Category — Insulation

I am getting a lot of calls from friends who know I am a builder asking about the water leaking through their ceilings and walls.  With all the snow in the Washington Metropolitan area over the past weeks, homeowners might be seeing problems that they have never encountered.  What is occurring is a phenomenon called an ice dam.   As the snow goes through a melt and freeze cycle, the ice that is formed creates a dam and pushes the water back into the home.

Interestingly ice dams are caused by too much heat in the attic.  The heat causes the snow on the roof to melt, which freezes up again when the water travels beyond the heated attic space.  The water freezes at night in colder temperatures and melts again during the day.  When the ice and snow melts there is simply no where for the water to go except back into the home.

There are two conclusions I can make about ice dams that are within your control.  (1) make sure your attic ceiling is properly insulated.  If you have an older home, call an insulation company or Natelli Homes and evaluate adding more insulation in the attic to keep the heat in the living spaces, not in the attic. (2) make sure your attic is properly ventilated.  Air needs to travel from outside through the attic and then through a gable or ridge vent.  The attic temperatures need to be cold if not the same as the outside temperatures. Most homes have a perforated vent in the cornice – you know, the ones that are filled solid with paint.  Those need to be perforated to allow lots of air to flow in and out of the attic.  So if yours are painted shut and have no visible perforations, call Natelli Homes or a siding contractor to replace or correct those vents.

Ice dams are not always preventable but a well constructed home, such as a Natelli built home, would normally not be subject to this issue.  Click on the following link to State Farm Insurance which gives a couple of good sketches, explanations and things to might do to prevent ice dams.  http://www.statefarm.com/learning/loss_prevent/learning_lossprevention_icedams.asp

As always, feel free to contact me at bob@natellihomes.com or visit our website at www.natellihomes.com

It must be hard for a consumer to decide how to select replacement windows or windows for a new home.  How do you start, where do you start and who do you trust for such an important investment?  All the manufacturers claim high efficiency glass, tax incentives and new and improved technologies.  In my career at Natelli Homes, which is going on 25 years in residential construction, the window and door industry has grown and improved the most.  The standards for all the major manufacturers are so much improved that I would venture to state that there are arguable financial and performance benefits to replacing windows that are only 10 years old.

Windows and exterior doors are the biggest contributors to heat and energy loss in a home.  People notice it more in the winter when we can feel the cold spots and drafts around windows and doors, but imagine how much is also lost in the summer when we are not quite as sensitive.  Poor performing windows and exterior doors contribute to an immeasurable amount of energy loss in our world.

Again, where does one start?  You might start with the U-value of a window which is a measurement of 4 combined ways windows lose heat.  This is a standard by which a homeowner can evaluate the performance of manufacturers on an even playing field.  Simply put, the U-value of a window combines the heat loss of a window through (1) radiation, (2) convection, (3) air leakage and (4) conduction.  The lower the U-value the better performing the window is.

I found a great sketch in an article by Paul Fisette in Fine Homebuilding.  Paul Fisette is director of the Building Materials Technology and Management Program at the University of Massachusetts in Amherst, MA (www.umass.edu/bmatwt). Chart information courtesy of W. W. Norton & Co. Inc., except where noted. Photo: Brian Vanden Brink; drawings: Dan Thornton.