Is the Dehumidifier Really Necessary or Is It Just an Upsell?

Jeff Robinson • August 25, 2026

When a homeowner finally makes the call, something shifts.


We come out and do a thorough inspection. We get under the home and look at everything — and we show you what we're seeing in real time so there are no surprises when we sit back down with you. You'll know exactly what's down there. You'll know exactly what it takes to fix it. And you'll have a clear picture of what your home looks like after the work is done.


No pressure. No scare tactics. Just an honest look at what's happening and a straightforward plan to address it.


Most homeowners tell us the same thing after that first visit.


They wish they hadn't waited as long as they did.

You Were Right to Ask That Question

Nobody wants to feel like they got played.


You call a crawlspace company, they come out, and somewhere in the conversation a dehumidifier gets added to the quote. It happens almost every time. And if you've dealt with contractors before — especially the big national ones — your guard goes up. You've seen how this works. One thing leads to another and the price keeps climbing.


So when you ask whether the dehumidifier is actually necessary, that's not you being difficult. That's you being smart.


Here's the thing though. This is the one time that instinct leads you to the wrong place.

Why the Skepticism Makes Sense

The crawlspace industry hasn't done itself any favors.


There are companies out there — big ones, with trucks in every city — that have turned the upsell into an art form. High pressure. Scary numbers. A long list of things you supposedly can't live without. After enough of that, homeowners learn to push back on everything. It's a reasonable response to an industry that earned the distrust.


So we get it. We really do. When someone questions the dehumidifier, we don't take it personally. We just want to make sure they understand what they're actually deciding — because this one matters more than most people realize.

Here's What the Liner Actually Does

When we encapsulate a crawlspace, we wrap it. The floor, the walls, everything. That liner seals the space off from the ground and the outside air.


That's the whole point of it. And it works.


But here's what most people don't think about. Once you seal a space, whatever gets in — stays in. Humidity doesn't just disappear. It has nowhere to go. It sits in that sealed space and builds up over time.


Mold doesn't need much to get started. A little moisture and something to grow on is really all it takes. A sealed crawlspace without a dehumidifier gives mold exactly what it wants — a dark, damp, enclosed space where nothing is moving and nothing is drying out.


So the liner that was supposed to protect your home ends up creating the perfect conditions for a problem you didn't have before.


That's not a scare tactic. That's just what happens.

A crawl space with white plastic vapor barrier covering the ground and wrapping around the support pillars and walls.

The Problem With "Looks Done"

At My Guys, we won't do an encapsulation without a dehumidifier. That's not a policy we put on paper to sell more equipment. It's a standard we hold because we've seen what happens when it gets skipped.


We've gone into crawlspaces behind other companies. We've pulled back liners and found what was growing underneath. It's not pretty. And the homeowner had no idea because everything looked fine from the outside.


A dehumidifier pulls the moisture out of that sealed space so it never gets the chance to build up. It's what makes the encapsulation actually work the way you imagined it would when you said yes to the job.


Without it, you don't have a complete encapsulation. You have an expensive liner with a problem waiting to happen underneath it.

What Done Right Actually Feels Like

When the job is finished — liner down, dehumidifier running, everything sealed the way it should be — you don't have to wonder. You don't have to think about what might be growing somewhere you can't see. You don't have to call someone back in two years to find out what went wrong.


The crawlspace is just handled. Clean, dry, and actually protected.


That's what a full encapsulation is supposed to give you. And the dehumidifier is what makes that real.

A crawl space with spray foam insulation on the rim joists, white vapor barrier walls, and a black ground liner.

Why we will not do an encapsulation without a dehumidifier

Not won't as in we'd prefer not to. Won't as in we'll turn the job down before we do it that way.


Because we've seen what happens on the other end. We've gone into crawlspaces that were encapsulated — lined top to bottom, walls and floor — and found mold growing behind that liner. The homeowner paid for work that looked complete from the outside and was failing on the inside.


That's not a job. That's a problem with a price tag on it.


When we do an encapsulation, we're not done when the liner is in. We're done when the whole system is working the way it's supposed to. The liner and the dehumidifier work together. One without the other isn't a complete job. It's half a job dressed up to look finished.

Book A Free Inspection Now

Your crawl space problems aren't going to fix themselves. But they are fixable. Let's get it done — the right way, permanently.

Or call us directly (217) 863-9559

When it's done right, you'll know the difference

If you’re not sure whether your crawl space has proper drainage or dimple mat, we can take a look and show you exactly what’s there.


No pressure. No guesswork. Just a clear explanation of what your crawl space needs — and what it doesn’t.


Schedule your crawl space inspection with My Guys Home Services today.

Based in

Mahomet, Illinois Serving all of Central Illinois.

Business Hours

Mon Fri - 8am to 5pm

Sat Sun - Closed

Crawl space encapsulation in progress, with white vapor barrier and orange text reading “Two-Day Crawl Space Encapsulation in Mahomet.”
By Jeff Robinson August 31, 2026
Day two. Mahomet, Illinois. And we're wrapping up. The crawl seal is down on the floor and walls. The dehumidifier is hung and running. The sump pump is reconnected and working properly. Spray foam was already done from previous work, so we didn't need to touch that.
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Day four in Decatur. We're wrapping up, and I wanted to walk you through everything we did. Four days ago this crawl space had a cracked foundation wall, missing wall seal in one of the rooms, and a moisture problem that wasn't going to fix itself. The existing sump pump wasn't cutting it either.