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[DaveWertz]

Well I have been battling the cold lately. As you may all have read my other post about temps fluxing up and down in my house. The first half of the house was built in 1901, second half in the 50s or 60s. Now I had suspicion that a good bit of my heating problem is based off of poorly insulated house. Ive been doing some reasearch about spray insulation into walls (cant remember the name of the "new" materials used) and insulating the attic. Where would I benefit more by insulating? Im having someone come out and give me a quote to do the walls, not saying im going to but its def an option at this point. The attic is already partially insulated. And what about insulating the floors on the first floor? Would seem to be a pretty easy job for me to do that IF its benefical to do so.

[CountryBoyJohn]

Keep us updated on the cost of the injection insulation.  My upstairs could use some of that.  Thanks!

[chillyhiker]

Im considering that myself would like to know how they price it..sq footage or .?

[hondaracer2oo4]

I struggle with the same problems with my 220 year old house. I would suggest that you do as much reading about building science and insulation of old homes as you can. You biggest bang for your buck is absolutely the attic. Heat rises and if you can slow it down that is where you should put your money. Im not sure where you are located but my area is suggested to have R60. The other thing that you need to do in your attic besides insulation is air sealing. You need to seal all of the wires, light boxes, top wall plates, attic access hatch, chimneys etc to keep the air from moving into the attic which acts like a chimney sucking the warm air right out. I don't like spray foam in the attic because once it is done you can never remove it to do work later. I did alot of research and ended up going with Blown cellulose. I removed all of the old insulation and chaukled and expanding foamed all places for air to move from the living space to the attic space. After that I put down 8 inches of blown cellulose which filled the stud bays. I think layed over the top fiberglass batts to bring it up to R50. This has helped a lot with my heat loss. Old houses are difficult to insulated the walls properly without a whole lot of renovations. Old walls where designed to move air to dry out any moisture that made its way into it because of warm inside air condensing with cold outside air as it passed into the wall space because of inadequete air sealing. New houses when they are built are easy to air seal with plastic sheating because they can go right down to plywood floor sheathing and up the wall to a stud at the top of the wall plate. Old homes have boards for flooring and no top wall plate stud. Once again I don't like spray foam in the wall because you can't do any renovations later, it is permanent. What I have done with my walls is removed plaster and lathe. Insulated with fiberglass in the stud bays, then taken 1/2" foamboard and foamed, chaukled and taped all of the seams and the edges. I also foam and tape the electrical boxes to the foam board. After this I sheet rock over it. It makes for a R16 wall and is very air tight and seems to work well. Good luck with your research. Let us know how things work out.

[Wood Nutt]

You should get the most benefit from attic insulation in most cases.  If you can use spray on foam, it reduced air infiltration better than blow in loose or batt insulation as the spray on sticks to what it is sprayed on and seals up stuff better.  Its normallly quite a bit more expensive too.  If its one of the newer spray on foam insulations, that willl be tough in the walls w/out doing a major remodel unless there is nothing at all in the wall.  With the expanding foam type, they need to be careful or it will push the sheetrock/plaster/lath off the wall when the foam expands if they over apply it.  But, there are good products that can be forced inside existing wall studs other than expanding foam.  None of these are 100% effective because you never know where all of the voids are that were created during construction, remodel, etc over the years, but most reputable companies can monitor how much they are installing and get an idea if they are getting the coverage they need.   They usually price this by the square foot by depth of wall, or they estimate number of bales of insulation they will need and price it by the bale. 

On the attic, same deal with the spray on foam, you would probably have to remove the old insulation to allow the spray on foam something to stick to.  If you don't want to go to that effort, blow in insulation generally provides a better seal against air leakage.  Since you already have insulation, there may be a vapor barrier between the existing insulation and ceiling.  If you use batt insulation in the attic, when you add layers, it is recommended to lay each perpendicular to the last layer and that reduced air infiltration too.   Basically put in as much insulation as you can afford.

Floor insulation will normally be the most ineffective unless you are insulating a trailer house or modular without a foundation (i.e. skirted building).  If you have alot of tile floors, the floor will stay warmer with floor insulation but normally your crawl space and/or basement is partially conditioned anyway.

Attic and floor insulation is a DIY process unless you go the spray on foam route (that is possible too, but more difficult).  Around here, if you buy the blow in insulation for the attic, they loan you the blower if you buy the minimum amount of insulation bales.  Benefit with that system is buy what you can afford now and you can always buy more next year and blow more on top of what is already in the attic.

[robertj1]

I just had my 1911 2 story farm house injection foamed. What a difference. Wood usage dropped by 1/3. Down stairs was remodeled with fiberglass up stairs had blown in cellulose. Before the foam I could feel the cold walls and air blowing in through electrical outlets. Upstairs cellulose had settled. Cost was $3 square foot per wall space. No installation cost. Total was $4700. Brand was Applegate. Took the crew of 4 two days. One row of steel siding upstairs and downstairs above and below each window was removed. They will need to hook up to a 220 outlet and hot water. Something I wasn't told entill they showed up. Well worth it I think.

[coolidge]

What climate zone are you in? Do your research on that injection foam, it has a VERY high perm rating. the hot water is used to mix the foam, you will be getting 60% water injected in your walls. There used to be 4 or 5 injection foam companies around here, out of business.  Also be careful with the foam board and fiberglass, 1" may not be enough. Your dew point could very well be between the foam and fiberglass.
  Attic, 2" closed cell foam followed by 12" cellulose
  Walls, if your not tearing them out have a REPUTABLE company dense pack them.
  Basement/ crawlspace   2" closed cell foam from rim joist and down the wall too two feet below grade.

[DaveWertz]

Not sure about climate zone? Lol. I live in PA. See I dont feel any drafts coming threw the walls at all. Maybe doing the attic would better suffice. The one half of the house that was built after the first section has I believe 1" DOW. That also applies with the attic. Im not sure of the grade of insulation that is up there but half of it is complete. Its some pretty thick stuff. Looks to be 8" roll type fiberglass maybe. Now if I do the attic would it be better to seal up the around the edges real good or leave some room for air to move? I just coated my roof this summer so hopefully that helps a good bit.

[hondaracer2oo4]

You need to think of it like this. You have a conditioned space which is your first and second floor and possibly your basement. You need to air seal the "box" which is your living space so that air cannot escape from it. In the attic you will need to seal all of the penetrations that come from the conditioned living space box to the unconditioned(attic) space box. After that you will need to insulate above any area that is heated. Fiberglass batts don't work well in old homes for insulation because they need to fit snuggly in the joist bays without being compressed and without leaving any gaps. In new construction this is easy to achieve since everything is uniform and measured. In old homes it is often rough cut and not totally accurate on spacing. That is the beauty of using blown cellulose in the attic because it will fill all the void space evenly and effectively. I rolled my old fiberglass right back over the top of the cellulose. Your attic is an unconditioned space and should be in theory the same temperature as the out doors since you aren't heating it and it is outside the conditioned space.

[willieG]

in my century old home, i had no wood in theoutside walls...it was (from the outside) a layer of brick, a three inch gap, another layer of brick (the two layers tied together every few feet with a brick running opposite direction) and then the plaster right on the inside brick. i had htis gap filled with blown in insulation and it helped a lot but each time we saved a little money and redid a room i built new 2x4 walls on teh outside wall and filled them with spray foam. this old house heats easy now

[coolidge]

Whatever you do DONT USE FIBERGLASS   It is the worst insulation on the market.

[hondaracer2oo4]

Coolidge, why do you say that? I think fiberglass gets a bad rap because or poor installation techniques. It does need to be installed correctly by filling the void space without gaps and without compression. You also need to properly air seal before installing it. Fiberglass will not stop air movement at all and it's performance is severely impacted if air is allowed to flow through it. But theses problems are bad installations not the fault of the insulation.

[coolidge]

hondaracer,

     If everyone did the air sealing and other steps to enshure there would be no air to travel through the fiberglass then yes it would be a different story. www.sprayfoam.com/cnt/docs/17/ORNL_FiberglassReport.pdf
But, if a builder goes and builds a house, the insulation is the cheapest thing going in it. WHY?  I would much rather spend my cash on something i cant change after the drywall is up and be shure i have a tight home. Fiberglass also has been linked directly to cancer along with about everything else we have today.

   I looked at a house for a guy about a year ago, he hired a contractor to build it. I asked what he was doing for insulation. "Fiberglass i think" Shure enough a couple days later the crew was there and gone in two days. I happened to stop buy one day and asked if i could do a blower door on his newly insulated house, "shure can"   Huh what a mess, this brand new house was as leaky as one built in the 70s. We got 5234 cfm infiltration for about a 1800 sq ft house.   Builder had no time or budget for air sealing so the homeowner will pay for a long time.
   As you stated if done correctly, by being able to see both side of the cavity, fiberglass might be ok.    Sprayfoam and cellulose for me though.

[Boydz]

I am in the same boat and almost pulled the trigger in the injectable foam into the walls because it looks great for air sealing and filling voids, BUT, after researching the forums and doing more homework I decided against it because of the shrinkage that occurs and allows more air movement again. This retrofoam and many others can shrink as much as 1" in a stud bay leaving 1/2" gaps everywhere again within a few years. At that point the only way to get it out is to open the wall and remove it. I feel Dense pack cellulose is a much better long term solution and you can always go back and add more on top IF it settles to much. If done properly, I believe this settling will be minimal, which is why they Dense pack it to begin with.
I want to love the injectable foam, but the long term statistics prove its not worth the cost unfortunately.
My walls are still bare and I'm just using more wood until I feel confident that I can find an affordable long term solution.
I have air sealed the attic but need to update more electrical prior to stuffing it full of insulation. Id be lucky if its R16 now but at least its not venting as much as it used to prior to airsealing it.
I wish I could gut the place and spray foam the walls with real Icynene foam.
One shrinkage example - Spray Foam Insulation Shrinkage Problem In Wall of Existing Home