Yes, it does matter how the house is situated, particularly with regard to forms -- mountains and water.
The direction from which the qi (chi) flows changes every 20 years; usually, the 20-year period in which a house is built is good; there are always exceptions. Building a home gives one the opportunity to maximize the qi and to use the energies most effectively.
In an existing structure, there should be some type of 'mountain' (building or hill) on either side of the building and at the back; these protect the qi for the home. There should be no hill at the front; the road is considered to be a river (water). Real water is even better. Imagine yourself sitting in an armchair where you have support on three sides; this is similar to the protection that your home needs.
The good energy is coming from the Northeast in this period; there must be NO real water (i.e., ponds, pools) in this area of the yard. The Wealth direction is from the Southwest, so if you have a window or door there, be sure that it is opened a lot and it will bring good qi to you -- this helps both the Wealth and Health aspects of the home.