[Huggins90]

Hello,

We are renovating our 1600 sq ft. house. It is stripped to the studs and joists. There was no insulation at all anywhere in the house. The question is what is the best quality and most cost affective insulation to go back with. I was thinking just bat the walls and blow in the attic insulation with baffles on the sides. However, I am wondering about possibly using rigid foam? Is this a good idea, how would you go about doing this? I've seen someone on youtube cutting rigid foam then spray foaming it in place around the edges....dumb? I cannot afford to spray foam the whole house and due to keeping the historic windows, I'm not sure it would be worth it anyway. Also, brands for blown in insulation would be helpful. Also, I've heard mixed opinions on whether to use kraft paper backed or unfaced. I am in Zone 3, Southern Oklahoma. Thanks for any advice you can give on these matters. Electricians and plumbers are starting this week so insulation will be coming up soon!

 

[danpik]

There are going to be a lot of different oppinions on this so you may have to wade thru some of it and come up with what you think will work best for you. I have heard not to use a vapor barrier... use a vapor barrier...blown in insulation is better ... batt insulation is better...spray foam...well you get the idea.

One of the most important things to consider when doing this is that the outer envelope should not have any air leaks. Air being allowed to move into the insulation pulls the trapped heat out of it making it less effective. If there are any air leaks, get them sealed up before the insulation goes in.

Personaly, I would go with Batt insulation with a 4-6 mil poly vapor barrier. In the attic I would go with the same as I am not a big fan of blow in only because I hate having to dig thru the stuff if you ever have to work up there. Be sure to seal up any pritrusions (wires, Pipes) leading up into the attic as well. Keeping the heat from getting up there will go a long way in keeping the house warmer.

These are just my opinions. You do need to research this on your own some to find what you will feel most comfortable with.

Question...Do you have to keep the "historic" windows or is this something you want to do to preserve the look of the house. There are a lot of good options out there for replacements that have the "old" look with all the benefits of new windows.

 

[Huggins90]

To answer your question, yes. The home is in the historic district of our town and the old windows are desirable. I'll put storm windows on them eventually which will help a bit.

I have heard, in this area, install the facing to the outside, rather than inside? Yes or no...?

So by the outer envelope you mean something like a housewrap? Or just the penetrations in the sheathing, floor, ceiling, etc...It is asbestos siding now, int the future if we were to add vinyl siding, should we housewrap it first, then side it? Can you have multiple layers moisture barriers? (one being the insulation facing, the other the old builders paper barrier between wood siding and asbestos siding, and the other being the housewrap? Would this trap moisture somewhere in those layers?

Thanks!

 

[md2lgyk]

I know this is a DIY site, but I have a suggestion that was given to me by the inspector when my wife and I were building our log home (literally, almost entirely by ourselves). Because of his position he could not recommend any specific businesses, but said to check out a local one "with a number in its name." That turned out to be 84 Lumber. They have a subsidiary company that does only insulation. Their quote was quite a bit less than I had calculated for materials alone. And they insulated the entire house in a day and a half. Best deal I got on the entire project.

 

[Gary in WA]

No v.b. or vapor retarder; http://www.buildingscience.com/docu...heet-310-vapor-control-layer-recommendations/

House wraps are vapor permeable, Tyvek is very open (58 perms). R-30 for your location, ceiling; http://publicecodes.cyberregs.com/icod/irc/2009/icod_irc_2009_11_sec002.htm

Danpik was right-on with air-sealing first; http://www.google.com/url?sa=t&sour...sg=AFQjCNHwd56o0AxLi8-V03E5cMUmwWATQw&cad=rja

http://www.conservationtechnology.com/building_design.html#MoistureTransmissionPathways

Gary

 

[Huggins90]

Great links and great advice.

I am definitely going to seal everything before drywallers come in then I think I'll insulate exterior walls with unfaced batts, then, after drywall is up, seal penetrations in drywall in attic and walls, then blow in insulation in the attic. Still not sure on whether to go with attic cat owen's corning or green fiber. Any thoughts on which is better? Seems like green fiber is denser, and when crawled through, seems to stay relatively puffy. If the pink fiberglass gets stepped on, it squashes down tight and loses all it's R value. I know attics aren't made to be crawled in, but I'm a DIYer...I always have a project...!!


Any ideas on crawlspace sealing versus vented?

 

[bbo]

Great links and great advice.

I am definitely going to seal everything before drywallers come in then I think I'll insulate exterior walls with unfaced batts, then, after drywall is up, seal penetrations in drywall in attic and walls, then blow in insulation in the attic. Still not sure on whether to go with attic cat owen's corning or green fiber. Any thoughts on which is better? Seems like green fiber is denser, and when crawled through, seems to stay relatively puffy. If the pink fiberglass gets stepped on, it squashes down tight and loses all it's R value. I know attics aren't made to be crawled in, but I'm a DIYer...I always have a project...!!


Any ideas on crawlspace sealing versus vented?

here is a great article on crawlspaces

http://www.buildingscience.com/docu...d-codes/view?topic=resources/cond-crawlspaces

i would definitely condition mine ( if i had one instead of a basement)

 

[Gary in WA]

I usually recommend cellulose over fiberglass and Roxul over fiberglass. Actually, anything over f.g., at least the low densities; http://www.diychatroom.com/f98/biggest-loser-fiberglass-insulation-90438/

Your milder climate is gentle on low density f.g. compared to colder climates: http://www.homeenergy.org/show/article/year/1993/magazine/77/id/910

Use good cellulose; http://s84919.gridserver.com/compan...t-all-cellulose-insulations-are-created-equal

It air seals any spots you missed (unlike f.g.); http://bct.eco.umass.edu/publications/by-title/cellulose-insulation-a-smart-choice/

The tests (f.g. cubed low density (0.50); http://docserver.nrca.net/technical/401.pdf

From Sweden (2007 ?)- 9.4 = 0.59 density, Fig. 5, pp.7; http://web.byv.kth.se/bphys/reykjavik/pdf/art_085.pdf

Your Atticat; See chart; R-30----- 12"/11.5" thickness = 1.04 x 0.504 = 0.53# density....http://www.r-prollc.com/Documents/Atticat_Insulation_Fact_Sheet.pdf

hmm, same density as the tests, lol.. But, your climate is not that cold, even though you don't get convective looping like a colder climate, at least use a housewrap over it (or 2-3" blown cellulose) if the attic is vented to protect from wind-washing; up to 40% R-value loss with a wind outside a vented attic and 10-12k (0.62-0.75 medium density) insulation, pp.5; http://www.aecb.net/PDFs/Impact_of_thermal_bypass.pdf

Compare your Atticat at R-30/11.5" = R-2.61 per inch to blown cellulose in that chart of last link, compare cell. thickness required;then compare prices... if you need more links for pro cell (in a fire, fibers filtering in house through thermal barrier, etc.), nay f.g., let me know; about 2 dozen left in my library.

Gary
PS. yet another link; http://books.google.com/books?id=7H...esnum=8&ved=0CDcQ6AEwBzgK#v=onepage&q&f=false