When they built my house it had an unfinished attic with a OSB floor. It is designed to be finished, and we have been doing that. I have always wondered about the insulation UNDER that floor. It looks to be white fiberglass loose blown insulation about 10" deep. It completely fills the cavity. From what I can see, all penetrations have a bead of orange foam around them. However, I know there are can lights buried under there too far to see. There is no vapor barrier, poly or kraft paper. What prevents the underside of the floor from becoming a condensing surface? Is it the heat from the house keeping the underside of the OSB so warm that it cannot. I know there are thousands of other houses built this way, so I can't be the only person in this boat...
Silly question...
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Not silly but we have learned since that was built. What year?
Yes, the underside of the OSB is a condensation surface but hopefully they have sealed most of the air passages. Unfortunately probably not all as that takes an expensive effort, extra time.
I assume that unfinished attic is fully ventilated thus as cold as outside. But even a small amount of moisture will not be an issue and will dry through the OSB to that attic.
In most cases you do have a vapor retarder from the paint on the ceiling and in most cases they are advising no VB just good air sealing. Citation available.
As for the recessed lights they should be IC and AT rated (insulation contact and air tight) although the air tight is not perfect.
As for finishing the attic into living space it is not grandfathered so check current requirements to be sure you are up to speed. Don't know your location so can't guess. Pictures also help.
Bud
Yes, the underside of the OSB is a condensation surface but hopefully they have sealed most of the air passages. Unfortunately probably not all as that takes an expensive effort, extra time.
I assume that unfinished attic is fully ventilated thus as cold as outside. But even a small amount of moisture will not be an issue and will dry through the OSB to that attic.
In most cases you do have a vapor retarder from the paint on the ceiling and in most cases they are advising no VB just good air sealing. Citation available.
As for the recessed lights they should be IC and AT rated (insulation contact and air tight) although the air tight is not perfect.
As for finishing the attic into living space it is not grandfathered so check current requirements to be sure you are up to speed. Don't know your location so can't guess. Pictures also help.
Bud
Every ceiling penetration I have found has a bead of foam around it. It was built in 2013. It is a modular cape built by a national builder. They have done most things right from what I can tell. I believe in my region the vapor retarder can be latex paint. The only thing I worry about was that I blocked under the knee walls with pieces of r-30 insulation when I added more insulation to the lower attic. I realize it is not a perfect air barrier, but it was what I had at the time. I fear I have made something worse trying to keep heat in. Climate zone 4 from the map. I have found no moisture by feeling around or by the "sniff" test. The only place I found a musty odor was in the joist bay above a bathroom that had a vent fan that was leaky.Not silly but we have learned since that was built. What year?
Yes, the underside of the OSB is a condensation surface but hopefully they have sealed most of the air passages. Unfortunately probably not all as that takes an expensive effort, extra time.
I assume that unfinished attic is fully ventilated thus as cold as outside. But even a small amount of moisture will not be an issue and will dry through the OSB to that attic.
In most cases you do have a vapor retarder from the paint on the ceiling and in most cases they are advising no VB just good air sealing. Citation available.
As for the recessed lights they should be IC and AT rated (insulation contact and air tight) although the air tight is not perfect.
As for finishing the attic into living space it is not grandfathered so check current requirements to be sure you are up to speed. Don't know your location so can't guess. Pictures also help.
Bud
Actually it is partially finished with insulation and hung, unfinished drywall. It stays quite a bit warmer than the outside temperatures. It never gets below freezing up there. It was a DIY project that started and was beyond my capabilities. I insulated the living space before I knew that insulation the roofline was the way to go. I am just going to pay someone to do it right this spring. I just don't want my house rotting down or something...Not silly but we have learned since that was built. What year?
Yes, the underside of the OSB is a condensation surface but hopefully they have sealed most of the air passages. Unfortunately probably not all as that takes an expensive effort, extra time.
I assume that unfinished attic is fully ventilated thus as cold as outside. But even a small amount of moisture will not be an issue and will dry through the OSB to that attic.
In most cases you do have a vapor retarder from the paint on the ceiling and in most cases they are advising no VB just good air sealing. Citation available.
As for the recessed lights they should be IC and AT rated (insulation contact and air tight) although the air tight is not perfect.
As for finishing the attic into living space it is not grandfathered so check current requirements to be sure you are up to speed. Don't know your location so can't guess. Pictures also help.
Bud
Zone 4A
A cape, they are a pain, I live in one. But I suspect they did a pretty good job or air sealing. One indicator is, did they include a HRV or CRV with the house? When a house gets too tight one of those or other fresh air method is required.
One of the problems with a cape is that roofline, the depth of the rafters. They need to be deep enough to install the required insulation and allow airflow from soffit vents to high vents (either gable ends or ridge vents).
Doing DIY without new permits is a risky path. I did some house hunting for someone wanting to relocate in this area and asked each building department is permits had been pulled for the work that had been done. I did not recommend an offer on any of those houses and I suspect the code office was in touch with the owners. Computers today make it easy to track everything.
Bud
One of the problems with a cape is that roofline, the depth of the rafters. They need to be deep enough to install the required insulation and allow airflow from soffit vents to high vents (either gable ends or ridge vents).
Doing DIY without new permits is a risky path. I did some house hunting for someone wanting to relocate in this area and asked each building department is permits had been pulled for the work that had been done. I did not recommend an offer on any of those houses and I suspect the code office was in touch with the owners. Computers today make it easy to track everything.
Bud
There were permits, they just don't inspect anything here except septic. I said DIY, but really I paid people to come in as I could. Every bit of work was done by licensed contractors in their field. The only thing I did was add insulation on top of the insulation in the lower attic, hang insulation in the kneewall and cathedral, and lay batts in the upper attic. The electrical was done by an electrician and any additional framing was done by a framer. I actually called an insulation company to come and remove what I did and foam the cathedral and cellulose the rest. They wanted $7K. We are at a standstill with the project right now. I wish I had someone just come in and do the whole thing at the beginning.A cape, they are a pain, I live in one. But I suspect they did a pretty good job or air sealing. One indicator is, did they include a HRV or CRV with the house? When a house gets too tight one of those or other fresh air method is required.
One of the problems with a cape is that roofline, the depth of the rafters. They need to be deep enough to install the required insulation and allow airflow from soffit vents to high vents (either gable ends or ridge vents).
Doing DIY without new permits is a risky path. I did some house hunting for someone wanting to relocate in this area and asked each building department is permits had been pulled for the work that had been done. I did not recommend an offer on any of those houses and I suspect the code office was in touch with the owners. Computers today make it easy to track everything.
Bud
Not trying to bust your chops, just need to cover the usual permit topic for you and the thousand readers who come after.
If permits were pulled and no inspection was done then a buyer in the future gains leverage over you because YOU cannot prove the work was done correctly.
Copies of all permits plus copies of all inspections are best. If no one called for an inspection you should have, it's your house and your investment.
Keeping records of all licensed contractors is also a good idea. Hiring a licensed contractor includes their insurance as part of the price. You also want the name and contact info of those insurance companies.
When doing DIY your camera is your friend. Take pictures of all work as it progresses.
Off mu soap box and no need to explain, I'm not part of your project. But i do wish you the best as a fellow owner of a cape. By the way I'm doing a deep energy retrofit on mine and results are impressive.
Bud
If permits were pulled and no inspection was done then a buyer in the future gains leverage over you because YOU cannot prove the work was done correctly.
Copies of all permits plus copies of all inspections are best. If no one called for an inspection you should have, it's your house and your investment.
Keeping records of all licensed contractors is also a good idea. Hiring a licensed contractor includes their insurance as part of the price. You also want the name and contact info of those insurance companies.
When doing DIY your camera is your friend. Take pictures of all work as it progresses.
Off mu soap box and no need to explain, I'm not part of your project. But i do wish you the best as a fellow owner of a cape. By the way I'm doing a deep energy retrofit on mine and results are impressive.
Bud
In my life I have never even seen an inspection in this area other than septic. There are two guys for the whole area. They mostly are concerned about flood plain.Not trying to bust your chops, just need to cover the usual permit topic for you and the thousand readers who come after.
If permits were pulled and no inspection was done then a buyer in the future gains leverage over you because YOU cannot prove the work was done correctly.
Copies of all permits plus copies of all inspections are best. If no one called for an inspection you should have, it's your house and your investment.
Keeping records of all licensed contractors is also a good idea. Hiring a licensed contractor includes their insurance as part of the price. You also want the name and contact info of those insurance companies.
When doing DIY your camera is your friend. Take pictures of all work as it progresses.
Off mu soap box and no need to explain, I'm not part of your project. But i do wish you the best as a fellow owner of a cape. By the way I'm doing a deep energy retrofit on mine and results are impressive.
Bud
For such a young house, I think you shouldn't worry too much or try to remodel already to your exacting standards. Not the same but similar is auto repairs. Some people wait until something breaks and some people research and ask and do preventative part changes. Although I am the latter:smile:, sometimes I wonder how much good I'm doing with part changes. But I wish I had changed the power steering pump because now I'm one car less, and both the parents and kids are demanding rides. As the saying goes, when it rains, it pours.
If the attic was partially finished, and removing that work and doing it again makes you happier, then fine. But if demolition hasn't started, and this is something I learned to force myself to do, step back, take a breath and rethink the necessity.
As for the resale value of evidence, it depends on the whole picture, neighborhood, street, how close to school, transportation, the usual factors. If a certain buyer is picky, that means just be wary of them. If a buyer brings up issues during closing process, example, means you can consider very low discounts which is not really that bad. I think most people are smart enough or maybe ignorant enough, to not become problems. Lack of inspection is not your fault or responsibility and sounds like the area problem, maybe, so something like that becomes a general issue and not your problem. The realtor or the local lawyer will have explanation for those, and don't let the buyer or anybody else make it into your problem. Realtor, yours or the buyers, example, may use such reasoning to influence the estimates, and as you say, everybody is in similar boats, so don't be swept into taking personal responsibility for the area's problems.
If the attic was partially finished, and removing that work and doing it again makes you happier, then fine. But if demolition hasn't started, and this is something I learned to force myself to do, step back, take a breath and rethink the necessity.
As for the resale value of evidence, it depends on the whole picture, neighborhood, street, how close to school, transportation, the usual factors. If a certain buyer is picky, that means just be wary of them. If a buyer brings up issues during closing process, example, means you can consider very low discounts which is not really that bad. I think most people are smart enough or maybe ignorant enough, to not become problems. Lack of inspection is not your fault or responsibility and sounds like the area problem, maybe, so something like that becomes a general issue and not your problem. The realtor or the local lawyer will have explanation for those, and don't let the buyer or anybody else make it into your problem. Realtor, yours or the buyers, example, may use such reasoning to influence the estimates, and as you say, everybody is in similar boats, so don't be swept into taking personal responsibility for the area's problems.
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