Question about Insulating....

**prftstrngr** · 01-01-2009, 08:42 AM

I dont know if anyone here can help but any input would be greatly appreciated!

We own a 100+ year old home with a walk up attic. In the attic is that pink insulation which looks really old. My first question is does it lose R value? Or would newer stuff have a better R value and be more heat efficient?

Secondly.... Its cold up there...after all it is an unheated attic. And the insulation is just *there* nothing to cover it or anything. I think there should be some kind of vapour barrier over it but the problem is when we ask we keep getting different answers. One person says no dont do it...an old house is supposed to breathe and you will create more problems. And the next person says sure go ahead it will keep your heat in better! Does anyone have any insight on this?? Id like to make the house more energy efficient for us. The less I spend on oil and wood the better I like it!

**homesteadmamma** · 01-01-2009, 11:38 AM

Our home is over 100 years too. The best thing to do when it comes to being energy efficient is to change your doors and windows, especially in an old home. Once that is done, then insulation. We have insulation that has been blown in, in our attic and wasn't done properly when it was done. We are slowly adding more insulation so that we have a higher R value. We also didn't have any insulation in our walls. We stripped walls, dh made them into 6 inches instead of 4 and then we insulated. It was a lot of work, however so worth it.

**pbobber** · 01-01-2009, 11:38 AM

I have been told that as long as the insulation is not compacted, it does not lose R-value. I have also been told that any vapor barrier should face the heated side of the dwelling. I do not know if a vapor barrier is needed for attics. Mine doesn't have one. Also my previous home did not either. I put blow in insulation in that one.

**prftstrngr** · 01-01-2009, 04:47 PM

Thanks to both of you. Homesteadmamma our attic is a walk up so we cant use the blown in stuff. We are finding out there isnt much in the walls of the kitchen at least and as we renovate we will replace that. Some of the windows have been done and I really hate to replace the big wooden doors but I may have to at some point. My main concern is using the vapour barrier and causing too much moisture to stay in the house. yet without it I feel like the heat is going out thru the roof!!

**homesteadmamma** · 01-01-2009, 05:17 PM

The insulation should stop the heat from going out the roof. One way to know is if you have icicles hanging from your roof. We know exactly where the heat is getting out from our attic.

When we did our home, we found there was no insulation in any wall. The previous owner told us the house wasn't cold. Ummmm not if you have your heat set at 80. We thought maybe there were chips that had settled down to the main floor. There weren't even those.

**MoonMommy** · 01-01-2009, 07:16 PM

Ah...our house is old too and we also have a walk up attic. I am not sure how well it is insulated up there, but it can't be too bad since we don't have any icicles.

**geckoace** · 01-01-2009, 11:02 PM

R value is measured by inches check out
http://insulation.owenscorning.com/h...ols-resources/

i have found this helpful our house is 80 years old and one of our early 09 projects will be adding insulation to attic

**fashionhot** · 01-02-2009, 01:26 AM

I have the same problem as you guys

**Kaos Kitty** · 01-02-2009, 03:23 AM

Originally Posted by prftstrngr

We own a 100+ year old home with a walk up attic. In the attic is that pink insulation which looks really old. My first question is does it lose R value? Or would newer stuff have a better R value and be more heat efficient?

Secondly.... Its cold up there...after all it is an unheated attic. And the insulation is just *there* nothing to cover it or anything. I think there should be some kind of vapour barrier over it but the problem is when we ask we keep getting different answers. One person says no dont do it...an old house is supposed to breathe and you will create more problems. And the next person says sure go ahead it will keep your heat in better! Does anyone have any insight on this??

As part of my undergraduate degree in Architecture I just finished a paper on insulation and vapour barriers. I can help you out here. I'll try to explain without going on too much!

*Note: Info given is general and not meant to replace professional advice.*

A short explanation of vapour barriers

A vapour barrier has nothing to do with heat loss. What it does is prevent condensation from wetting your insulation and attracting mold and rot. Warm air holds more moisture than cold air. Without a vapour barrier, the moist warm air travels through the drywall and insulation until reaching cooler temperatures. The cooler air cannot hold as much moisture and is forced to release the moisture (condensation), making your insulation damp (making it less effective), and creating a home for mold and rot. Often people have leaks or stains on their ceiling and think the roof is leaking, when it's actually condensation, from "cold spots" created by uneven insulation. With a vapour barrier, the moist air never gets past the insulation, and therefore never cools down enough to condense.

In Canada a vapour barrier is installed on the inside (warm side - which from the interior is: drywall, vapour barrier, insulation, exterior cladding). Note: For those of you in Florida, vapour barrier is still installed on the warm side, but the warm side in your climate is outside! So the order from the interior would be drywall, insulation, vapour barrier, exterior cladding.

Some vapour barriers can also act as air barriers preventing heat loss from air exfiltration (leaking) but a vapour barrier and an air barrier are two different things. Air barriers are most useful in new energy efficient homes or tightly constructed buildings where air pressure can actually cause damage to the materials. Generally speaking, 100 year old homes have enough gaps in construction that air pressure damage is not an issue. That's the people telling you your house is "breathing", which of course is not very energy efficient.

An air barrier can prevent heat loss, but unless you plan to remodel your entire home to be completely sealed it would not be effective. In fact an improperly installed air barrier can be dangerous, as air pressure can force more water through a pin prick hole causing a problem spot, than would otherwise migrate evenly through without an air barrier. A vapour barrier on the other hand will let air through but not moisture.

What to look for

First, check the insulation in your attic, make sure it is evenly distributed and not compressed. As other posters have said, batt insulation can lose R-value if it is compressed. It can commonly be compressed in the eave areas (the lowest part where the roof slopes to meet the attic floor).

Think about where your insulated walls meet the attic, you want the insulation in the attic to completely cover/meet the top of the insulated walls, but it doesn't need to hang past the insulated walls (if your roof overhangs - because then it's not insulating anything). You can calculate the R-value of your current insulation based on its type and inches of depth. The key is even distribution. Uneven distribution means cold spots, which means condensation which equals mold. And of course be careful and wear protective clothing and mask when checking it out, older homes have used asbestos (dangerous if disturbed -professionals only), high formaldehyde content insulation or may not be up to current fire code standards. But clean, dry, uncompressed pink brand fiberglass insulation doesn't lose R-Value over the years, but it may sag out of position, creating cold spots. Even distribution is key!

If you don't have any vapour barrier, which would be located under your current insulation you should check for dampness or signs or mold. To prevent condensation issues the attic space needs to be the same temp. as outside with good outside air circulation (vents and a fan if needed). So if it's cold outside, and your attic is cold - that's a good thing! The outside air circulation is what allows any moisture that does accumulate to quickly evaporate and dry.

Hope this helps! If you don't have vapour barrier and want to add one to prevent future condensation issues consult a professional. (If you improve your windows and doors and air leaks you will be trapping more moisture in your home and may need vapour barrier even if you don't have mold/condensation issues currently). It should be in tandem with a wall vapour barrier ( creating a single sealed envelope) and making sure your wall insulation is even and adequate. Getting thermal pictures of your house taken in the cold season can help - it can cost a few hundred dollars but will show you exactly where you have insulation in your walls and attic and where you need help. It could save you a lot of money in utilities and head off any future moisture/mold issues. It will also show you where you need to stop heat leaks from electrical outlets ect, and exactly where your house is "breathing"! Good luck!

**Greebo** · 01-02-2009, 11:13 AM

One addition to Kaos Kittys EXCELLENT post on vapor barriers.

In a 100 year old house, you have got so many coats of paint on the ceilings that the paint itself is acting as a moisture barrier.

You can add insulation up top - and it'd be a good idea - just to increase the R value. NOT because it'll have lost R value - it wont. Time doesn't affect R value. Another layer of insulation int he attic - blown in or rolled fiberglass - will help.

However in a 100 year old house, you've got a lot of other places to be losing heat. The attic, already insulated somewhat, may not be #1 anymore. The window frames, door frames and walls are probably leaking like a sieve. I know they are in our 70 year old house.

**prftstrngr** · 01-02-2009, 12:11 PM

Thanks everyone -big help! I am passing the info onto my husband and he can figure it out. Greebo its a walk up attic so cant blow in insulation at all as its not just above the ceiling and actually the ceiling has no paint on it since it was one we tore out and replaced because of water damage before roof was replaced....so no layers of paint to help insulate...hehe! Thanks again for all the responses.

**Greebo** · 01-02-2009, 12:26 PM

Originally Posted by prftstrngr

Thanks everyone -big help! I am passing the info onto my husband and he can figure it out. Greebo its a walk up attic so cant blow in insulation at all as its not just above the ceiling and actually the ceiling has no paint on it since it was one we tore out and replaced because of water damage before roof was replaced....so no layers of paint to help insulate...hehe! Thanks again for all the responses.

Ok - in that case you can add a vapor barrier, but it'll be a pain.

Roll back the old insulation. Get 6 mil or better plastic sheets and snugly fit it into the cavities between the joists, getting it *tight* against the "floor" (the back side of the ceiling below).

Secure the sheets into the cavities. You can use a staple gun - but for a tighter fit, get 1x1 lengths of wood and cut them to fit in the cavity. Secure the plastic in place with the strips of wood, then put the insulation back in over the plastic.

Then to add insulation, run your next layer of fiberglass rolls perpendicular to the originals. For the second layer, get barrierless rolls, or REMOVE the vapor barrier (paper backing) from the roll before installation.

Here's a picture of how to set up the plastic sheeting to create the vapor barrier.

**prftstrngr** · 01-02-2009, 08:38 PM

Maybe Im confusing everyone....the insulation is on the roof side of the attic.....like between the roof joists and next to the roof boards and then shingles(outside). So if I walk up there its just wooden floor boards and the insulation is above my head. There is no insulation between the attic floor and our upstairs ceiling. So can I still put a vapour barrier? Lord Im blonde some days!!

**Greebo** · 01-02-2009, 08:59 PM

Originally Posted by prftstrngr

Maybe Im confusing everyone....the insulation is on the roof side of the attic.....like between the roof joists and next to the roof boards and then shingles(outside). So if I walk up there its just wooden floor boards and the insulation is above my head. There is no insulation between the attic floor and our upstairs ceiling. So can I still put a vapour barrier? Lord Im blonde some days!!

OH! OK in that case the vapor barrier definitely goes on the INSIDE side of the insulation. Put the sheets up over the insulation, staple it to the roof beams, and then use tuck tape or some other heavy duty, wide tape with a good strong adhesive (not painters or masking tape) to seal up the seams and the staple holes. If you're going to put in more insulation, you'll want to put that in first, secure it, and then vapor barrier. You want to keep moisture from the house from getting into the insulation.

After you do that, you can drywall over the whole thing to give it a finished look.

**prftstrngr** · 01-03-2009, 01:29 PM

Originally Posted by Greebo

OH! OK in that case the vapor barrier definitely goes on the INSIDE side of the insulation. Put the sheets up over the insulation, staple it to the roof beams, and then use tuck tape or some other heavy duty, wide tape with a good strong adhesive (not painters or masking tape) to seal up the seams and the staple holes. If you're going to put in more insulation, you'll want to put that in first, secure it, and then vapor barrier. You want to keep moisture from the house from getting into the insulation.

After you do that, you can drywall over the whole thing to give it a finished look.

And it wont cause too much moisture to stay inside? Personally if anything I think the house is dry inside cause we burn wood. I know they always tell you the attic needs to be vented but does that still apply when its like a room up there? But I dont want to risk getting mold either since the place is old....Im think renovating this will be my 25 year project!