Learn me this not so old house: Episode - Insulation

Bought my first house (built in 1952, back when sex was safe and racing was dangerous...) last July. I wasn't sure how expensive it was going to be to heat (~2000 sq-ft, CT) through the winter. Well, for it being a mild winter, it wasn't cheap. We burned about 1000 ga of oil in the past 12 months...... Sucks.

So, I'm doing a few things to reduce me heating costs for this year. First, I picked up a pellet stove we'll be using on the first floor in the living room. This is where we spend most of our time and taking care of the stove isn't anything new since I also have one in the garage (heated garage FTMFW).

The other task to tackle is to insulate/reinsulate. The house has vinyl siding and has the foam insulation board underneath the siding, in addition to some old crappy insulation in the walls. We have a walk in attic upstairs that pretty much goes the length of the front side of the house. In the attic, the floor of the attic and ceiling of the first floor is uninsulated. What kind of insulation can I use here? I have a roof vent and air can pass from the walk in attic up to the proper attic. Now, there's a part of the roof at the front that I don't have great access to. More detailed: What kind of insulation can I use here? I think I'll have to blow it in since I can't actually reach in very far. Batted? Unbatted? Vapor barriers?

Great GRM DIY homeowners, bestow your knowledge to me.

Thanks guys

What is that part that is hard to reach? Is it just the soffit, or an entire room?

If it's a room, you can't blow it it. You will have to cut a hole through so you can get in there to do it properly.

What is a "walk-in attic" vs a "proper attic"?

Carpet and padding where you walk? Pink panther where you can, stapled in. Will a local utility do a free energy audit?

SVreX wrote: What is that part that is hard to reach? Is it just the soffit, or an entire room? If it's a room, you can't blow it it. You will have to cut a hole through so you can get in there to do it properly. What is a "walk-in attic" vs a "proper attic"?

I can't reach far into the soffit. The opening is only about 8 inches tall and it looks to be about 3 feet deep.

The walk in attic is the walk in on the second floor. I was calling the proper attic the one above the second floor.

Soffit= overhang. If it is a porch ceiling, etc. that is not over a heated area, it does not need insulating. If it is a cavity over a heated area, you need to cut the roof sheathing open high enough to get in there to work.

All of the heated areas need to be separated from the outside by insulation. So, the walk in area needs to be insulated at the floor, or alternately the roofline. The ceiling over the 2nd floor and the "proper" attic needs to be insulated, and so do the walls from this room to both the wall in area and the knee walls to the crawl space under the eave.. If there is a sloped transition between the ceiling and knee walls in the finished 2nd floor, you will also need to get insulation down this slope (which is really hard).

You have to create a continuous envelope separating the heated area from the outside.

That stuff under the vinyl siding is NOT insulation. It is properly called "leveling board".

SVreX wrote: Soffit= overhang. If it is a porch ceiling, etc. that is not over a heated area, it does not need insulating. If it is a cavity over a heated area, you need to cut the roof sheathing open high enough to get in there to work. All of the heated areas need to be separated from the outside by insulation. So, the walk in area needs to be insulated at the floor, or alternately the roofline. The ceiling over the 2nd floor and the "proper" attic needs to be insulated, and so do the walls from this room to both the wall in area and the knee walls to the crawl space under the eave.. If there is a sloped transition between the ceiling and knee walls in the finished 2nd floor, you will also need to get insulation down this slope (which is really hard). You have to create a continuous envelope separating the heated area from the outside. That stuff under the vinyl siding is NOT insulation. It is properly called "leveling board".

That's why I asked. I'm new to this stuff.

Should I be using a vapor barrier with the new insulation?

Ideally, there should be a vapor barrier on the warm side of the insulation, but that can be problematic to install without tearing out all the ceilings in the house. The most important thing is to block all air infiltration into the attic from the house - seal up around vent stacks, wiring, or any other places you can find.

Also, there should be air flow from the soffit area up into the attic, on the cold side of the insulation. This assumes there are vents in the soffits for fresh air to come in, and vents in the roof to let air pass on out.

Blown in cellulose or fiberglass is probably the most economical choice. Spray in foam would be better, and would also seal air infiltration and provide a vapor barrier, but it's generally a lot more expensive.

edit: if you're going to use a pellet stove in the living room, is it going to have a fresh air intake for combustion air? If not, it's going to be pulling air from the room (and that air has to come in through air leaks.) Also, that combustion will create carbon monoxide, so be careful about that - if nothing else get a CO detector.

With hard-to-access places like that, you might want to look into spray foam insulation like this stuff. You get insulation and a vapor barrier all in one. (I also just learned that it can increase structural integrity too, in some applications.) (Applications, get it?)

There's also that 'blow in' stuff. It's not as efficient as true batt type insulation, but in difficult to reach areas it beats the heck out of nothing.

Something else about soffits: they also allow air to flow upward to the vents, removing moist air from the attic. So you don't want to block them.

When insulating the walls, it's going to be a royal pain in the azz no matter which way you go. The leveling board SVReX mentioned helps, but its insulation value is practically nil. The choces are (in order from most to least efficient):

1) Remove the inside plaster or drywall, install batt insulation, a vapor barrier and then recover with drywall. Doing it from inside is best because you can add a continuous vapor barrier which cuts down on air infiltration.

2) Remove the outside siding and install batt insulation from the outside, this does install a vapor barrier but it's in pieces, there can be gaps at the edges of the studs which will allow cold air infiltration.

or 3) 'blow in' insulation through holes cut in the walls. The 'blow in' is least efficient because it has voids etc and does not add any sort of vapor barrier but it beats the heck out of nothing. It's also the easiest, although it still requires a fair amount of drywall or plaster repair or if done from the outside siding repair. Cellulose: http://www.builditsolar.com/Projects/Conservation/WallCellulose.htm

Foam: http://www.fomofoam.com/existing_homes.htm

Don't forget the floors. It's no big deal around here, but in really cold areas a lot of heat can escape through the floors. That's not fun, the only real way to do it is with batts from the underside, same way you'd do the walls from the outside. When you do this, you will need to insulate the pipes. Since heat escaping through the floors would keep them from freezing, if you remove that heat source you need to protect the plumbing.

Definitely get a home energy inspection through CL&P. It's $75, and what you get out of it is definitely worth many times that. An independent company will come in, perform the energy audit, and then remediate your biggest issues (all included in the $75). They're paid based on the % improvement before/after, so the incentives are in the right place.

If you're in Fairfield County, I can recommend a great vendor that we worked with - Greenstar Energy Solutions - http://www.gogreenstar.com

They took the time to explain everything, and even told us that going with a heat pump with another vendor was a better move than getting the blown-in insulation with them. In addition to the service, when we did it a few years back, there were extra incentives on top of what was publically available as part of the energy audit.

Feel free to send me a PM if you want any additional info, and I can walk you through the process...

I really like the home energy audit idea.

You have a difficult house to insulate, and it's pretty hard to know all the details from internet pics, and to describe what is needed effectively with your limited construction background (may not know the technical verbage, etc). An inspector can lay eyes on it, walk you through it, and give you sound advice which will enable you to proceed.

We can give you advice, but honestly you are gonna miss something big.

That is a good tip. I didn't know CL-P sponsored something like that. I'm making a call in the morning. I'll let you guys know what the findings are.

http://www.cl-p.com/home/saveenergy/rebates/homeenergysolutions.aspx

go to a Home Depot rental and get their AttiCat. Its a blow-in insulation machine with a remote control built into the hose. If you buy 10 bags or more of the insulation, the rental is free.

You want fiberglass in the ceiling/roof and cellulose in the walls. You can also rent the Green Machine for free if you buy 20+ bags of cellulose.

Fiberglass is a better insulator (by a very small margin) but it doesn't "flow" well which is why you use it to fill large areas. Cellulose works well in walls because you can break it up into smaller pieces and they don't "clump."

In that attic, I would use batted rolls in those rafter spaces against the roof, then cover them with at least plastic if not ply/drywall. Then rent the AttiCat to fill the tougher spaces. If your walls aren't insulated, drill 2" holes between each stud and use the Green Machine with cellulose.

A little trick (since I work for Home Depot Rental)... buy the required amount of insulation to get the free rental, and you can return any unopened bags later. The total investment will probably pay for itself in three years... sooner if you live in an area that also has high A/C costs.

I've walked about 300 customers through this exact process. PM me if you need to know more.

The non-GRM way is to hire someone to do the spray foam insulation. It is superior in many ways including draft resistance, R-value, and resale value, but its not cheap.

The other thing we did at our old house was we basically had interior storms made. We went to a plastics company in Bridgeport with the window measurements, they have us the clear sheets of plastic and the material for the frames, and then you made your own frames. It was much cheaper than buying all new windows for that house, and it made a large difference during the winter. We also had two sliding glass doors that we covered up in plastic for the winter. Along with insulated curtains, that made a big difference in our dining room (which had sliders on both exterior walls).

One of the interesting things from the energy audit was that new windows are one of the worst bang-for-the-buck changes to reduce heating costs. The guy said that caulking around the trim and eliminating gaps would be far more cost effective.

Searching info related to this thread, I found this guy's site. May be helpful- I'm planning on his cheap spray in foam solution. Great idea for my basement. Take a while, but probably a lot cheaper than actual spray in foam.

http://www.howtohomeinsulation.com/

In reply to curtis73:

Home Depot has taught you well.

Cellulose can clump, and it can also settle. A lot. I've seen walls opened up where the insulation had settled leaving 1/3 of the cavity empty at the top. It is a very good choice for spraying into walls, but there are techniques to doing it properly which are not taught by reading the instructions on the bag.

Also, there is a lot of evidence that exposure to air borne fiberglass fibers may be a carcinogen. Proper training and personal protection equipment is a MUST.

Fiberglass is NOT a better insulator than cellulose. Fiberglass is susceptible to changes in temperature, and the glass fibers at times can transfer heat/ cold (just like your windows). Temperature can reduce the effectiveness of fiberglass by large percentages. It is used in sprayed applications such as attics primarily because it will spray further out of the spray nozzle, which reduces the labor. It is also easier for installer to cheat people using fiberglass because it "fluffs" more, so it looks like there is more product.

Air infiltration is by far your biggest enemy. Cellulose (when installed properly) can seal better. Sometimes.

It may be non-GRM, but there are other considerations to a good insulation job.

Whether or not you intend to DIY, an energy audit would be a good investment.

Insulation basically works by trapping air so it doesn't move (yeah I know it's really more complicated than that, but let's keep it simple). So the idea is to keep the percentage of fibers or whatever down yet not allow air to move, since the moving air is what carries heat to or away from something.

Fiberglass batts with a vapor barrier are pretty much the best of the reasonably priced technologies available. The cellulose stuff is good from an R value standpoint (and much better than an empty wall cavity) but as SVreX noted it can settle. That creates two problems: an open space where air can move and a tightly packed material which can transfer heat. Still better than nothing.

Spray type cellulose is becoming more widespread in new construction but for a retrofit has the same disadvantages as fiberglass batts: the interior walls need to come down, the cellulose sprayed then allowed to dry, trimmed, then a vapor barrier and drywall are put over it.

From a DIY and dollars standpoint, the blown in cellulose is probably your best bet. The slow expanding foam might be worth looking into but will be a good deal more expensive.

Did the foam years ago in my 1870's house. I very much regret it. Would not do it again, would never recomend having it done.

foxtrapper wrote: Did the foam years ago in my 1870's house. I very much regret it. Would not do it again, would never recomend having it done.

Why so?

Curmudgeon wrote: Insulation basically works by trapping air so it doesn't move (yeah I know it's really more complicated than that, but let's keep it simple). So the idea is to keep the percentage of fibers or whatever down yet not allow air to move, since the moving air is what carries heat to or away from something. Fiberglass batts with a vapor barrier are pretty much the best of the reasonably priced technologies available. The cellulose stuff is good from an R value standpoint (and much better than an empty wall cavity) but as SVreX noted it can settle. That creates two problems: an open space where air can move and a tightly packed material which can transfer heat. Still better than nothing. Spray type cellulose is becoming more widespread in new construction but for a retrofit has the same disadvantages as fiberglass batts: the interior walls need to come down, the cellulose sprayed then allowed to dry, trimmed, then a vapor barrier and drywall are put over it. From a DIY and dollars standpoint, the blown in cellulose is probably your best bet. The slow expanding foam might be worth looking into but will be a good deal more expensive.

That's wet spray cellulose.

Dry spray cellulose is suitable for retrofits.

Right, but as I understand it the wet spray is designed to 'stick together' and is not so prone to settling.

stuart in mn wrote:

foxtrapper wrote: Did the foam years ago in my 1870's house. I very much regret it. Would not do it again, would never recomend having it done.

Why so?

It's solid. This means you really cannot ever run another line through that wall again. Quite frustrating when trying to upgrade wiring. While it's soft, shoving 10' of wire through it will generally defeat you. Plus you're tearing it all up.

The stuff shrinks. This means while trying to run a wire through it you can successfully tear a big hunk off a wall, where it will now rattle in the wind. That section of the wall with the rattling foam board has also lost almost all of it's insulated properties.

The guys that blow it in shove the hose up to the top, start squirting, and pull the hose down and out. They miss a lot of spots doing this.

If you've a balloon frame construction, the foam sags into the floor spaces, and out of the walls, as it sets up.

As they blow the foam in, it squirts out the various holes in the wall. From electrical outlets to pipe holes in the cabinets.

The installers drill upwards of a hundred 2" holes all over the outside of your hose to blow the foam in through. They patch them by hammering in tapered plugs which swell from contacting the damp foam, split your siding, then fall out.

Curmudgeon wrote: Right, but as I understand it the wet spray is designed to 'stick together' and is not so prone to settling.

That's correct.