Chris' Corner: Importance of proper Roof Ventilation

Importance of proper Roof Ventilation

I learned a lot about the need for proper attic ventilation in housing this summer.  Jay Markanich, my Active Rain Friend, avid blogger, and knowledgeable home inspector from Bristow Virginia, shared this informative post on the subject of Roof Venting.  Please read on if you would like to know more about this subject.

If you are looking to buy and/or sell a home in Tottenham or Beeton, please call me, Chris Smith, @ 1.866.936.3500 for information and assistance in achieving your Real Estate Goals.

If you want to leave a comment for, or to contact Jay, please click on his link below:

For attics that are not intentionally built not to ventilate, attic venting is extremely important.  And if the house has what is called a soffit and ridge vent system, you really want to see the soffit vent, if you please.

It's simple.  There are holes under the gutters called soffit vents.

There's a slice cut out of the top of the roof, which is covered to allow the air out.  That is the ridge vent.

Together they are called a soffit and ridge vent system.


Air comes in, warms, rises and goes out through the highest point.  It never fails.  The soffit and ridge vent system even works in winter time.

This ventilation system also helps to allow moisture to escape, especially during winter.

It is a very important system.

It's important that the same amount of air that comes in can get out!

Arriving at this inspection I noticed that two houses had all the wood trim wrapped with aluminum - the house I was to inspect and the one next door.

All of the other houses had wood trim.

Looking up I noticed something odd.

The house I was inspecting had aluminum siding put over the soffit vents.

Why is that important?


If no air gets in, no air gets out.  Therefore, THERE IS NO VENTILATION!

What should the vent look like?

See the house next door?

The soffit vents were covered, properly covered, with plastic made for that application.

These plastic soffit covers are manufactured with small holes to allow for air to get in.

The venting holes are placed every 12".

Covering the soffits with regular aluminum siding is NOT providing vent holes to allow air to get in.

If no air gets in, no air gets out!

The attic air stagnates.

The attic air is influenced by warmth from the house during the winter.

The attic air is influenced by coolness from the house during the summer.

When a disparity of temperatures exists, the laws of biology and physics say, condensation develops.

When condensation develops conditions improve that encourage "microbial growth!"

But you already knew that was coming!  See also how rusty the nails are?  The shingles are only a couple of years old.

And all this because, as some point, some "professional" came into the neighborhood and sold this occupant on why the wood trim needs to be covered with aluminum so it would be


Proof once again that just because someone has knowledge of HOW to do something, without experience with WHAT to do, or understanding the BEST PRACTICES of what one is doing, unintended consequences result.


My recommendation:  when someone proposes that something be done to your house, check around.  Don't simply check on the contractor who proposes the work.  Check on what is proposed to be done!  Be sure that one thing will not cause another.  Because, after all, there are certain laws in biology and physics that must be obeyed.  If they are not, you will be issued a citation - from a home inspector!




Jay Markanich Real Estate Inspections, LLC

Based in Bristow, serving all of Northern Virginia

Chris Smith CSSBB
          Sales Representative

Interested in Buying or Selling Real Estate?

  ph: 1.866.936.3500

Chay Realty Inc.,

Comment balloon 0 commentsChris Smith • November 05 2011 04:42PM