Infrared Training Center

Wednesday, July 30, 2014

Just Scrape and Paint…or Not!

ITC instructor Ron Lucier is back with another great post, one that I can certainly relate to having recently moved from an old house that once had similar moisture issues.  Yes, they can be fun to renovate, but older homes are not for everyone, especially when a lot a scraping and painting (or worse) is involved.  Here’s Ron’s take on something that he recently dealt with at his house which also includes a couple of infrared images and some thermal science that our building thermographers should enjoy:


Renovating older homes can be fun. Or not. One thing for sure is they are full of surprises and expensive!

I own a horse farm and the house was built in 1910. Not sure when the porch was added but I noticed the other day that it is the only section of the house that doesn’t have rain gutters (ugh!). I also noticed that one section has paint that was peeling while the other areas of the fascia did not.

An inspection with my T650sc was in order. Yes, I am hung up on the grey scale and in the first image I used a blue interval isotherm. I have water damage:

just-scrape-02

Looking under the soffit…

I confirmed that the water has spread and I probably have to replace that as well:

just-scrape-03

Why does water appear darker to the IR camera? Because of latent heat. As water evaporates there is a drop in temperature. Latent heat is the amount of heat necessary to cause a change in phase – here from water to water vapor. Since there is a loss of heat, there is a drop in temperature. Simple science but a very important use for your IR camera!

This is a simple repair for this homeowner and yes I will be adding gutters. I’ve inspected the remainder of the house for moisture but fortunately haven’t found anything else. I do have two barns, though…

- Ron Lucier, ASNT NDT Level III