These days misinformation is rampant and online marketing efforts will often sight bad information in an attempt to provide helpful content. Lately I have been seeing too many “helpful links” shared with good intention containing awful home maintenance tips. So I have decided to do something about it. 

Bad Tip #1 “If you see a gap outside your windows or doors caulk it”

So this beauty is the bad Home Maintenance Tip that caused enough indigestion to inspire this list. This awful advice is recklessly vague and has been broadcast to homeowners for far too long. Right about now you’re thinking; “caulking around your windows & doors is good right?”.  That’s partly true. Caulking in the right places around your windows & doors is good but caulk in the wrong place can and will cause real problems.

So let’s dig into it.

In most circumstances a window or door will have been provided with a head flashing above. This flashing, also called a cap flashing is in place mainly for 2 reasons:

1. to keep water out and
2. to let water out.

A head flashing above a window or door is integrated with your Weather Resistant Burrier(WRB) and provided with a 1/8″-1/4″ gap. And for good reason because water from humidity in the air will condense on a WRB. Then gravity will cause this water to drip down like beads of sweat on your uncle Larry’s forehead in the back seat of that 1986 station wagon, with no AC during that summer road trip. You know the one I’m talking about. Building Science Nerds (as I like to call them) long ago figured out that if you don’t allow this water out it will cause damage. Damage like wood rot or mold. The gap above that flashing is like cracking a window in the backseat of that station wagon to let your uncle Larry’s shirt dry out. And this isn’t a new idea. Wood molding profiles that are sloped and integrated with the felt paper behind the siding are commonplace above windows and doors on historic homes.

“I highly advocate DIY, just seek out good advice first.”

Following this bad home maintenance tip, well intentioned DIYer’s armed with caulk guns set out on a mission to find and fill gaps. Unfortunately without the right knowledge they often do more harm than good. Caulking is one of the final steps of exterior detailing. Failures in exterior detailing account for the vast majority of water intrusion issues. While the act of caulking may be simple, to do it well you need knowledge of basic building science principles. And knowledge of installation standards for the materials specific to your home. In many cases this is a task best done by professionals or under professional instruction/supervision. Just to be clear I highly advocate DIY, just seek out good home maintenance advice first.

Manufacturer’s installation guidelines for exterior products are littered with details showing where gaps must be left to allow for water to weep out of the wall system. And not just at the head flashing for windows and doors either. This is just one example of the numerous gaps and holes that have been designed into the wall system. These gaps and holes keep your home dry and rot free. I’ve included a few examples here, I will go in depth about these in a future addition.

The cost of following bad advice

Sending an unwitting homeowner on a gap hunt with a caulk gun can be disastrous. Removal of the resulting misplaced caulk is a bigger job than applying it! And doing so will almost certainly cause damage to surfaces. Or worse, the caulk remains in place and allows for concealed wood rot at the framing. Now your wife’s all like “Bob I told you to hire a professional!” and you’re all like “But Home Ad-viser said I should fill the gaps!” Good luck acting cordial at the dinner party tonight. The building Science Nerds are like “maybe we should reschedule Bob”  But your wife’s like “No no no tonight’s PERFECT“… Then she gives you that look..  Super awkward.

Don’t spread this terrible home maintenance tip. While caulking maintenance is important, caulk in the wrong place is damaging. Consider what you share and who it’s coming from. If someone is writing articles on home maintenance and not qualified on the subject you should be skeptical. It is unlikely they have studied the resources necessary to produce accurate & helpful advice. It’s kind of like taking cooking advice from your dog, sure they love to eat food, but an expert on cooking they are not.

 Below are links to the source documents for the images in this article.

Manufactured Stone Installation Guide  –   Vinyl Siding Institute Installation Guide   –   Hardie Plank Siding Installation Guide

Have You Ever Followed bad Advice During a DIY Project? Let me know in the comments.

I hope you enjoyed reading this as much as I did writing it. Look out for the next addition where we will tackle more awful home maintenance tips in the most entertaining way I can muster.

Arthur Duhaime is a Ohio Licensed Home Inspector and his industry leading home inspections glean insight from 2 decades of real construction industry experience.