Hunting Down a Solution to My Cold Bedroom Woes
It was a cold winter day when I noticed a heavy draft coming through the dog door and I got to thinking about how to stop it. But this is not the beginning of our story. The tale begins some years ago—never mind how long precisely—when my wife and I bought our house. We noticed over time that the summers were always warmer and winters colder, particularly in our poorly built bedroom. So the fight against the cold has been waged for quite some time. The battle escalated was when our baby boy was born and my wife and I were sleeping on the couch in the living room for two months because the bedroom was too cold. As with most issues that are important to me, they occupy a bit of my mind and consume a fair amount of my time; similar, as my wife put it, to Captain Ahab hunting Moby Dick. I don’t think “obsessed” is out of the realm of words used to describe what I felt about my quest to warm up this room and let my wife sleep in our bed again.
So, the draft from the dog door. The answer came to me while I was searching for DIY insulated dog doors. I found someone who had made a vestibule for their dog door. I knew I had to get in on the action. So I spent a weekend constructing a “doggie vestibule” with the wood I had laying around the house, complete with a removable roof, magnetic latching flap, and motion sensing light inside for night ops. I followed it all up with a layer of rigid insulating foam on the dog door’s single pane insert.
And yet the cold persisted.
Sealing Needed
When my mother-in-law visited, she mentioned that the sliding glass door wasn’t sealing and cold air was getting in between the two halves. It felt like someone left the refrigerator cracked open when I put my hand up to it. Turns out the dog door insert was preventing the door from closing all the way. I’m not sure how I missed this but this was a revolutionary find. I busted out the rigid insulating foam again and cut a length of it to fit the door.
Things were looking up, but there was still work to do.
A Frigid Realization
I noticed the floor was very cold, probably because of the density of colder air and the thermal mass of the concrete slab locking in the winter cold and acting as giant ice cube against our laminate flooring. Then I noticed that the baseboard definitely seemed colder than the rest of floor. I took some IR pictures to find out for sure. Turns out the space between the floor and wall was actually freezing, like 31.8°F freezing.
I asked around and Nick Baker, being a home renovation guru, said I could fill that gap with a spray foam insulation used for windows. I filled it up and it did help keep cold air from creeping in through the base boards, but not to the end that I had hoped. My wife and I ended up at Costco and we bought a giant area rug to cover the floor. That really helped. Now we’re getting somewhere!
Finally, I replaced the dog door flap into the house and stitched up an insulated cover for it to help keep the heat in and cold out.
These things seemed to help, but it didn’t quite fix it. My room temperature went up about 2°F to a cozy 66°. This is still not ideal for little babies.
Not a Fan of the Fan
As I walked into the room one day, I noticed the temperature drop right at the door from the hallway into the bedroom. It was about a 4°F drop across the threshold. I installed a small desk fan on the ceiling to move warner air into the room (since hot air rises, the ceiling is where the warmest air will be sitting). This worked to raise the temperature to about 68°F; warm enough for the family to move back into the bedroom. I still wasn’t happy, as this solution resulted in a huge black desk fan hanging in the hallway, and it was not something I was thinking of keeping up for too long.

An effective but temporary solution, for obvious aesthetic reasons. (Yes, engineers care about aesthetics!)
Reconfiguration for the Win!
Time to go deeper. I wanted to move around some duct work in the house because it seemed to be an afterthought while building the extension. Figured this would be a good time as it might solve the cold bedroom problem once and for all. After being talked out of just cutting holes in my ceiling, I took measurements at each supply register using an air velocity meter. After a review of the results, it was determined I did indeed need to move some duct work. Time to use my sawzall and SAW ALL!!!!
After ONE trip to Home Depot (a miracle for me, given my track record) and a day in the attic, I moved the vent from the neighboring bathroom to the bedroom. I still have a bit of cosmetic work to finish up, but it is sealed and our room now stays about 70°F, without an ugly black fan hanging from the hallway ceiling.
Unfortunately, it now gets a little warm at night for my wife and I, but that’s a small price to pay. I didn’t lose a leg like Ahab, and the baby is sleeping… as well as babies sleep.