How to Fix Interior Climate Control: Ask Anthony

anthony gilardi, home improvement advice

This week, Anthony shows a CafeMom how to properly ventilate her mudroom in order to fix a climate control problem that is making the interior walls "sweat" with condensation.

Ask HGTV's Anthony Gilardi your home improvement or home repair question TODAY in the comments below!


Today Anthony provides a solution to the condensation problem DogsMom explained in her previous post to Anthony

Hi, DogsMom,

You did a great job with your homework. I'm giving you an A+, and you get an official "Anthony Apprentice" badge.

Based on the information you sent to me, I was able to come up with a good, inexpensive plan to solve your problem.

For full disclosure, properly insulating all exterior walls, attic spaces, and crawl spaces under your house, along with filling all gaps around exterior windows and doors is not only the best way to fix/control temperature issues in your home, but it is also building code. Let's chalk this situation up to a problem that has been "grandfathered in," shall we?

With that being said, let's get down to work.


Square footage of room is between 225 and 250. We are rural; so except for fuel oil in the main part of house, we are all electric, therefore, electric space heater. The washer and dryer are just sitting, have not been used in a year. There is a vent hole cut in the wall but covered over until needed again. There is no attic, crawl space, or basement below. Two exterior walls. Two interior walls, one leading into an unheated kitchen. One interior door (kitchen), one exterior door. Two exterior windows.

Big dogs spend a lot of time in that room and are heavy breathers.


We are experiencing serious climate control issues to the point that are walls are sweating.


Before we do anything, let's address the two windows and exterior door. Properly fill all/any gaps in and around the area. Silicon caulking, or with larger gaps, expandable caulking works well around windows. Weatherproof around the exterior door's top and sides with weather stripping and install door sweeps to the bottom (if you need help with this, write me back).

Now we have the room somewhat air tight. Good start.

Question now: how do we vent an airtight room?

Well, I always explain to my Anthony Apprentices that you need to think of your home as a living breathing entity. Not a joke, material like wood, concrete, asphalt, etc. all breathe on their own. Think of them as lungs. Without a mouth or a nose, the lungs will not work.

Add humans and large "heavy breathing" dogs to the mix, and you have a high level of CO2 in the air. Without an escape (ventilation) and proper climate control, we create condensation. Or, as we love to put it, "sweaty walls." LOL.

What we need to do is give this room a mouth and a nose.  

There is a building code that states, when a closed-in "livable" room is a certain size, it must be vented, by power, to the exterior (much like an interior bathroom with no windows). Since you have electricity in the room already, this is not as big of a job as you would think. By replacing the existing ceiling light with a powered fan/light combo, you will not have to add a new light switch. I found a website for you that has different styles and prices of fan/light combos.

NOTE: Make sure the vent ducts properly travel to the exterior (much like a washer/dryer vent).

Because of the size of the room and the unheated adjoining rooms, this is only the first half of the solution. We also need to create an interior airflow from room to room.

We need to install some vents in the interior walls. These vents do not have to be powered and are very inexpensive. I found a website that has many interior vent options/prices to fit your budget.

FOUR (4) of  these vents need to be installed in your interior walls in this manner: TWO (2) in each interior wall, in line with each other, one vent should be installed one foot down from the ceiling and the other one should be installed one foot up from the floor. The same with the other interior wall (much like the vents of a utility room). See sketch below.

laundry room sketch

One more additional yet optional installation to consider would be to change out the kitchen door with a louver door. See this website for a few louver door options.

Okay, so we essentially gave the room a nose and a mouth to work with its lungs.

I know it sounds like a lot of work. However, if you take it step by step and follow the process carefully, I know you can do it.

I do suggest you consult an electrician to install the powered vent in the ceiling, but other than that, this is a DIY project.

Don't forget — I will always be here to help you and walk you through the process. You are not alone. I'm very proud of you already.

And since you like empowering yourself, you will be interested in my new web series: "Master Your Domain"

I can also be contacted through my website if you need me for further instructions.

-Anthony Gilardi 

Need advice on a do-it-yourself home repair or improvement? Leave your question for Anthony in the comments below, and he'll respond in a future post.


Previous Ask Anthony posts:

BATHROOM: Fix a Leaky Toilet

BATHROOM: Fix a Noisy Toilet

CARPENTRY: Basic Carpentry 101

DO-IT-YOURSELF: Top 10 Toolbox Essentials

DRIVEWAYS: Repave a Driveway

GREEN: Find Non-Toxic Construction Supplies

ELECTRICAL: Run Electrical to the Garage

ELECTRICAL: Fix Popping Circuit Breaker

EXTERIORS: Fix a Leaky Rain Gutter

EXTERIORS: Strip Chipped Paint off a Concrete Porch

EXTERIORS: Deal With a Mouse Problem

FLOORING: Refinish Hardwood Floors

FLOORING: Fix Slanted Floors

FLOORING: Remove Carpet & Sticky Adhesives

HEATING, VENTILATING & A/C: Thermostats 101

HEATING, VENTILATING & A/C: Install an Additional Thermostat


INTERIORS: Fix Cracked Ceilings

INTERIORS: Understand Types of Wall Anchors

INTERIORS: Choose Wall Anchors for Furniture Safety

KITCHEN: Troubleshoot a Broken Garbage Disposal

KITCHEN: Fix Unhinged Cabinet Doors

KITCHEN: Deal With a Sink Disposal Clog

LAUNDRY ROOM: Remove Your Washing Machine Agitator

LIGHTING: Remove a Broken Light Bulb

PLUMBING: Fix Slow-Draining Sinks & Tub

PLUMBING: Fix Foul-Smelling Sink Drains

PLUMBING: Drainage 101

SEASONAL (SUMMER): 10 Summer Maintenance Tips for Your Home

SEASONAL (SUMMER): 6 Ways to Conserve Energy This Summer

SEASONAL (FALL): Prep Your Home for the Fall Season

SEASONAL (WINTER): Winter Heating 101

WINDOWS & DOORS: Fix Sticky Screen Door

WINDOWS & DOORS: Weatherproof Doors & Window

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