replacement windows and insulation for attic question

[Bob Weisner]

Hi:

Going to be replacing some old windows in my house and need some suggestions as to which brands are good. The windows will be replacement windows and I will be getting all double-hung windows. The 2nd question I have pertains to attic insulation. I want to have my attic insulated with some blown-in insulation. How much insulation would be enough for an attic? Don't know if this matters, but my house was built around 1870 and has plank walls on the outside of the house underneath the sideing instead of regular plywood. Thanks for any suggestions.

Bob

[Ken Garlock]

Hi Bob. Regarding the insulation, since you didn't say what part of the country you are in, I am going to guess that you are in the northeast. In cold country the recommendation is R-40 for attics. Blown in fiberglass is the most common and probably the least costly. Fiberglass has an R value of about 3.2 per inch depth. Hence, I would go with about 14 inches for nearly R-45.

Two important things regarding insulation, first you can never have too much, and second it must be dry to be effective. Wet insulation is next to no insulation. This means that you need ventilation in your attic YEAR ROUND. Some people think they are "helping themselves" by closing up the attic in the winter. By closing up the attic in the winter you are trapping the moisture which infiltrates from the heated space below. The moisture in turn decreases the effectiveness of the insulation.

Regarding the windows, the most important part is to have thermo-pane windows. It is even better to have the "low E" thermo-pane that will lessen the transfer of radiant heat from outside to inside in the summer, and also help keep heat in the house in the winter. Most of your better window manufacturers will have "low E" windows. When we built our home, I used Marvin windows throughout. In the heat of a Texas summer, you can put your hand on the carpet where the sun is shinning, and you can't feel any heat.

One, last thought. You mentioned attic insulation, how about wall insulation! There are several types of insulation that can be blown into the walls of a house from the attic by drilling through the top wall plate. I would certainly check into the possibility....

[Bart Leetch]

I used to work in the insulation industry.

CELLULOSE IS NOT A GOOD OPTION.

It looses is fire retardant ability in approximately 5 years then is is just nothing more than ground up paper.

We vacuumed cellulose out of buildings the you could drop a match on & whoosh it would be gone in an instant. If you value your home, shop & family's life DON'T USE CELLULOSE. This is something we proved over & over & over again over the last 30 years. We had cellulose representatives come & try & sell us on using cellulose & we always politely listened to them & then gave them a demonstration by removing some cellulose from our vacuum truck & explaining to them it was over 5 years old & then dropping a match on it whoosh it was gone & the cellulose representative would quietly leave just as fast without saying much more than I guess I don't have a very good product to sell do I.

I flat don't care what the cellulose industry tries to tell you, I don't believe them & you shouldn't either.

They are in the business to make money & don't care about what happens to you 5 or more years away. I personally know of insulation contractors that will install cellulose (because the customer wants the cheapest insulation they can buy) but only after the customer signs a release the clears the contractor of any wrong doing if the structure burns down.


CELLULOSE PLEASE DON'T USE IT.

Rock Wool which is spun copper slag or Fiberglass would be a much safer choice.

[John Miliunas]

I used to work in the insulation industry.

CELLULOSE IS NOT A GOOD OPTION.

It looses is fire retardant ability in approximately 5 years then is is just nothing more than ground up paper.



Bart, as it happens, I've been planning on adding some more insulation in the shop ceiling space, but planned on using batts of fiberglass. After reading your post, I am now CONVINCED it will be batts! Thanks so much for the heads up to all concerned! That's an eye-opener. :cool:

[Terry Quiram]

I agree with Bart. CELLULOSE IS NOT A GOOD OPTION In my shop I blew in 20 inches of fiberglass. In another couple of years after all the settling I am going to blow in another 10.

Terry

[Bob Weisner]

Hi:

Thanks for all the replys! I did not know that cellulose insulation was that bad. When the new roof was put on my house about 6 years ago, they put a modified bituminous flat rubber roof on the back part of the house. Well, we have had so much snow this year that the flat roof sprung a leak, so we will have to repair the flat roof and the drywall that cracked in the ceiling causing the ceiling to start falling down.

As for insulation in the walls, when we had the house sided with vinyl siding, they put 1/2 inch insulation board on the outside walls. Still would have liked to have some insulation blown into the outside walls.

I don't know how thick the insulation was that they had blown into the attic. I watched the guy that was dumping the bags of insulation into the machine and they still had alot of insulation left on the truck that they did not use when the job was done.

Thanks,

Bob

[Lee Schierer]

I agree with the previous posts on cellulose insulation. Personally I would't take a bag of it home if they paid me to do it. I have 12+ inches of fiberglass batt insulation in my attic. Just make sure you leave air flow space under the rafters above the insulation.

Last summer, I replaced all the windows in my house. We used "Great Lakes Gold" replacement windows. They are 100% vinyl windows, with low E glass and work very well (seal tight, but move with finger tips when you want to open them). They tilt in and can easily be removed from inside for cleaning. On the -10 nights we had this winter, the window frames were warm to the touch on the inside. The glass was just cool. I estimate they reduced our heating costs about 10% this winter.

Make sure your installer caulks any framing he does and caulks the windows as they are installed. Too many contractors just slap the window in and it leaks air around it all winter.