Insulation type and depth are checked. Different types of insulation require different depths to get the rating recommended for our area. Fiberglass fill here should average between 12-14" of insulation as a minimum for our area. Cellulose often is a 10-12" thickness. Again these are for the minimum thickness in attics. Low insulation can lead to higher energy bills and higher maintenance costs over the time you own the building.
As was mentioned above I am searching throughout the attic for any issues that can be seen. Improper wiring of fans and other electrical equipment could create a fire hazard. Improper venting of bathroom fan vents can create high humidity in the attic area. Low or missing insulation is important so I am checking the depth of the insulation in multiple areas to make sure it is the right depth. Leaking roofs, flues, and plumbing vent flashings are all searched out, ensuring that you get the most out of your home inspection. The roof structure is examined, searching for broken joists, trusses, cords, ridge boards, knee walls. Missing "H-clips" on sheathing and other structural issues are examined to ensure the roof structure is adequate for the home and not damaged.
The Image on the left shows where a chimney was leaking. All protrusions that go through the roof are examined in the attic. The attic will often be the best location to see where leaking is occurring because the cracks and leak points on the roof are not always large enough to identify with the naked eye.
In this instance a dark area at the rear perimeter of the roof sheathing indicates there was likely ice damming that occurred. Ice damming is a condition that takes specific instances to occur. For example: where in cold weather snow and other icy precipitation gathers on the roof. Naturally eventually some melt occurs, either from heat in the attic or from solar heating from the sun melting the precipitation. As the ice and snow melt the water runs towards the gutters. However here at the eaves before the gutters the water gets trapped and actually accumulates. Water that sits on the roof surface can saturate shingles and seep into the attic. Sometimes this water can saturate into the interior of the home. In this case it appears it only saturated the sheathing in the attic. A lack of insulation, clogged gutters and poor attic ventilation can all cause this condition to occur on homes that should otherwise not have this issue. Roofing contractors sometimes do not install the correct underlayment underneath the shingles or do not ensure it is properly installed without tearing before the shingles installed.
Home inspectors look for previous leakage, insulation being at the proper depth and for proper coverage of insulation. The issues identified in the attic inspection can save money, and save the home from the hazards of moisture intrusion.
Attics are an important area of a home inspection because of what they can tell you about the home. Attics are a key area where insulation and moisture intrusion can be issues. If not remedied these issues can create high cost issues in the home. A lack of insulation for example could be causing your heating and air conditioning system to be working more than necessary. This could lead to high cost of energy to run. It could also shorten the life span of the equipment making maintenance and replacement costs go up. Some insulation types limit air movement helping to reduce the drafty feeling inside the home, especially in the winter months.
Attics can help to show any failures in the roof surface. Failures in the roof surface can often be seen by means of staining of the joists, sheathing, insulation, flues, and vent pipes. When performing an attic inspection I am looking for evidence of this. One area I commonly find leakage is around the plumbing vents. The rubber boot flashing around them can fail and create a point of leakage inside the attic. Carefully checking the attic ensures there are no leak points. The attic will often show where leaking is occurring before such signs are readily evident in the home itself. It is also beneficial to find these areas before they stain drywall. These areas can also turn into mold and mildew issues if not addressed.
In this case during the home inspection there was a severed member of the roof truss. The way this home was constructed meant that if this was not corrected a failure in the roof surface under a load such as heavy snow or someone working on the roof could cause it to collapse in this area. The attic inspection makes the difference because identifying these issues can be almost impossible from out side the home, or even walking the roof surface.
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