Post Construction Insulating - Contractor Talk - Professional Construction and Remodeling Forum

Bud Cline · 05-18-2009, 09:26 PM

We want to insulate an older home from the outside before new siding goes on.

1.) Which is better blown-in (and why) Fiberglas or cellulose?
2.) Any tips, hints or reccommendations would be appreciated.

tommytwo · 05-19-2009, 12:43 AM

I'd use cellulose. Besides insulating, it can also help stop air infiltration. Up here, we usually drill a three or four inch hole, and run a 1" hose all the way to the top of each cavity. I know some people just put a smaller hole top and bottom, but I'd worry about not having enough density to prevent settling.

There's a little information starting on page 80 here:
http://www.state.mn.us/mn/externalDo...sota%20WFG.pdf

parts · 05-20-2009, 07:51 PM

I use a two and a half inch hole but use the same system as above. I believe cellulose is the best for this application. Fiberglass is a minimum two holes per bay as it can not be reduced down to such a small hose

Bud Cline · 05-26-2009, 07:50 PM

THANKS GUYS much appreciated.

tsunamicontract · 05-30-2009, 08:18 PM

what about cellulose settling? Have heard rumors of blowing insulation in the 2nd story of farmhouses and after a year it all settled down to the 1st floor wall cavities. What about slow expanding foam?

parts · 05-30-2009, 10:03 PM

Quote:

Originally Posted by tsunamicontract

what about cellulose settling? Have heard rumors of blowing insulation in the 2nd story of farmhouses and after a year it all settled down to the 1st floor wall cavities. What about slow expanding foam?

If done properly settling will be minimal. Slow expanding foam still is not cost effective and has it's problems of it's own along with all other insulation including a big one all the start ups trying to take advantage of the tax credits that have no idea what they are doing

neolitic · 05-30-2009, 10:19 PM

Quote:

Originally Posted by tsunamicontract

what about cellulose settling? Have heard rumors of blowing insulation in the 2nd story of farmhouses and after a year it all settled down to the 1st floor wall cavities. What about slow expanding foam?

One would hope that
the installer would take
a two story balloon frame
in to account with his methods.

Bud Cline · 05-31-2009, 10:26 PM

Quote:

tsunamicontract - what about cellulose settling? Have heard rumors of blowing insulation in the 2nd story of farmhouses and after a year it all settled down to the 1st floor wall cavities.

Can't see that even being possible.

neolitic · 05-31-2009, 10:31 PM

Quote:

Originally Posted by Bud Cline

Can't see that even being possible.

30 years ago, in balloon framed,
with different materials, and
different equipment, and
cowboy installers.....
it did happen.

Bud Cline · 06-01-2009, 11:28 PM

H-m-m-m-m-m! A rodents paradise for sure.

nEighter · 06-01-2009, 11:43 PM

that P2000 sounds like a more viable option

nEighter · 06-01-2009, 11:44 PM

Quote:

Originally Posted by tsunamicontract

what about cellulose settling? Have heard rumors of blowing insulation in the 2nd story of farmhouses and after a year it all settled down to the 1st floor wall cavities. What about slow expanding foam?

maybe not down to the first level, but cellulose does settle a hell of a lot.

tsunamicontract · 06-02-2009, 12:03 AM

I was actually thinking about in an old farm house. But great, now we have a painter getting his insulation answers from a painter

nEighter · 06-02-2009, 12:32 AM