attic insulation and how to work with it in a remodel

Does anyone recognize this insulation? This is in an attic of a house built in the 1950's and remodeled in the '70s. A nice little outbuilding has mineral wool insulation done in bats...it is labeled. From looking at other pictures on line it doesn't look like asbestos, we thought. There is a small attic window and it appears that the upper layer of insulation is bleached out and deeper down still pink...would that mean it is loose fiberglass?

here's a couple more pics a little closer....

Yes, this is a "spun glass" and virtually worthless as an actual "lofting" high R insulation. It was developed further after WWII for insulating in desert regions against "heat gain" and was never really that great (still isn't for a number of issue) and insulating against cold and heat loss...That has not stopped a multi trillion dollar global industrial complex from marketing to the unsuspecting permies...

If I do use a "manufactured" insulation 95% of the time (or more) it will be a mineral wool.

Regards,

j

Thanks Jay, I was hoping it might be mineral wool since that was used in an out building, but spun glass is workable for us, at least compared to asbestos.

This doesn't belong in 'natural building' really...maybe someone could move it to a more appropriate forum....we need a 'reworking old houses' forum or something

I'm linking this thread to a couple really good ones with a lot of insulation discussion.... https://permies.com/t/31241/natural-building/Eco-friendly-insulators-high and this one https://permies.com/t/31490/natural-building/Vapor-permeability-material-suggestions-humid

Any suggestions for living with it? The attic is begging to be floored and finished off into a room...really a nice space, but what to seal off the fiber glass with before adding a floor?

Hi Judith,

I hate asking questions as part of an answer...Sorry about that...

As for laying a floor the first thing I may suggest is make sure it can take the load!

Many old attic floors where not designed to take second floor live loads. Now that just mean (for the most part...but not always) that the floor just may be a bit "springy." In other cases it means things could break.

There is usually no reason to remove old insulation unless it is invested with mice or other critters, and even then only those badly contaminated section have to be dealt with. I am not sure if you will be insulating above your head, or if this will be a "cold space" or "3 season space??" So if just laying a floor, then there isn't any real "sealing off" of the insulation other than the flooring material chosen itself...wood is most common...and green fresh wood is just fine?

Just to actually get some "real" insulation up there beside that "pink icky stuff" perhaps a layer of mineral wool board then your flooring, which personally I tend to"float" and not try to fasten down, but I tend to like to "joint" things and let wood move the way it always wants too...

Hope that helps...Let me know if I can get into anything else about it...

Regards,

j

You will have to remove that insultion, and if you want a room there you must insulate the roof. The bats here must be very thick and depending on your climate I might put one seceond layer of insulation on the inside. If you don't mind noise you simply can nail floorboards on.

Jay C. White Cloud wrote:Hi Judith,

I hate asking questions as part of an answer...Sorry about that...

As for laying a floor the first thing I may suggest is make sure it can take the load!

Many old attic floors where not designed to take second floor live loads. Now that just mean (for the most part...but not always) that the floor just may be a bit "springy." In other cases it means things could break.

There is usually no reason to remove old insulation unless it is invested with mice or other critters, and even then only those badly contaminated section have to be dealt with. I am not sure if you will be insulating above your head, or if this will be a "cold space" or "3 season space??" So if just laying a floor, then there isn't any real "sealing off" of the insulation other than the flooring material chosen itself...wood is most common...and green fresh wood is just fine?

Just to actually get some "real" insulation up there beside that "pink icky stuff" perhaps a layer of mineral wool board then your flooring, which personally I tend to"float" and not try to fasten down, but I tend to like to "joint" things and let wood move the way it always wants too...

Hope that helps...Let me know if I can get into anything else about it...

Regards,

j

I don't mind questions at all, Jay....this is in a house that we are almost up to closing on and just checking out some last minute stuff. We were thinking of the attic space as some storage and an extra sleeping space for company...spring and fall it would be comfortable, I think, with no ceiling insulation. I like the idea of the mineral wool board and then boards...it won't ever be 'finished' in an normal sense...mainly a floor that is a barrier between us and the fiberglass.
Thanks for the input...checking out the load bearing ability being most important

Angelika Maier wrote:You will have to remove that insulation, and if you want a room there you must insulate the roof. The bats here must be very thick and depending on your climate I might put one second layer of insulation on the inside. If you don't mind noise you simply can nail floorboards on.

Thanks, Angelika...We were thinking floor first and then somewhere down the line if needed we would insulate the roof. I would rather the fiber glass wasn't there but we are going to try to work around it rather than attempt a removal. If it happened to have been asbestos we would not buy the house because of the difficulty of removing safely.

Angelika is correct with the best advice on the thread, it is best to remove the FG insulation reason being it is probably not up to 2015 code as far as old anti fungi, blowing agents, and most importantly fire retardants. Ceiling/roof insulation should have a flame spread index not to exceed 15 and smoke-developed index of 450. If that is going to be an occupied space the ceiling becomes a fire separation and needs 5/8 fire rated drywall or other approved material. Fire blocking on walls that may be old balloon framing is also required.

Your other choice as you guessed correctly is to seal all the rafter bays and flooring. The reason this is typically done by the best designers with loose fill batts is once a moist air loop gets in from air paths it circulates unlike a dense cellulose or mineral wool allows. When FG glass gets wet it's r-value gets knocked down 20-30% and it now has what it needs for microbials. Building Science Corp proved all this most pro architects know this. There is no win-win situation....If you do not seal those nasty partials become airborne and get into your indoor air quality through the grannies causing all kinds of health issues. If the vents are balance properly you should feel a good breeze on a windy day. I do not see the proper number of roof vents in the photos. There s/b 60% low, 40% by area on the roof. If not that is a breading ground for microbials and loss of r-value. If you seal to keep particles a bay now you run the risk if moisture gets in it has no way to dry.

I'd rip it all out regardless if I finished it or not. I'd spray a borax mix all over the places and make sure my ceiling bays were all sealed, then I'd lay down a mineral wool batt. Those look like at least 2x10s so you should around r-30 ish there and sound proofing for a finish floor, Roxul makes safe and sound batts with up to code ratings. 2x10s can easily take 10PSF which is storage load. 20PSF (dead and live) easy no issues. If they are tied to rafters the rafter spans have been adjusted, if on joist hangers/rim joist or birdsmouth no issues. If 16 OC joist use a APA rated plywood or T&G.

Angelika is correct again in that your roof rafters need to be at least 2 x 12's with a mineral wool board and batt your looking at ~ r-36(batt r-30, board r-6) which is minimum in your Z5 climate. If not your heating bills go through the roof Then you have to find heating/cooling ducts that may over load your HVAC. The return line can take FG particles with it to IAQ if the bays are not sealed. A minisplit is a good solution. Wait to you see the cost on all that, not pretty!

I don't mind questions at all, Jay....this is in a house that we are almost up to closing on and just checking out some last minute stuff. We were thinking of the attic space as some storage and an extra sleeping space for company...spring and fall it would be comfortable, I think, with no ceiling insulation.

I love it!

Excellent. I think "sleeping attic" or second floor "cold rooms" are a wonderful traditional space to bring back into vogue. Here in Vermont they were commonplace in vintage buildings, and made occupants appreciate the "snuggle" fresh clover beds with there down comforters and wool quilts...with a nice open window to enjoy the fresh air... Also a great way to avoid "taxable living space" in many states as these aren't considered in the same context as "heated rooms."

Your guest would appreciate the ambiance, I think.

I probably shouldn't have used the word 'remodel' in this post at all. What we are really interested in doing is living as best we can with what we buy into....this house has many pluses for us along with what we hope are livable issues. So, we are going to keep things as simple as possible.

Jay, that is exactly how we were looking at this..a nice ambient space...finished off as simply as possible.

Terry, thank you for your in depth post. ....the house has no central heating and air and we don't plan to have it...we'll heat with a wood stove and because the home was built in the 1950's some thought was put in to air flow....9 foot ceilings and porches and lots of windows. We may eventually add an attic fan and that is part of the reason to 'seal' in the fiber glass and floor the upstairs. the attic does have vents in each end along with the window seen in my picture above. I suspect the aluminum window was added along with the insulation in the seventies. Many rural homes here have no insulation.

Thank you all very much....after we are in the house I plan to start a more in depth thread with more problems we come up against and better detail and pictures.

Terry Ruth wrote:your roof rafters need to be at least 2 x 12's with a mineral wool board and batt your looking at ~ r-36(batt r-30, board r-6) which is minimum in your Z5 climate. If not your heating bills go through the roof Then you have to find heating/cooling ducts that may over load your HVAC. The return line can take FG particles with it to IAQ if the bays are not sealed. A minisplit is a good solution. Wait to you see the cost on all that, not pretty!

We are zone 7 not 5 so we are still looking at insulated attic floor and not rafters I wondered why rafters need to be at least 2X12's? to hold the mineral wool boards weight or to hold enough insulation? no 'heating and air' ducts up there. Our cost of winter heat is usually the wear and tear on the chainsaw and our backs to cut and haul the wood....if it gets really cold we just shut off more and more rooms...no problem

The best "easy fix" for loose fiberglass insulation,  is to cover it with a layer of loose cellulose insulation.

 The cellulose material works as a partial air seal and rodents don't like it. It therefore improves the lesser material beneath.  Loose fiberglass allows convective currents to move heat through the material.  Small cracks can be filled with a latex caulking so that fiberglass particles don't sift down over time. Also,  good quality paint on the ceiling helps prevent infiltration.

 This is something that could be accomplished for as little as $200.

I like what you are trying to do...

Plow with the horses you got.

As for rafter size, it is one of those things like "floor joists." Much of it today has to do with "margins of safety" (I would add this is subjective and industry driven to statistical mean averages) and some esoteric "agreeance" on averages that all came together in the last 75 years to give us "deflexion minimums," (i.e. how "springy" a floor "CAN'T BE") and isn't just about whether a floor/roof can hold the weight it is subjected to. We have seen in the last 10 years alone countless vintage buildings over 175 to 220 years old that had all manner of floor and roof timber dimensions spanning some distances I did not even think possible.

Two year ago, for example, was a barn in Maine with rafters that stretch greater that 23 feet on 10/12 pitch that at the ridge was a little over 3" square and at the tails of the rafter where just under 5" square...all 2 feet on center...The range of"joist" and "rafter" sizes and spans is vast in vintage buildings with well proven with historic track records of great functional use and extreme exposures. Few would meet today's subjective "CODE" standards even though they have worked well for 200 years...The building industry is inundated with "subjective views" based on "averages" and "perceptions" and seldom on "impartial application evidence" alone, which more than has sound merits to follow and learn from.

Even within code parameters, there are other choices besides 2X stock, or I would have been out of business years ago...

Judith.

As it seems, nobody has noticed the Red top insulating blanket!

https://permies.com/t/50626/a/32749/IMG_0048a.jpg


Well, whenever i see the old gypsum, i fear that there will be some asbestos around.

http://www.mesothelioma.com/asbestos-exposure/companies/united-states-gypsum.htm

I would say, take some of that loose fill, and get it checked. Same for the red top.

It's not compulsory in the us, to have an asbestos repport, when you plan to sell a house? And that repport should be given to every potential buyer. That's the case in euroland now. Been a few years.

thanks for the link, Max...helpful stuff. The Red Top insulation says 'mineral wool' and is in an outside building. You've got me wanting to find the exact date of the remodel for this house though. I suspect it was in the seventies and am hoping it was more recent after reading the info in your link.
Do you suppose it would be rude to ask the sellers (the heirs to the house) how their parents died and at what age? We go look at their 'disclosure' today.

I was looking up RedTop Insulation that I came across while updating my grandparents lake cottage, that I just bought back after it having been out of the family for 25 years. The owner between us did little to no upkeep or repairs but added some shotty updates with shortcuts everywhere and obviously with no inspections. So when I can upon this site I was excited to learn that it isn’t a toxic material, like asbestos, nonetheless, with the age of it I’d want to remove it to verify there is no mold behind what was a stand up shower. Circa 1944. I see there are some very knowledgeable people that have commented here, which I find exciting because I have A LOT of work ahead of me and this will be an excellent resource for me to use during this project. I want this done right and to last another 100 years because I want it to stay in the family for generations to come. I hope to make lasting memories playing and watching my grandchildren at the beach like mine did with me.
I started with removing the original fuse box and updated with 220 and also put on a metal roof with a 50+/lifetime transferable warranty.
We had a stand up wall furnace that was removed and replaced with a non vented gas fireplace, it is NOT a ventless fireplace, so that is next to be repaired so it will now be a 4 season home/cottage.
I’ll keep watching and reading on my path to completion. Wish me luck-more to come.

Hi Alane and welcome to Permies! I'm not sure what Judith's results were, she may be able to comment.
I'm not familiar with the red top insulation, but it may be worth checking it for asbestos content. this page lists red top products and insulation blankets as potentially containing asbestos. Sometimes it's better to be paranoid than cavalier about things.
It's so nice for you that you have your family home back - good luck with making happy memories!