There are two kinds of home-improvement projects.

There are projects you plan.

And then there are projects your wife starts digging while you’re still explaining why the project is a bad idea.

This was the second kind.

It began with a deck.

Not an unusual deck. A nice deck, actually. Composite decking, black railing, landscaping around it. The sort of project where you finally stand back, admire several weekends’ worth of labor, and begin mentally returning your tools to their rightful places.

My wife, Karen, looked at it differently.

She looked underneath it.

“I don’t want critters living under there.”

I knew immediately where this conversation was headed, and being a man with decades of experience in several trades, I was prepared to provide the necessary technical expertise.

“You can’t really keep critters out from under a deck.”

There.

Problem solved.

Except Karen had not asked whether critters could be kept out. She had announced that she did not want them there.

This distinction would become important.

I explained the obvious engineering problem. You couldn’t easily put lattice around it. You couldn’t put boards around it. You couldn’t put siding around it (her idea). It wouldn’t matter. A raccoon, rabbit, squirrel, chipmunk, groundhog, or whatever other furry excavation contractor happened along could simply dig underneath.

Karen considered this.

Then she said something along the lines of:

“Why don’t we dig a trench around it and pour concrete in the trench?”

This was clearly getting worse.

The Squirrel Foundation

Her proposal was wonderfully excessive.

We would dig an 8″ deep trench around the perimeter of the deck.

We would stand wood–cedar siding down into the trench.

We would pour approximately a dozen bags of concrete around the bottom of the cedar.

The cedar would continue upward behind the composite skirt board around the deck.

Thus, an animal attempting to get underneath the deck would encounter cedar.

If it attempted to dig underneath the cedar, it would encounter concrete.

Karen had, essentially, proposed building a foundation for squirrels.

I hated it.

I explained that this was ridiculous.

I explained that animals dig.

I explained that cedar was water resistant but that burying wood in concrete and dirt was not exactly the detail you’d expect to find highlighted in an architectural textbook.

Karen listened carefully to my professional assessment.

Then she got a shovel.

This is where an important biographical detail belongs.

Karen’s father was the man who taught me practically everything I know about the trades.

Carpentry, electrical, plumbing, construction, repair, fabrication. He was the kind of guy whose lessons stick with you because they weren’t really lessons about how to use a particular tool. They were lessons about how to think about a physical problem.

And apparently, while I was receiving the formal education, Karen had been taking the same class from the other side of the dinner table.

This became particularly evident whenever I attempted to declare some nearly completed detail “good enough.”

Karen possessed a devastating five-word building code:

“Dad wouldn’t leave it like that.”

There is no effective response to this when Dad is the guy who taught you how to do it.

And apparently Dad wouldn’t leave an opening beneath a deck for squirrels, either.

I Went on Strike

I seem to remember refusing to help dig the first ten or fifteen feet of trench.

This was my principled stand.

I had evaluated the design.

I had rendered my professional opinion.

I was not participating in the construction of the Great Wall of Chipmunk.

Unfortunately, Karen possesses a personality characteristic that seriously diminishes the effectiveness of this negotiating strategy.

If I refuse to take the shovel, she takes the shovel.

So there she was, digging.

And the problem with watching somebody stubbornly dig a trench for an idea you have already declared stupid is that every additional foot raises the stakes.

At five feet, you can still win.

At ten feet, you become concerned.

At fifteen feet, you begin realizing that this woman may actually dig the entire damn thing without you.

Eventually, I joined the winning contractor.

And somewhere during construction, something unexpected happened.

The stupid idea became clever.

The Cedar Was the Trick

We had cedar siding.

Real cedar bevel siding, the same basic stuff used on the house.

A cedar bevel board is thick along one edge and tapers down toward the other. Normally you install these boards horizontally with one overlapping the next.

For our decidedly nonstandard application, we put the fat edge down.

And suddenly the material made enormous sense.

The bottom didn’t have to be cut perfectly because it disappeared into a trench that was about to be filled with concrete.

The top didn’t have to be cut perfectly because it disappeared behind the composite skirt board.

Think about what that eliminates.

Normally, finishing the bottom of a deck against uneven ground is an exercise in measuring, cutting, fitting, trimming, checking, swearing, removing, cutting another eighth of an inch, reinstalling, and discovering that the ground three feet away is two inches higher.

We didn’t have to do any of that.

We put the cedar into the trench.

Wherever the bottom landed, it landed.

Wherever the top landed behind the skirt board, it landed.

Then I screwed through the composite skirt board into the cedar.

Done.

No precision cut at the top because nobody would ever see it.

No precision cut at the bottom because nobody would ever see that either.

The visible composite skirt board established the one line that mattered.

Straight.

Clean.

Finished.

Everything behind it could be gloriously indifferent to aesthetics.

This is one of my favorite kinds of construction trick: don’t become more precise than the project requires. Design the detail so precision isn’t required in the first place.

Need More Height? Add Another Board.

Some parts of the deck sat farther above grade than others.

That sounds like another problem.

It wasn’t.

Where one cedar board wasn’t tall enough, I used two.

They were siding boards, after all. Overlapping is literally what they were born to do.

Put one above the other with an overlap, fasten them together, and suddenly you’ve got whatever height you need.

No custom panel.

No sheet goods.

No elaborate framing.

No special-order product with seventeen proprietary clips and a 46-page installation manual.

Just another piece of cedar.

That was particularly satisfying because the entire assembly tolerated variation.

The ground could rise and fall.

The trench could vary slightly.

One section could require one cedar course.

Another could require two.

None of it mattered because the composite skirt board established a continuous visual line around the deck.

From ten feet away, you don’t see any of the engineering.

You see a deck that looks finished all the way to the landscaping.

Then Came the Concrete

Once the cedar was positioned, the trench was filled with concrete.

And this was the part of Karen’s idea I had originally dismissed.

I’d said animals could dig underneath whatever we installed.

Karen hadn’t disputed that.

She had simply removed “underneath” from the available options.

That’s actually very good problem solving.

Instead of asking:

“What kind of deck skirting keeps animals out?”

she had effectively asked:

“How would an animal defeat deck skirting?”

Answer: dig beneath it.

Okay.

Then make beneath it undiggable.

That’s a completely different way of approaching the problem.

The cedar closed the vertical opening.

The concrete closed the subterranean opening.

The composite board concealed the top of the entire contraption.

And the landscaping concealed the bottom.

The result was something that looked considerably more sophisticated than the construction method had any right to look.

But You Buried Cedar in Concrete

Yes.

I know.

There is undoubtedly someone reading this who has been waiting several paragraphs to say it.

You shouldn’t bury wood in concrete.

And as a general construction detail, I agree.

Wood plus persistent moisture is a longevity problem. Even naturally decay-resistant cedar is still wood. The transition around grade, where materials repeatedly get wet and dry, is particularly unfriendly territory.

If I were designing the same system today from scratch, knowing what I know now, I might substitute a modern rot-proof material for the buried vertical component.

PVC or an appropriate composite product immediately comes to mind.

But there are a few things working in favor of our original contraption.

First, it is cedar.

Second, the thick edge is down.

Third, we coated the hell out of it with a very durable black exterior stain/coating.

Fourth, this isn’t structural. The cedar isn’t holding up the deck. If it eventually deteriorates, my deck isn’t coming down.

And fifth, the thing has already spent years outside getting rained on, snowed on, frozen, thawed, splashed with mud, surrounded by mulch, assaulted by Illinois humidity, and generally subjected to everything nature could think of.

I recently crawled down and looked at it.

It’s still there.

Pretty damn solid, too.

Apparently nobody informed the cedar that it was installed incorrectly.

The Funny Part Is What It Looks Like

This whole story came back to me because I recently showed photographs of the deck to someone without explaining any of this.

They looked at the horizontal composite board around the bottom and essentially said:

“That’s a nice deck skirt detail.”

Exactly.

They didn’t notice the anti-squirrel fortification.

They didn’t see the cedar disappearing toward the ground.

They didn’t know there was concrete underneath.

They saw a clean horizontal architectural detail tying the deck into the landscaping.

That may be my favorite thing about the entire project.

The engineering disappeared.

Good construction often does that.

When something is really awkward, the finished result doesn’t necessarily have to advertise how difficult the problem was.

In this case, the solution doesn’t look like pest control.

It looks like trim.

The Skirt Board Couldn’t Skirt the Issue

Which brings me back to the skirt board.

A normal skirt board could have done exactly what its name suggests.

It could have skirted the issue.

Put something attractive around the bottom of the deck, hide the framing, call it finished and go have a beer.

Except Karen’s objection wasn’t aesthetic.

She didn’t merely want to hide what was underneath the deck.

She wanted to prevent anything from moving in underneath the deck.

So the skirt board couldn’t merely skirt the issue.

It had to solve it.

And that led to one of those wonderfully backwards DIY projects where the apparently excessive idea turned out to make the finished construction easier.

The trench eliminated the need for a finished bottom cut.

The composite skirt eliminated the need for a finished top cut.

The cedar accommodated changing heights simply by overlapping another board.

The concrete stopped digging.

The stain protected the cedar.

And the composite board concealed the entire operation behind one clean horizontal line.

What initially sounded like:

“Let’s dig a trench and bury cedar siding in twelve bags of concrete because Karen doesn’t like squirrels”

eventually became:

“That’s actually a pretty damn elegant way to finish a deck to grade.”

I hate when she’s right.

There Is, Unfortunately, a Larger Lesson Here

I’ve spent a lot of my life building and fixing things.

One of the great advantages of knowing several trades is that when somebody proposes an idea, you can immediately imagine the seventeen reasons it won’t work.

This is extremely useful.

It’s also occasionally a handicap.

Experience teaches you where things fail.

But sometimes that means the experienced person starts solving the problem by eliminating possibilities, while somebody else starts with:

“Well, why couldn’t we?”

Karen wasn’t thinking about conventional deck-skirt construction.

She had a squirrel problem.

Or, more accurately, she had a future hypothetical squirrel problem, which is arguably worse because there wasn’t even a squirrel yet.

She identified the failure mode.

They’ll dig underneath.

Then she attacked the failure mode.

Put concrete underneath.

That’s it.

The guy who knew how to build things had a list of reasons the idea was silly.

The daughter of the guy who taught him how to build things grabbed a shovel.

And that’s probably not a coincidence.

Her father taught me practically every trade I know.

But apparently he taught Karen something, too.

Maybe the more important thing:

If the problem is still there, you’re not finished.

Years later, I look at that deck and no longer see the ridiculous squirrel bunker I reluctantly helped build.

I see a clean composite skirt, a nicely finished transition into the landscaping, and a construction detail simple enough that I’d seriously consider doing it again.

Maybe not with cedar.

Maybe with something completely rot-proof next time.

But the trench?

Absolutely.

The buried barrier?

Yep.

The composite board hiding the whole operation?

Definitely.

And if Karen tells me to start digging?

This time I’ll probably just get the shovel.

After all…

Dad wouldn’t leave it like that.