A Garage Wall Is Still An Exterior Wall

By
Home Inspector with Jay Markanich Real Estate Inspections, LLC 3380-000723

A garage wall is still an exterior wall.

And, as such, if it abuts the house, it needs to be insulated!  Remember the 5% Rule!

On a new construction inspection I noticed something interesting.  The room adjoining the kitchen and garage was very warm.

The area in this photo is in the garage attic space.  It is above the garage ceiling, but still abuts the house.

It opens to the entry from the garage, which is also a combination mud room and laundry room.

Entering that space from the kitchen I noticed it was kind of warm.

It had its own floor register and was serviced with HVAC, but that wasn't working.

So the question is why would that space be warmer?

That is what prompted the view in the garage attic space.

The thermal image here clearly shows what happens when the wall from the garage to the house is not insulated.

But there is a second culprit.

A small attic space above the laundry room also has its own entrance, which is similarly experiencing heat.

What we have is a large area at the edge of a room that is poorly insulated.

That brings us to the 5% rule.  Many insulation studies have shown that if 5% of a given space - a wall, a ceiling, or floor - is poorly insulated, or is missing insulation, that 5% will bring down the R-value of that space as much as 50%.

I have written a blog on this study which can be read here.

Looking at the wall and ceiling near the door to the garage it is evident that insulation is missing, or poorly applied, in the walls and ceiling.  The attic access hatch also needs to be insulated.  In my opinion the best way to insulate that is Styrofoam.  A later of 3" of Styrofoam provides about R-15 and weighs nothing.  Glued to the drywall of the access hatch it is a permanent insulator.

My recommendation:  if rooms feel warm or cool there is a reason.  The reason is insulation!  Certainly the naked eye can inspect the insulation to see how well it is applied, but if access is difficult and that is not possible the absolute best way is with a thermal camera!  And the 5% Rule  always applies.  It doesn't take much poorly-installed insulation to affect the comfort of a room!

 

 

Posted by

Jay Markanich Real Estate Inspections, LLC  

Based in Bristow, serving all of Northern Virginia.

Office (703) 330-6388   Cell (703) 585-7560

www.jaymarinspect.com


close

This entry hasn't been re-blogged:

Re-Blogged By Re-Blogged At
Topic:
ActiveRain Community
Location:
Virginia Prince William County Bristow
Groups:
Dedicated Bloggers
Professional Home Inspectors
Addicted to Active Rain
WeBlog Anything (almost)!
Best Practices
Tags:
insulation
insulation missing
insulation rvalue
insulation poorly placed
five percent rule of missing insulation

Spam prevention
Show All Comments
Rainmaker
3,574,980
Sheila Anderson
Referral Group Incorporated - East Brunswick, NJ
The Real Estate Whisperer Who Listens 732-715-1133

Good one Jay. Garage walls are all exterior for me as mine is detached.

Jun 22, 2016 09:55 PM #1
Rainmaker
1,843,215
Jay Markanich
Jay Markanich Real Estate Inspections, LLC - Bristow, VA
Home Inspector - servicing all Northern Virginia

Then they are likely not influencing the house Sheila!  Hence, no insulation!

Jun 22, 2016 10:04 PM #2
Rainmaker
3,237,087
Sally K. & David L. Hanson
EXP Realty 414-525-0563 - Brookfield, WI
WI Realtors - Luxury - Divorce

Ahhh...when you are hot you're hot...and not you are not..your thermal camera has certainly a wealth of stories to tell homeowners !

Jun 22, 2016 10:07 PM #3
Rainmaker
3,238,715
Wayne Martin
Wayne M Martin - Chicago, IL
Real Estate Broker - Retired

Good morning Jay. Such a simple cure, why not just do it? Enjoy your day1 

Jun 22, 2016 10:42 PM #4
Rainmaker
1,843,215
Jay Markanich
Jay Markanich Real Estate Inspections, LLC - Bristow, VA
Home Inspector - servicing all Northern Virginia

And, S&D, in the winter, when you are cold, you're cold!

It is simple Wayne, and even more simple to do it before the drywall!

Jun 22, 2016 11:29 PM #5
Rainmaker
565,450
Fred Hernden, CMI
Superior Home Inspections - Greater Albuquerque Area - Albuquerque, NM
Albuquerque area Master Inspector

That's the first thing I noticed when I started using a thermal camera, I was missing this kind of stuff till now!

Jun 23, 2016 12:07 AM #6
Rainmaker
1,843,215
Jay Markanich
Jay Markanich Real Estate Inspections, LLC - Bristow, VA
Home Inspector - servicing all Northern Virginia

One of the first things I learned was how much insulation can slip down walls, Fred.  Sometimes 1/3 of the wall is without insulation!  Without a camera, who would know?

Jun 23, 2016 12:26 AM #7
Rainer
300,956
Stephen Weakley
Nationwide Mortgage Services - Rockville, MD

Very interesting rule.  As little as 5% can cause a 50% loss in R-value.  I put off redoing my attic insulation again this spring, and I am sure my electric bill will reflect my inaction!  I promise, this fall.........

Jun 23, 2016 07:00 AM #8
Rainmaker
1,843,215
Jay Markanich
Jay Markanich Real Estate Inspections, LLC - Bristow, VA
Home Inspector - servicing all Northern Virginia

You can call me anytime about that Stephen.  I recommend blown-in cellulose on top of what you have.  It has a 3.7 R-value per inch, and only weighs 1/3 pound per square yard of R-15 depth.  Since it is recycled material it is pretty cheap.

Jun 23, 2016 07:15 AM #9
Ambassador
3,839,187
Kathy Streib
Room Service Home Staging - Delray Beach, FL
Home Stager - Palm Beach County,FL -561-914-6224

Jay- I should have had you look at our house when we were living in River Creek.  It was an attached garage with the master over it.  The bedroom was never that cold but my desk area near the utility room and garage was cold enough to hang meat.

Jun 25, 2016 04:00 AM #10
Rainmaker
1,843,215
Jay Markanich
Jay Markanich Real Estate Inspections, LLC - Bristow, VA
Home Inspector - servicing all Northern Virginia

Insulation is always the culprit in that circumstance, Kathy.  I have done other River Creek houses and they are spotty.  Plus, in tall walls, the insulation has sunken down the wall.

Jun 25, 2016 04:35 AM #11
Show All Comments

What's the reason you're reporting this blog entry?

Are you sure you want to report this blog entry as spam?

Rainmaker
1,843,215

Jay Markanich

Home Inspector - servicing all Northern Virginia
You may contact me anytime...
*
*
*
*
Spam prevention

Additional Information