Is the drafty floors in my 12-year-old home a design flaw by the builder and is there a way to insulate behind the soffiting or between the joists to improve energy efficiency?
Hey there! So, I’m new to this forum and I could really use some help. I’ve noticed that my upstairs bathroom is not very energy efficient, and I suspect that the floors might be the culprit.
My bathroom is right above the breakfast nook downstairs, and there’s this soffiting (marked with a red arrow) that seems to be letting in a lot of cold or hot air between the floors. Whenever it’s windy, I can feel a draft around the baseboards in my bathroom.
I’m wondering if this is a design mistake made by the builder (my home is relatively new, only about 12 years old), or if there’s a way for me to insulate behind the soffiting or between the joists myself. I’m pretty handy, but I could really use some guidance or advice on how to tackle this issue.
Sure, we can remove the soffit and add insulation towards the outer wall where the bathroom is. The insulation should have backing facing you. The soffit allows air to flow through the roof to prevent overheating. Also, let’s paint that door frame to eliminate drafts in the bathroom.
I have a hunch. Maybe they forgot to add sheathing on the wall when they extended that bump out. The soffit on the bump out is vented just like the rest, but it doesn’t serve a functional purpose. You can replace it with solid material to reduce wind flow in that area.
You could also seal it inside the soffit to make it blend in with the rest of the house.
Consider cutting a hole in the breakfast nook ceiling for further examination. Your suspicions seem valid. If the opening allows air through the soffit vents, you’ll see into the framing. Insulate, board up with tyvek, and repair the drywall. If not, investigate the walls or bathroom floor. Good luck!
Take off the soffit and inspect it. It might require sheathing and/or sealing. Seal the inside with plastic and add insulation. It should be a simple fix, possibly just a day’s work.
I had to remove my soffit and fill all the gaps with foam insulation. Front and back in various parts of my home. The builder really made a mistake.
That bay’s roof ought to have been constructed as a warm roof, meaning it is insulated similarly to the living space. Right now it is a cold roof, where it is vented to the outside to prevent moisture and heat accumulation. If you remove some of the soffit, you might determine if an insulation professional could fill the gaps with spray insulation. However, any plumbing or electrical components in that area might make it more complex. Get an insulation expert to provide an estimate and ensure they explain their process. Then you can decide if it’s something you can do on your own.
One common issue I have noticed is that the rim joist was not insulated before it was enclosed, leading to drafts. How is the rest of your second floor?
Yeah, I had the same situation with my bathroom floor above the bay area being cold and drafty. I fixed it by tearing out the ceiling, insulating the bay and kitchen with r30, and it totally solved the problem.
It’s important not to obstruct the airflow through the soffits because it could result in larger issues in the future. I believe the wall behind the porch roof may not have any insulation between the yellow line and the red arrow. You can purchase an Infrared camera gun at Home Depot to locate the cold spots.
Well I notice the vented soffit ….where is the roof vent or else that vented soffit won’t be effective ….is there sufficient insulation in that roof
In order to insulate, you might need to remove the soffit. Make a cut in the bottom of the fascia metal and bend it down to access the soffit.
Cut out a hole in the roof of the bump out, blow in insulation, and then install a vent over the opening.
You have the option to take off that piece of siding and drill a 3 inch hole to add blown in insulation. There is a special tool made for removing the siding.
However, the air passes directly through that insulation. Essentially, you are only filtering air at that stage. Using spray foam would prevent air infiltration.
It seems like they cut corners when it came to exterior insulation.
Points out that insulation doesn’t prevent airflow. House wrap is what stops airflow. Insulation helps to regulate the temperature inside by preventing cold and heat from seeping in.
Regardless of the approach, believes that corners are being cut!
12 years ago, they used to not seal the joist band where the roof is attached. The air coming into the soffits probably just goes between the joists. It really depends on the construction crew and whether they used house wrap and OSB sheathing under the vinyl. Take out the soffit and check. The pieces are held by the trim lip. I would recommend using big foam cans and a foam gun to seal it all up. Also, apply some white enamel and paint the door molding before the door jamb needs to be replaced.
You’re probably correct. I would suggest putting up some OSB boards to cover the opening. I would also recommend adding insulation inside the wall first.
Invest in a flir thermal camera. It can show you where the heat loss is occurring. It’s possible that insulation was not properly installed in the walls.
You might also be able to borrow one from your nearby library.
Like I mentioned before, using a thermal camera is the best way to find out. The entire northeast corner of my house had a similar problem.
How about checking the other side of the house that runs parallel to this area? Are there any exterior soffits or similar cold spots indoors?
Soffits are important for ventilating the main roof attic. That could be causing the problem.
In my opinion, the best solution would be to access the rim joist and insulate it with spray foam. This will require you to open up the ceiling downstairs for access. Some have suggested using a thermal camera to pinpoint any drafts before cutting into the sheetrock. Personally, I prefer to first inspect the area with a small hole and a camera light, or a peek hole. If you notice that the joists are not insulated, investing in spray foam kits is a good idea. It will save you the trouble of mudding and taping later on.
Alternatively, professional insulation companies may be able to use spray foam through small access points, which could be a worthwhile option to explore.
Are you positive it’s the floor that’s letting in the cold air and not the attic? Try placing a couple of hygrometers around the bathroom on a chilly, windy morning to detect temperature and humidity variations. This should give you a clear answer.
Consider using spray foam for insulation. Radiant floors are also a good option.
The soffit pieces typically interlock (similar to aluminum siding) and are quite easy to remove if they are not securely attached. Try taking out one or two pieces to inspect the area above. Is there an exterior wall behind the soffit, or does it lead straight into the house? This could explain the cold air in the bathroom. If it’s just a few support joists penetrating the exterior wall, filling the gaps with foam sealant should suffice.
This issue needs to be fixed. It’s probably as simple as removing the soffits, spray foaming the joist band, and then putting the soffits back. This should have been addressed in a indirect way during construction.
That bay needs to have a solid soffit and be properly insulated, since there is no ventilation in the roof. Remove the soffit, replace it with a solid one, and fill it with blown-in insulation before adding the final piece.
Mentioned the same thing. What was the reason for using vented soffit on a bay?
The bay window and cupola must have been constructed after the main frame of the house. It’s like an extra addition, so there shouldn’t be any ventilation from the bay into the second-story bathroom. I’ll need to check the plumbing.