Hello Everyone,
I was wondering if anyone had any advice as far as proper usage of insulation. I am pulling down the old insulation in my basement, and want to put up some new energy efficient stuff with a higher R rating. Here is my problem. I have two different recommendations as far as how deep into the space between the joists the insulation should go. Meaning, I have 2×10 joists which are 14 inches apart, so should I buy insulation that goes up 8 inches into the space, or the full 10 inches and leave no room between the top of the insulation and the floor boards? I was told that there should be a few inches left in there to allow for air to flow and it helps with the heat convection, or should there be no space in there and have it fill the entire gap between the joists all the way up to the floor boards.
I know this may not be a great explanation, but I can answer any questions that might clarify the situation.
Thanks,
John
Replies
Greetings Johnny, As a new poster Welcome to Breaktime.
That particular subject has been addressed here on Breaktime many different times in the past.
In the event you fail to receive the information you desire, you will find an abundance of data in the archives.
If you scroll down in the lower left corner of your screen there is a search function that will take you to previous threads dealing with whatever you type in the search bar.
If you type in 'roof insulation' 'roof venting' or other keywords of the subject matter you'll get a supply of data from those old threads.
Cheers
Thanks so much! Yep, I've noticed there is a ton of info in the archives. I recieved one good response, and I'll get a little more from the archives.
Sorry I didn't reread your first post to see you were talking about floor insulation above your basement and not a ceiling/roof situation.
I take it you have an unheated basement. For ease of someone answering you here as much detail to your question will help others decipher the problem.
What part of the country are you located in?
I'm curious as to what kind of house you are insulating with an unheated basement and what kind of basement is it? Concrete floor?
A person with no sense of humor about themselves is fullashid
The house is in Seattle, and I was going to redo the old insulation in the unfinished section of the basement. I had a rat problem, and had to rip out a lot of the old insulation where they were nesting. Now that the old stuff is all gone, I just wasn't sure what the proper method was to filling the spaces again. Part of the basement is finished, but this section is unfinished with a concrete floor. I use it as a woodshop, mainly, but I figured having the proper insulation will help keep the upstairs warm.
I find it amusing that you received one good response, yet it has been deleated. Maybe Prospero thoght the rest of the world was'nt ready for that bit of wisdom.
Yeah, I thought that was a little unusual how the messages kept getting deleted.
Chances are it was the poster that deleted it for whatever reasons. Now you got me curious what was said.
Have you considered insulating the basement walls instead of the ceiling and turning the whole basement into a conditioned space.
Normally before insulation concerns are dealt with the first line of defense is stopping any infiltration of air. Common areas in cellars are between sill plate and concrete walls.
Stopping outside air flow will help maximize any insulation you do use.
I'm on a different computer now or I'd give a link for a site:'building science' that has a load of pertinent info.
A person with no sense of humor about themselves is fullashid
http://www.buildingscience.com
Edited 6/17/2005 7:37 am ET by RayMoore
Thanks, Ray!
http://www.buildingscience.com/
Thanks ray.
A person with no sense of humor about themselves is fullashid
Thanks for the advice about the air coming in. That has been a big concern for me in the basement. It is one of those old designs where they put a single car garage under the house, and this is the section that is now my woodshop. The other 3/4 of the basement is finished and I don't have any insulation problems, but the woodshop is letting heat out, and I need to make sure I get the cracks around the old garage door taken care of, as well as putting in good insulation between the floor joists.
As far as the other postings, I had one good piece of advice to think of the insulation like a pair of longjohns that go against your skin. In the same way that the longjohns go against your skin to keep the heat in, the writer said you need to put the insulation all the way up into the space in the joists, so that there is no air pocket left in there to cool things off.