Betterment is a home improvement project that adds value to real estate. Betterments are usually contrasted with routine maintenance. Maintenance costs do not add value to a home because the repairs are required for a home to maintain its current value. Constructing an addition on your home is one type of betterment. Building a new deck is another kind of betterment. Say that you have a home that is your ideal property. It has three bedrooms and two bathrooms, but there is no patio or outdoor room. You originally paid $100,000 for the home, and decide to build a deck that costs $5,000. Your deck is a betterment project because it adds value to your home. Now, the book value of your home is $105,000. This is the original purchase price plus the amount of the betterment that you undertook.