, building a second story addition has significant more risk and interruptions associated with it.
First, local codes need to be checked to see if adding a second story addition is even feasible.
Second, the existing foundation needs to be inspected by the local building inspector, architect, or foundation contractor to see if the foundation can support a second floor. Concrete footings and foundation requirements usually vary on the type of home being built. A second story home creates significantly more load on the concrete footings and foundation walls. Consequently the footings and foundation walls are typically built more ruggedly for two story homes.
Third, the roof has to be torn off the home. This leaves the home vulnerable to the weather such as rain, snow and wind. Also, removing a roof in a controlled manner also takes significant time and labor which adds to the cost of the project.
Forth, frequently the homeowners need to find temporary housing elsewhere, as it is nearly impossible to live in the home while the roof is removed and replaced with another level.
Fifth, although every attempt is made to maintain the integrity of the first floor of the home, inherently there are risks of damage to the first floor ceilings and walls. Ceilings frequently are cracked while the second floor is being constructed.
Building a second floor addition is not an impossible endeavor. However, it does require more up front work and presents more risk to the existing home structure while being constructed. If you have limited land, then it may be your only alternative to create more space in your home. Again, however, if you do have the land it is probably a better bet to build out with a room addition.
Articla , Atlas Green Homes