Adding Attic Insulation

I just bought a house and the house is cold. Neighbors suggested adding insulation to the attic. I went up there to check it out and there is insulation but it's matted down.

How much insulation should there be? The attic floor uses 2x6s. Should the insulation be no more than 6" high or can it rise up over the 2x6s? Keep in mind that I'm planning to cover the attic floor with plywood to use it for storage. I've heard that it's bad to compress insulation so should I put no more than 6" in since I know I'll be laying plywood over it?

Should I get faced or non-faced? Kraft or foil faced? The current insulation has a kraft face facing down (against the 2nd floor ceiling). Should I add non-faced or remove what's there and add brand new?

Any help would be appreciated. Thanks.

Reply to
JAG
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I have a question too along these lines. In my new house(1950) the 2nd story attic has blown insulation in it. I believe heat is leaking out through there because the wisconsin snow on my roof keeps melting very quick in some spots. I want to put rolled insulation up there too. ???faced ,unfaced,how thick ect ect any suggestions would help

Reply to
George Macomber

Cold house you mean turning up the thermostat wont help? You may have a legal issue. Where do you live , what zone , temp lows and highs ? Owens Corning and Johns Manville have good sites with R recomendations as does EPA . 6 inch fiberglass is apx R 21 in my mind not sufficent for even Fla Min Chgo area Zone 5 is r 35 and thats an old standard minimum . R 50 - 60 - 80 are common and used as most heat loss is up. Storage, reconsider unless you live where its warm . Insulate first.

Reply to
m Ransley

As always you need proper ventilation coupled with proper insulation. This link will provide you with the necessary R values needed. A WAG here, but I would guess you will need more than 6". You will have to sort your priorities of storage space or the continued loss of heat with potential structural damage (moisture) problems. If it were me, I would consider a shed for storage and get your insulation up to par.

Owens has a attic blanket R-25 that can go over existing insulation, you will have to determine if this will fit the bill or possibly blown insulation. You do not want an additional vapor barrier on the new insulation, one vapor barrier (as existing) against the living space.

Reply to
Duke

Joe fell out of the hole for the attic stairs and added:

Try this site at the US Dept of Energy

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Joe Ontario

Reply to
Joe

While too little insulation may be the problem, it is much more likely too little ventilation is the problem.

Adding more insulation, if you don't block the ventilation can never hurt.

Reply to
Joseph Meehan

If you really want to put down plywood for storage then your going to have to add 2x8 or 2x10 to the side of your rafters. I have 12 inches of blown in my attic and I live in Phoenix. Insulation is worthless if compressed or on some types if it is becomes wet. Forget the storage space, and put in at least 8 more inches depending on where you live snow country, maybe more. Call a couple of contractors and see what they recommend.

Reply to
SQLit

The more insulation, the better. Of course there's a practical limit. It can rise above the 2x6's (mine does). Do not compress the insulation. It will lose some R value if compressed. The ply you place down will help the insulation too, provided you don't compress what is there. Use non-faced insulation over existing insulation. There should be only one facing, and the facing should point toward (face) the occupied space. Don't forget about the cardboard or styrofoam "chimneys" for proper ventilation in your attic--very important.

Reply to
Phisherman

You could check the Building Science Corporation web site for insulation suggestions. The site has researched information, not opinions.

Have you checked leakage around windows and doors? What about the condition of your heating equipment and the filters in the ducts?

Tom Baker

Reply to
Tom Baker

If you are going to add plywood, then all you need is insulation even with the top of the rafters. Add if needed, don't remove, and don't add any faced material.

Reply to
George E. Cawthon

Reply to
George E. Cawthon

does that miraflex "encased" stuff count as "non-faced"?

the sadsacks that did my attic put it in upside down. I can't seem to find anyone willing to go up there and flip it over, add more where they missed spots, and then overlay (perpendicularly) some R25. The few insulation companies I called said the job is "too small". I'm on the verge of doing it myself, although I know it's gonna be a huge pain, and no fun....

Reply to
barb gee

No sure. I added the Pink Panther No-Itch stuff which has holes all over the batts which are encased in plastic. I guess its the plastic that helps (not eliminate) the itch factor.

Yeah, it's not a fun job. Tackle the job on a cool day, and wear all the protective clothing. If you can get a Tyvek "space jump suit" that would be ideal. Wear a mask too. While you're up there, caulk any opening you might find around light fixtures, pipes, vents, etc. My over insulation job took about a half a day.

Reply to
Phisherman

I live in Nassau County, Long Island, NY - the western end right near Queens. It's not usually very cold but it has been for the past 3 weeks. Usual highs are about 35 to 40 and lows are 25 to 30. Of course, this winter is not usual.

I have 3 zone gas-fired hot water baseboard. Only the bedroom zone gets cold. It can take 3 to 4 hours to heat from 65 to 69. The thermostat is in a hallway. There's some baseboard around the bend (the hall turns

90 degrees) and the bedrooms surround the thermostat. Each bedroom has a full wall of baseboard. The other 2 zones take much less time to heat the same 4 degrees - maybe an hour maximum.

The radiators all get hot so I don't think anything's wrong with the boiler. But I wonder if the thermostat is bad. I noticed the other day that it said 67 when it was programmed for 69. I walked away and passed by again 1 minute later and it read 69. I can't believe the temp in the hall went up 2 degrees in one minute.

This thermostat also controls the Central Air. It's a fairly new thermostat - Honeywell Magicstat 32.

As far as the attic goes, would it make sense to insulate the attic floor only till the top of the joists so I can put plywood down and then make up the difference by insulating the roof rafters? The attic would then be completely surrounded by insulation. Would this cause problems like moisture? Of course, I'd leave the area over eaves clear so the air can circulate.

There's also an attic fan with 2 vent stacks.

Reply to
JAG

What do these "chimneys" do? Are they the vented pieces that go over the eaves to allow air to flow? What if I just leave the eaves clear?

Also, as I asked in an earlier post: instead of putting more than

6" in the attic floor, can I just put the extra insulation in the underside of the roof? This will encase the attic in insulation. Is this something I don't want to do? Will it have a bad effect?

Also, if I put plywood down on the floor over 6" of uncompressed insulation, would the plywood covering itself add any benefit? You'd think the extra barrier between the house and attic would help hold the heat or A/C in the house.

I'd really like to use the attic for boxes and stuff but not at the expense of heating and cooling bills that are too high and a house that doesn't properly hold the heat and A/C in.

Another consideration is that my walls are probably not insulated or have minimal insulation. The house was built in 1964 but the siding was redone in the past 10 years. There's probably rigid insulation under the siding but I doubt there's anything in the walls. How much good will all this insulation in the attic do if I'm losing heat thru the walls?

Reply to
JAG

The chimneys or vents allow your attic to breathe. It extends the life of your roof and helps prevent ice damming, mold, and moisture buildup. You can leave the eaves clear, but the chimneys allow you to do a better insulation job.

Not something you want to do, unless your attic is living space.

Plywood, or wood for that matter, is a good insulator. But by weight-volume not so good (for an attic).

Usually, most heat loss is through the roof. You could have an infrared picture taken of your house to "see" where your home is losing heat. This will tell you where to insulate, and where not to insulate. Well worth the cost if you plan to stay in the house for several years. There's quite a bit of heat loss through windows too.

Reply to
Phisherman

Jeff I'm about 20 miles East of you.

I wonder if your hall t'stat for the bedroom zone isn't reacting to the heat from the rest of the house instead of the heat in the bedrooms. Usually a bedroom "zone" has a stat inside the largest bedroom.

Also, if there is a strip of baseboard in the hall the stat is located in. it might shut the stat off immediatley after it calls for heat because the baseboard is too close to the stat, tricking it into thinking the whole zone is satisfied when in fact only the hallway got warm while the bedrooms remain cold.

Reply to
HA HA Budys Here

Where does one find such a service?

What would I look under in the Yellow Pages, for example?

Reply to
Barb Grajewski

I'd probably start with "Photographers."

Reply to
Phisherman

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