Could this also be a sign of missing/inadequate insulation in the walls?

Yes Kim, the insulation (or lack or inappropriate installation of such) is a huge factor here. One job of the insulation is to keep the interior of the wall from getting cold enough to cause condensation, and with frost forming, that means the interior wall temperature is below freezing. Somewhere there is an air leak or an uninsulated wall. I am a Certified Home Energy Rater and a Certified Building Shell Specialist. I am afraid that we see this issue pretty often. Finding a professional who can perform infrared thermography will help to narrow down the problem and validate insulation issues without invasive investigation. As Tim says, this is a symptom of a problem that can lead to serious issues. The source of the problem needs to be found and fixed.

We don't have frost on our walls, but we have condensation forming in certain spots on the ceiling against the exterior walls. This only seems to happen when it gets really cold outside (below 10 degrees F). We have blown in insulation in our ceiling. Could solving this problem be as simple as crawling into the ceiling and adding more insulation. Our neighbors have a similarily built house and are experiencing the same thing even though they just had extra insulation blown into their ceiling.

When attempting to replace stairs that had rotted leading to the basement, I ran into problems. I used the standard method of constructing stairs and found they do not work. I need adequate head room from my landing going down to the basement without making the stairs too steep. Can you help me.
The rise is 70 1/2" - landing to basement floor. From the bottom of the backwall to the basement floor is 91 1/2". The distance to the wall from landing to back of stairwell is 52 1/2".

We have icynene insulation in our 2x6 exterior walls (4-5" nominal) and in our attic (5-6" nominal). Living in Iowa, we've had a cold December and now even a colder January - below zero many days. First our problem with frost started in our master bath, in corner of shower area near the ceiling. It's a northwest wall and very cold. Now we're seeing frost in various places throughout the house. Even interior walls near the ceiling once again. We're hoping the vendor can make this right - this is our 2nd year in the house!

We just put up insulation in a new addition and we found frost forming between the plywood and the insulation. There is no heat in the addition, no siding on yet, and we put up a vapor barrior. Will we need to tear it all down? What kind of problems will this cause? And how do we fix it?

This is Sharla of Hathmore Technologies (hathmore.com) again. I see these new comments and thought I'd try to help address them.

Everett - your and your neighbor's problem may have to do with your roof truss system. Many times the roof trusses are placed directly on the exterior walls and there is not very much room for attic insulation over the exterior walls. If you also have icicles form along the edge of your roof in the winter, this would be another indication of this issue. The warm air from your house escapes because the insulation is not thick over the walls. The heat melts the snow on the roof which re-freezes when it hits the cold soffit. Icicles are pretty, but very damaging to roofing and roof decks. First, get to the edge of your attic over your exterior wall and make sure the wall is fully sealed - seal the drywall and any gaps you can find with caulk. Then put as much insulation over the entire top plate of the wall as possible and see if that helps things.

Lisa - again I would recommend Infrared thermography. Foam insulation is fantastic, but only if installed correctly. I have seen installations where the wall cavity was not completely filled and wiring and plumbing penetrations were left in the top plate allowing the attic air into the home between the insulation and the drywall. Also, the plumbing is usually installed before insulation, so that shower corner may not have been fully insulated. An experienced thermographer can help you locate the problems.

Nicole - It would be good to know what state you live in. A vapor barrier may be a very bad idea. Where is the vapor barrier in relation to the insulation, drywall and sheathing (the board behind the siding)? It sounds as though warm air is finding its way through your insulation and condensing on the sheathing, then re-freezing causing the frost. All penetrations that can allow interior or exterior air into the insulation should be sealed (outlets, switches, plumbing, cable or air conditioning runs, etc.) If you are in a very cold northern climate, your vapor barrier should be on the interior side of your insulation (just behind your drywall) and if you live in a warm, southern climate it should be on the exterior of your insulation. If, however, you live where it is cold and dry outside in the winter and warm and humid outside in the summer (a mixed-humid climate) you do not want a vapor barrier at all. You need to let the water vapor escape to both sides of the wall. You do want an air barrier, but it should be vapor permeable.

Well, that's enough rattling on for now - I hope it has been helpful!

Sharla,

I'd like to thank you for your comments on this post. Your advice is much appreciated. I had run across an article about Infrared thermography and had planned on requesting the testing to be completed on our home... but didn't want to seem to over-confident when I talked with the vendor about my suggestion. They'll be by later this week to talk with us.

Again thanks. I'll be sure to post the outcome.

Lisa

This is my third winter in my new house. I like Lisa have frost on my walls. We have the setting on our humdifier set to the lowest setting and the temperature is set to 68 degrees on the main floor. Our formal living room which faces west has hit lows of 46 degrees on days when it is 20 degrees outside. My son's room which is on the second floor has the same problems. We have two other rooms on the second foor that have started to get the frost. The one room is an interior wall that adjacent to an attic that is above the master bedroom. Each year the condensation/frost metastizes and now we have mold. My builder has brushed me off so I am now pursuing taking my builder to court. We have been told by other contractors that the furnace on the second floor is too small and of course there are many voids in our insulation. We hired a home inspector who has a thermal image camera and he indicated if he takes pictures he would have over 1500. We do have many photos though of the frost/condensation. Are there building publications that list the standards for both the furnace and insulation? I am trying to find out for myself how do you determine the correct size of the furnace and how many registers should be placed in large size rooms? Those very cold rooms are also the very hot rooms in the summer. Lisa good luck to you too.

I get frost only in a one section of my cellar. The outside temp is very cold and I do not have heat in my cellar. The cellar is not finished and only has unfaced insulation. If I remove the insulation from the area, the frost goes away. I would like to have a play room built in the cellar.

I Louise