Average age of homes in the USA is 37 years old. Lots of homes in Steamboat Springs are built in the 70s and 80s with some of them being a century old. High cost of these homes often prohibits demolition and a new home construction, with extensive remodeling being the most economical option. Remodelings are more challenging than new construction as there are too many unknowns before the project is started. Our climate conditions in North West Colorado, despite long winters, are favorable towards longevity of the structures. Dry winter, followed by couple wet months, another dry summer and couple wet months in the fall with an annual average rainfall of 20”, promotes drying and longevity of the structures. Mountain Contracting is following Building Science principles in it’s remodels in order to ensure continual longevity of the structures, water vapor control while reducing energy needed for heating and cooling. In order to provide measurable results ACH50 blower door test and thermal imaging is performed before and after to quantify improvements in air infiltration control and identify troublesome areas. Increase in thermal performance of the house, while appearing as a pretty straight forward approach, can have severe negative effects on the structure if all details are not considered properly.