Cause & Effect, Home Improvments may cause damage

I recently went to a home and garden show and was surprised at how many products were being sold as a cure all. Claims of reducing energy costs, never paint again and more were heard over and over. I asked a few of the people at the show about the drawbacks of their products and they all said the same thing, “There are none”.

Well I have news for you, buildings are more than a bunch of different components thrown together and everything you do has an effect on something else. If you are running the clothes dryer while the air conditioning is on you are paying to cool the air in the home, then the dryer takes the cool air and you pay to heat it and blow it outside, then the home is under negative pressure so it draws hot air from outside through vents, doors, & windows. Then you pay to filter and cool that air so the dryer can heat it and so on and so on.

I am going to talk about two of the products I saw at the home show although I could likely write a different post every day for a month if I choose to do so.

Radiant Barrier in the attic:
Radiant barriers are typically installed in the attic either on top of the insulation or under the rafters (top chord of the trusses) and reflect the radiant heat back up thereby preventing it from entering the interior of the home. It is a great idea and works as long as it is vented. There are roofing companies that are installing this barrier under the shingles and what they don’t tell you is this cooks the shingles from underneath and many of the shingle manufactures will void the warranty if the shingles are installed directly on a radiant barrier. So while the roofer may install it that way, a few years from now then the roofer is out of business, the manufacture won’t warranty the roof.

That could be a problem.

The second item is sold several ways, liquid vinyl paint, elastomeric paint, ceramic paint, etc.
All of these paint like products claim to waterproof the exterior of the home, some claim it is the last paint you will ever need to apply.
The truth is these products do create a moisture barrier on the exterior of the home, however every opening i.e. window, door, outlet, hose bib, light, vent etc. needs to be sealed on a regular basis or moisture will enter at the joint between the opening and the paint like product then since the moisture barrier is on the outside of the home the moisture gets trapped on the inside.

Moisture blister under elastomeric paint

Then there is the issue of the moisture from inside the home, if you cook, clean, bathe or breathe you have moisture inside your home, most construction has a moisture barrier in the wall but not a vapor barrier, this means that the moisture can migrate out through the walls, it means your house can breathe. Have you ever had a pair of plastic shoes that didn’t breathe? How did they smell after moisture built up inside them? No imagine your home not being able to breathe, not being able to vent the moisture from the inside to the outside.

Before you make any improvements to your home consult with someone that knows and understands basic building science. Not the person trying to sell you their product, someone that nothing to gain if you decide to bake the changes or not. It could be a home inspector, a general contractor or someone that specializes in building science or environmental issues.

If you want more information about Arizona home inspections, what to look for in an home inspector, common issues found during a home inspection or how to get your home ready for a home inspection click the links.

Scott Warga, is the Qualifying party for ACSI American Construction Specialists and Investigations LLC,(ROC216772) a dual licensed residential and small commercial contractor. He is also a qualified Phoenix home inspector certified by the Arizona Board of Technical Registration (#38062) and was appointed to the Arizona Board of Technical Registration’s Enforcement Advisory Committee. He has years of construction experience and has performed residential and commercial property inspections for over 10 years. He has specialized in forensic inspections, investigating failed, damaged and defective construction for over 5
years. He is a member of the American Society of Home Inspectors (ASHI), (#205826) and currently sits on their board of directors. He has been an instructor of home inspection at Mesa Community College, for Inspection Training Associates, a Kaplan Professional School and Arizona Sun-Tech Home Inspection School. He has served as District Chairman & Vice President for the Arizona chapter of the American Society of Home Inspectors and an approved instructor for both them and the Arizona Department of Real Estate. If you need an Arizona Home Inspector, he is your guy.

Be Sociable, Share!


  1. Great post Scott, too often energy saving products are recommended with no real understanding of how it effects the home. For example, in some cases solar attic fans have been shown to suck conditioned air from the house up to the attic which creates health and safety hazards as well as decreasing efficiency. Look forward to future posts.

Speak Your Mind

Site Designed by Go Pro Local