Should I deck my attic?

[Praesul Presul]

Tat will shorten the life of your shingles by several years

Not if you have metal roofing or some ceramic.

 

[Jack]

That's why I asked all of this home owning stuff is still new to me. I was seeing if I should do it before I put down the decking. Thanks!

No problem at all, when did you buy your house?

 

[cnodie1]

June of this year.

 

[Bayoupiper]

Just noticed today that I need to have some blown in insulation put in my attic.



.

 

[Jack]

June of this year.

Good for you, I just got mine in April.

 

[BrandonLSU]

Why are you so angry at your attic that you would resort to violence?

 

[dixiejarhead]

RE: Shingles.

I've used spray foam on a few houses that we built. The theory behind shorting the lifespan of the shingles, is that the insulation holds the heat against the bottom of the shingle, thus shorting the lifespan. This doesn't happen. As stated above, the attic will stay a few degrees warmer or cooler than the main part of the house. A house that we built for my folks several years ago, originally required a 7 ton A/C, with the spray foam insulation in the walls and on the roof deck, the A/C requirement was dropped to a 4 ton. The house was about 3,800 sq. ft. and their electric bill was about $150 per month. Spray foam is very expensive, however, the cost savings will pay for the additional cost. I'll give you an example. The insulation for the parents' house cost $12,500 vs. $2,300 for batt insulation. The cost of the A/C, however, went from $20,000 to $12,000. With the new A/C and no batt insulation, the cost of the spray foam was $2,200. The savings on the electric bill of ~$150 per month paid for the balance of the insulation in just over a year.

Insulating your roof deck is only 1/2 of the equation, though so don't expect the same savings. In the most recent house that we build for the folks, we included a return on the A/C in the attic so that the attic is climate controlled as well.

You sir, are AWESOME! Thanks for that information!

 

[Bill Baldwin]

You sir, are AWESOME! Thanks for that information!

You, sir, are welcome.

 

[Hattrick 22]

Just got a 270 elcetricy bill in today on my 1600 square foot home and found this thread I'm giving it a bump for others I guess not to mention thanks for the provided information.

I'll just be trying to figure out if I should spend the extra money on the spray or go with the cellulose which I'm sure I can afford at the moment.

Any other input or ideas are welcome and thanks OP :-)

 

[Jack]

Hattrick, what is the height between the ceiling and the roof? Do you have any insulation now? How old is the house? How old/condition/type of current insulation?

 

[snapnek]

I have a spray foam rig and I also have a cellulose machine. I would say that if you can afford spray foam, do it! If that is out of your budget, then go with Applegate Stablized Cellulose insulation. The cellulose will cost less and still does a good job. The Applegate is better than the Home Depot brand, GreenFiber. Applegate has starch added and is activated when installed in the attic, this helps keep it from settling. Depending on the pitch of your roof, the cost of foaming it would be somewhere around $3,000-$3,500 and the cost to blow cellulose would be around $1,100. Hope this helps. Oh, and don't worry about the shingles wearing out sooner because of foam, that's been proven wrong. Shingle manufactures are all ways looking for a way to not warranty shingles. If you can afford the foam, do it! It also depends on how long you plan on living in this house. Good luck.

 

[snapnek]

Here is some very good information on building in the South.
http://joelstiburek.com/topten/south.htm

 

[Hattrick 22]

Hattrick, what is the height between the ceiling and the roof? Do you have any insulation now? How old is the house? How old/condition/type of current insulation?

It's 6 ft at the peak of the ceiling generally 4.5 to 5 foot anywhere else where plywood is layed.

As to the insulation itself it is yellowish looks like spray fiberglass I guess.

Our house is about 30 years old from what the wife says we've been in it for a little over a year and I wouldn't know how old the insulation up there is off hand. Doesn't look very new I guess.

 

[Jack]

I have a spray foam rig and I also have a cellulose machine. I would say that if you can afford spray foam, do it! If that is out of your budget, then go with Applegate Stablized Cellulose insulation. The cellulose will cost less and still does a good job. The Applegate is better than the Home Depot brand, GreenFiber. Applegate has starch added and is activated when installed in the attic, this helps keep it from settling. Depending on the pitch of your roof, the cost of foaming it would be somewhere around $3,000-$3,500 and the cost to blow cellulose would be around $1,100. Hope this helps. Oh, and don't worry about the shingles wearing out sooner because of foam, that's been proven wrong. Shingle manufactures are all ways looking for a way to not warranty shingles. If you can afford the foam, do it! It also depends on how long you plan on living in this house. Good luck.

This would've been exactly my suggestion, except the cellulose types, that's news to me.

It's 6 ft at the peak of the ceiling generally 4.5 to 5 foot anywhere else where plywood is layed.

As to the insulation itself it is yellowish looks like spray fiberglass I guess.

Our house is about 30 years old from what the wife says we've been in it for a little over a year and I wouldn't know how old the insulation up there is off hand. Doesn't look very new I guess.

If I was in your shoes, I'd probably go into the attic and seal all the holes in the top plates with foam before I did anything else. On a house that old I can pretty much guarantee nobody did it. Everywhere you see cable lines, phone lines, plumbing lines, and electrical there is a hole that allows airflow from the house into the attic and vice versa. My house is a little bigger than yours, I'm at around 2000 sqft. with cellulose, sealed plates and fixtures(where it wasn't too much of a bitch for me to get to), and an ac that stays at 75 and I haven't gotten a bill since I've been here for anything over 160.

 

[johnnybravo2550]

My home is 2400 sqft and 5 yrs old... attic is huge I cant even jump and touch the roof lol.. 14ft ceilings through out the whole house.. 1 layer of r30.... electricity bill was 130$ bucks last month...INVEST IN WINDOWS!!! Also during the day I keep my house at 75 degrees... at night 70 degrees... I have insulated the attic over my garage with r30 (pink stuff) .. insulated my garage door with a radiant barrier (silver bubble wrap stuff)...Home was built with insulation in garage walls.. Using my garage as a man cave... garage never goes above 80 degrees.. plan on getting a portable ac unit 12,000 btu and vent out through the wall to the outside...

 

[Hattrick 22]

This would've been exactly my suggestion, except he cellulose types, that's news to me.



If I was in your shoes, I'd probably go into the attic and seal all the holes in the top plates with foam before I did anything else. On a house that old I can pretty much guarantee nobody did it. Everywhere you see cable lines, phone lines, plumbing lines, and electrical there is a hole that allows airflow from the house into the attic and vice versa. My house is a little bigger than yours, I'm at around 2000 sqft. with cellulose, sealed plates and fixtures(where it wasn't too much of a bitch for me to get to), and an ac that stays at 75 and I haven't gotten a bill since I've been here for anything over 160.

Thanks for the info Jack.

Is there anything special to be aware of when spraying the cellulose I was thinking of doing some simple boxes to cover up my vents and light fixtures like the ones over the bathrooms. I take the rest of it is just work from one in to the other is there a certain thickness amount that the cellulose should be?

 

[bjeepin2]

you tube is your friend on all this insulation stuff
did my garage this year and it stays a lot nicer now put 8in of insulation then 1/2 OSB over it got 20 inch of insulation over the rest of the house.

 

[Jack]

Thanks for the info Jack.

Is there anything special to be aware of when spraying the cellulose I was thinking of doing some simple boxes to cover up my vents and light fixtures like the ones over the bathrooms. I take the rest of it is just work from one in to the other is there a certain thickness amount that the cellulose should be?

Depends on the R value you want, cellulose is about 3.5 per inch.

This article will give you more info than I'd be able to, just seal it all first. I had to go back and seal mine after(previous owner put the cellulose in) and it is so much harder to find what you need to fill with about a foot of snow up there.

http://www.greenbuildingadvisor.com/blogs/dept/musings/how-install-cellulose-insulation