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

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


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.




Original blog post on ActiveRain: Link to Blog Post

Up Up And Away! …Scuttle Hatches…………….A Best Practice Technique

Attic hatch

Here the ‘best practice’ that I’ve come across in the last few years is placing the hatch in the door swing space of  a bedroom. 

This does several good things;

1 It gets it out of tight closets that are difficult to position ladders in.

2. It does not require the emptying of shelves to gain access to the hatch.

3. Opening the hatch does not cause loose insulation or other attic debris to rain down on the clothes in the closet.

4. Positioning in the swing area of the doorway ensures that there will never be any furniture in the way.

5. It can be sized adequately, usually 24″ by 30 “, as it is not limited to closet dimensions.

It is more visible but;

·      Newer designs are done without the big trim moldings drawing your eye to it,

·      And the best ones have magnetic strip weatherstripping edges that lock into place just like a fridge door

·      And all you can see is a trim minimal square outline on the ceiling.

·      Above the door is out of sight for anyone looking into the room.

·      If a hatch has popped you are going to see it, but in a closet it may not be noticed for years.



Original blog post on ActiveRain: Link to Blog Post