How do you keep a cold guest room warm?
Close the gaps first: put a draft stopper under the door, add foam gaskets behind outlet covers on exterior walls, and make sure furniture is not blocking the vent. Hang heavy curtains and close them at night. If the room stays cold no matter what, it likely has empty exterior walls or a thin ceiling, and insulation is the long-term fix before next year's gathering.
Thanksgiving week has a way of exposing every weak spot in a house. The guest room that sits empty most of the year suddenly needs to be comfortable for two or three nights. The kitchen runs hot all day while the back of the house stays cold. And with a dozen people coming and going, the front door seems to be open more than it is closed.
Here is how to get through the week comfortably, with fixes you can do before Thursday, and what to do about the cold room once the leftovers are gone.
Why is the guest room always the cold one?
Guest rooms tend to be the rooms nobody spends much time in, so their problems go unnoticed until someone has to sleep there.
They are often corner rooms, with two exterior walls instead of one. In many Central Kentucky homes built before the 1970s, those walls are empty. Some guest rooms are in additions, finished basements or bonus rooms over the garage, which tend to have thinner insulation or more exposed surfaces than the main house.
There is also a habit issue. Many people close the vent and the door in a guest room to save on heating. That works fine until the room is needed, and then the walls, floor and furniture are all cold and take hours to warm up.
What can you do in the next 48 hours?
You cannot insulate a wall before Thursday, but you can make a real difference with a few simple steps.
- Open the vent and the door a day early. A room that has been closed off for weeks needs time to warm up, because the walls and furniture are cold as well as the air. Start the night before your guests arrive.
- Clear the vent. Make sure no bed, dresser or rug is blocking the supply register. Furniture over a vent is a common reason a room will not warm up.
- Stop the draft under the door. If the guest room has an exterior door, or sits next to one, put a draft stopper or a rolled towel along the bottom.
- Seal the outlet covers on outside walls. Inexpensive foam gaskets go behind outlet and switch plates and cut the cold draft that often comes through them.
- Hang heavier curtains and close them at dusk. Glass gives up heat fast after dark. Even a temporary blanket over a curtain rod helps.
- Add layers to the bed. An extra blanket and a mattress pad do more for a guest's comfort than you might expect.
- Use a space heater carefully if you need one. Follow the manufacturer's instructions, keep it well away from bedding and curtains, and do not leave it running unattended or overnight unless the instructions say it is designed for that.
How do you manage the rest of a full house?
A house full of people behaves differently from an empty one. A few adjustments help everyone stay comfortable.
The kitchen and dining room will run warm. An oven running for hours plus a crowd of people adds a lot of heat to one end of the house. Resist the urge to turn the thermostat way down. If the thermostat sits near the kitchen, the rest of the house may get cold. Lower it a degree or two at most, and open interior doors so air can move.
Keep the front door traffic in check. Every time the door opens, cold air rushes in. If guests are coming and going, a mat inside and a quick close of the door help more than you would think.
Watch the rooms at the far end. Bedrooms and bathrooms at the opposite end of the house from the kitchen may get cold while everyone gathers in one place. Leave their doors open so air can circulate.
Use ceiling fans on low, in reverse. Many ceiling fans have a switch that changes the direction. Running them slowly in the winter direction pushes warm air down from the ceiling without creating a cold breeze.
What about the bathroom and the overnight hours?
Two spots catch hosts off guard. The first is the guest bathroom. Bathrooms on exterior walls, especially ones with a window over the tub, can feel icy first thing in the morning. Leave the door open overnight so the room shares heat with the hallway, and put a bath mat down so bare feet do not land on a cold floor.
The second is the middle of the night. If you set the thermostat back while everyone sleeps, the guest room, which was already the coldest, drops the furthest. For the nights you have company, consider a smaller setback or none at all. A degree or two of savings is not worth a guest waking up cold.
What is the cold guest room telling you about your house?
If you did everything above and the room is still cold, that is useful information. It usually means the room is losing heat faster than the system can replace it.
The usual causes are empty exterior walls, a thin or disturbed patch of attic insulation above the room, air leaks around the window frame and rim joist, or a cold floor over a garage or crawl space. Most cold rooms have more than one.
Here is a simple test you can do while guests are in town. On a cold evening, lay a hand flat on the inside of an exterior wall in the guest room, then on an interior wall. A clear temperature difference often means the outside wall has little or nothing in it.
How do you fix the cold room for good?
The lasting fix is insulation and air sealing, and the work can be done any time, including right after the holidays.
Empty walls can be filled with injection foam from the outside through small holes that are plugged and patched. Your drywall or plaster stays in place, and the room does not need to be emptied.
A thin ceiling can be topped up with blown-in insulation. Central Kentucky is in climate zone 4A, where ENERGY STAR recommends R-60 for an attic with no insulation and R-49 when adding to 3 to 4 inches.
Air leaks around the attic hatch, light fixtures, plumbing and the rim joist can be sealed before new insulation goes in.
ENERGY STAR estimates that air sealing and adding insulation in attics, floors over crawl spaces and basement rim joists saves homeowners an average of 15 percent on heating and cooling costs. The comfort difference in a cold room is usually the first thing people notice.
Why is right after Thanksgiving a good time to look into it?
Because the problem is fresh. You just spent a week noticing exactly which rooms are cold and when. That is exactly what an inspector wants to hear about.
The coldest part of the Central Kentucky winter is still ahead. The National Weather Service puts Lexington's normal January low around 25 degrees, and the cold room you noticed in November will feel worse by then. Injection foam and blown-in insulation can both be installed in cold weather, so there is no need to wait for spring.
And if you host again at Christmas or next Thanksgiving, the guest room will be ready.
Get every room ready for next year's gathering
Enjoy your Thanksgiving. Once the guests head home, request a free inspection from USA Insulation Central Kentucky, and we will look at that cold room, check your walls and attic and give you a written estimate so every room is comfortable next time the house is full.
