Pop Goes The Hatch (Weasel) And So Does Your Energy Bill.

By
Home Inspector with Aspect Inspection

How many times do I see the following condition; a popped hatch.

hatch2

Yes it’s popped open or lifted when a door or window is opened somewhere and it’s a windy day or the wind is hitting that side of the house. The sudden increase in air pressure will lift the hatch (it’s not heavy).

It can even be pulled up as sudden gust of wind create a low pressure zone over the roof. This partial vacuum will pull higher pressure air form the house, lifting the hatch cover with it.

Most times it will just fall back down to the same place but sometimes it will catch due to misalignment and will stay open or partially open.

In a closet this may never be noticed till the next service call or inspection requires attic access.

 The heated (or cooled) air that can be lost through this is just phenomenal. Just visualize the plug being pulled on a sink full of water. That’s a house loosing hot air through the hatch. The air is not as dense as water but the same principles of fluid dynamics are at play. So it won't be as fast but it will be continuous as the 'tap' is always on (heating or AC system).

 For this reason I recommend hold down hardware unless you have the magnetic strip type.  (Hook and eye screws, barrel bolts, etc.).  The hardware also keeps the hatch tight against the weatherstripping to make it airtight.

 

 

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Comments (9)

Dale Ganfield
Leland, NC

Hi Robert, might as well be a chimney or open window if the hatch is askew or not seated properly.  A good recommendation.

Mar 14, 2011 01:05 AM
Robert Butler
Aspect Inspection - Montreal West Island, QC
Montreal Home Inspector | Aspect Inspection

You got it Dale.

Mar 14, 2011 02:25 AM
Adrian Willanger
206 909-7536 AdrianWillanger-broker.com - Seattle, WA
Profit from my two decades of experience

Robert~Great comment on an often missed item, what a energy suck, I've been on several blower door test and something like this would blow the socks off the test. Thanks for the post.

Mar 23, 2011 01:04 AM
Robert Butler
Aspect Inspection - Montreal West Island, QC
Montreal Home Inspector | Aspect Inspection

You're right Adrian, it is often missed and the fix is so inexpensive.

Mar 23, 2011 02:20 AM
Not a real person
San Diego, CA

You should come out here where they either leave it off because it’s too difficult to put back up or they seal it up so that it’s not ugly anymore.

Mar 23, 2011 05:06 AM
Robert Butler
Aspect Inspection - Montreal West Island, QC
Montreal Home Inspector | Aspect Inspection

Hi Russel, I've seen them with no insulation on them so they might as well be left off. I'd ask the owners if they're happy with their heating or AC costs.

Mar 23, 2011 05:14 AM
Susan Emo
Sotheby's International Realty Canada - Brokerage - Kingston, ON
Kingston and the 1000 Islands Area

I just advised my brother to do exactly what you suggested: inexpensive hook and eye screws!  Thanks for this.

Jul 06, 2011 02:57 PM
Robert Butler
Aspect Inspection - Montreal West Island, QC
Montreal Home Inspector | Aspect Inspection

Your welcome Susan.

Jul 06, 2011 03:26 PM
Anonymous
Kathy

Can u show a picture of what u mean

Apr 29, 2019 06:42 AM
#9