Home>Discussions>INSULATION & HVAC>Insulating walls on 85 year old 2 1/2 story Colonial!
7 posts / 0 new
Last post
85 Year Old Colonial
Insulating walls on 85 year old 2 1/2 story Colonial!

Hi everyone, I have recently purchased an 85 year old 2 1/2 story colonial, with lath/plaster. Being that old you know there is no insulation. I want to remove all from the outside facing walls (from the inside) exposing 2x4 studs and install R13 faced insulation. Started on the second floor and looked down the studs and it looks like it goes all the way to the first floor. Can I inject/spray a fibrous insulation down the cavities between the studs and not be concerned about a thermal break problem? Or is this entire insulation thing a non beneficial endeavor?
Thanks Jim

george
Re: Insulating walls on 85 year old 2 1/2 story Colonial!

I am facing the same issue on an 82 yr old colonial 2.5 story that closely resembles the Archie Bunker house from All in the Family show. Just like yours, mine has wood lath, plaster the whole bit. My house is a balloon frame construction with walls made of 2X4 rough cut timbers and from the basement I can see all the way to the attic if you peak into the wall cavities. The foam insulation guy I spoke to said if I DIY the insulation, put a fire block between the studs at about 7 to 8 feet apart going up. He also advised to check with local code (I am in Queens NY) but typically a piece of 2X4 can be used or some people will use pieces of drywall stacked to the dimensions of a 2X4. For the slow rise foam stuff you make a hole in the plaster wall 1/3 the way up from the fire block and drop in the hose till it rises then go another 1/3 till you reach the top. The alternative is to remove all the plaster and spray it in like a new construction. I may end up using a combination of both since the plaster on one wall is in really bad shape anyway. But I will use the slow rise stuff where the plaster is good and I want to keep it.
Since my attic rafters are 24" on center I think I will almost have to use the spray stuff. I dont think fiber glass comes in 24" bats.
The Spray it Green web site has some videos you can watch and that may give you some other ideas.

Timothy Miller
Re: Insulating walls on 85 year old 2 1/2 story Colonial!

Hi quick get bids for blown in cellulose in the wall cavities of your homes. It is a great insulator and works great in balloon wall construction. R-13 is not enough if you are going to insulate add more(cellulose will be higher in the wall cavity)in most all parts of the country. Consider adding blocking in the basement between the floor joist if you can see up into the wall cavity 2by6,8,10,12 what ever size you have the blocking creates a fire block. Easier is to install rock wool batt insulation -Rolux Safe and sound (check out their web video for fire resistance) is common brand name and it has a great fire rating easy to cut like fiberglass an is friction fit so easy to install. The top of the wall on balloon construction usually has a plate but can you see down yours at the attic? if so what ever insulation you need to cap the top or the walls chimney just sucking the heat out of the house- cap with wood or if using cellulose it stops air flow by its own density > Note fiberglass does not.

canuk
Re: Insulating walls on 85 year old 2 1/2 story Colonial!
85 Year Old Colonial wrote:

Hi everyone, I have recently purchased an 85 year old 2 1/2 story colonial, with lath/plaster. Being that old you know there is no insulation. I want to remove all from the outside facing walls (from the inside) exposing 2x4 studs and install R13 faced insulation. Started on the second floor and looked down the studs and it looks like it goes all the way to the first floor.
Can I inject/spray a fibrous insulation down the cavities between the studs and not be concerned about a thermal break problem? Or is this entire insulation thing a non beneficial endeavor?
Thanks Jim

Let's answer your last question first --- it's absolutely a beneficial endeavor to add insulation. It's really not that expensive ( depending on material used )--- you will pay see a payback in reduced cost to condition the home--- doesn't cost a dime to maintain once in place.

Yes, you can blow in a loose fill insulation such as cellulose down the wall cavity.
If there is no blocking midway down the wall this would make it simplier. It would also be a good idea to block off that opening between each stud bay for two reasons :
1 - fire stop

2- will help with enhancing the insulation performance by reducing air movement.

Now , the million dollar question -- does your home have Knob & Tube ( K&T ) wiring?
Houses of that vintage have a good likelyhood of having K&T wiring unless it has been replaced at sometime.
K&T is not allowed to be covered with insulation

george
Re: Insulating walls on 85 year old 2 1/2 story Colonial!

Fortunately, the K&T in my house was removed and upgraded back in the 50's.

connie1405
Re: Insulating walls on 85 year old 2 1/2 story Colonial!
canuk wrote:

Let's answer your last question first --- it's absolutely a beneficial endeavor to add insulation. It's really not that expensive ( depending on material used )--- you will pay see a payback in reduced cost to condition the home--- doesn't cost a dime to maintain once in place.

Yes, you can blow in a loose fill insulation such as cellulose down the wall cavity.
If there is no blocking midway down the wall this would make it simplier. It would also be a good idea to block off that opening between each stud bay for two reasons :
1 - fire stop

2- will help with enhancing the insulation performance by reducing air movement.

Now , the million dollar question -- does your home have Knob & Tube ( K&T ) wiring?
Houses of that vintage have a good likelyhood of having K&T wiring unless it has been replaced at sometime.
K&T is not allowed to be covered with insulation

the 2milliondollarquestion: If I HAVE knob and tube wiring, how should one insulate?

connie1405
Re: Insulating walls on 85 year old 2 1/2 story Colonial!

The 2 million dollar question, If I HAVE knob and tube wiring, how can I Insulate? My exterior is cedar shake and sandstone.

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.