Energy efficiency and the like

[PeterB]

I was just reading a news item about GWB's State of the Union address. It quoted him as saying the USA has to get over its addiction to oil.

Reading this reminded me of some comments my brother made after his experience of living in Kansas City for a year.

I get the impression that many American homes aren't insulated, and people rely on various forms of heating to stay warm in winter. Is this so?

Where I live (Canberra, Australia), houses are rated for energy efficiency on a six point scale. My old unit was rated at 5.5 out of 6, because it was double brick and built on a concrete slab.

By contrast, the house my wife and I bought is rated at 1.5 out of 6. When purchasing the house, we saw the energy efficiency report on the house, and the suggestions it made for increasing the EE rating - underfloor insulation, heavy curtains and pelmets, double glazing on windows, draft-stopping strips on doors, and a few other things. After getting our winter electricity bill, we're investigating all of these options, because we see the cost of installing these things as money-saving investments, and a simple way of improving the resale value of the house in the future.

Also, all new homes must include enough energy saving devices that they rate 4 out of 6.

Are there programs like this anywhere in the USA?

[Bob B.]

peterb said:

I get the impression that many American homes aren't insulated, and people rely on various forms of heating to stay warm in winter. Is this so?

American homes are most definitely insulated. I don't know what the building codes are, but from what I've seen, the walls of most homes are insulated with 4" of fiberglass batt insulation. The roof is even more heavily insulated -- I'd guess at least 6" of fiberglass or an equivalent amount of blown-in insulation.

EDIT:

After reading echnaton's post I thought is necessary to point out that I live in Ohio where we have a pretty wide range in temperatures. 0^o F in the winter to 90^o F in the summer is not unusually, and we sometimes exceed those temperatures. My comments about insulation are typical for this part of the country. I don't know what the norm is elsewhere.

[echnaton]

One of the problems with ratings systems is that different climates need different types of insulation systems. In Houston, we are hot and humid and our systems need to allow moisture to move through the walls and out of the structure. The temperature difference between the inside and outside is rarely greater than 25 degrees F but we sometimes run the AC in January just to remove humidity (and occasionally to cool). In dry Arizona, systems can be more airtight because moisture retention in the living area is preferred. In the northern climates they have to bulk up on insulation because of the large spread between the indoor and outdoor winter temperatures.

We just went through a renovation on our house and the contractor had to meet the insulation building codes for the City of Houston and receive a permit before he could close the walls. Most of the uninsulated houses in the US are older structures build before fiberglass was in use. Sometimes it is not worth the cost to open the walls to fully insulate them and there is no requirement to do so when selling. In fact in the Gulf of Mexico coastal areas, the moisture retention properties of some insulation materials, like cellulose, can shorten the life of a structure.

[bughead]

Different areas have different insulating needs, but different times have resulted in different solutions even in one area.

My house was built in '51. The walls have some fiberglass in them, but the attic was only insulated in '74 or so by the next owner. He blew in "cellulose" which is a fancy word for lint.

Also, I've read that houses built before the 1980's have the equivilant leakage of a 2'x2' window open all year round. Now builders use tyvek and sheetfoam insulation, butyl tape on window flanges and all kinds of things to control the air-exchange between inside and outside.

A technique I've read about and have started implimenting as I gradually rework my attic is ventelating the roof. When we had the shingles done we had corrugated plastic ridge vent installed. I'm using polystyrene foam channels (stuff like the old plastic egg cartons were made of) to carry air from the soffits up under the roof decking to vent out the ridge. It gets batts of fiberglass stapled over when done. In the end the roof stays cold, the attic stays cool, the house stays a bit warmer. The attic floor and lint are another project altogether.

Modern building codes vary by area but insulating walls with R13 between the studs and R30 in the roof trusses is what I've seen. I've read trade magazine articles about using TGI 2x12 rafters for big vaulted ceilings. In part this is done to "superinsulate" the room to R52 or something.

Insulation is cumulative, by the way. If you ever have a chance to add a layer when redoing a room or something the payback is less than 5 years of current natural gas prices before the insulation pays itself off. Even stuffing new fiberglass in place of old when remodeling is good.

[bughead]

and another thing:

My parents put storm windows on the house back in the 80's. The way the tax writeoff went, they deducted some fixed large number from the first year's taxes and some amount for subsequent years until the cost of the windows had been effectively repaid by the goverment.

Ronald Reagan (p'tooie!)(makes sign of evil eye) discontinued this tax savings, as well as a solar energy tax credit also in place.

[Bob B.]

bughead said:

Modern building codes vary by area but insulating walls with R13 between the studs and R30 in the roof trusses is what I've seen.

The R13 rating is the 4" fiberglass batt insulation I mentioned in my previous post. R30 is equivalent to 10 inches of fiberglass, which sounds a lot better than my guess of 6" (R19).

[petereldergill]

American homes are most definitely insulated.

If it's anything like up here in Canada, not all homes are insulated. My home in Toronto has a double brick wall with no insulation in the walls or basement. The attic has minimal insulation.

That being said, I have spent lots of money insulating. 12" of blown in insulation in the attic and a company came to pour sprayfoam into my wall cavity (only about 1", unfortunately). This eliminates drafts, which causes tons o' heat loss. I am also currently insulating my basement walls as well (R13)

If anyone has more questions, please check out
www.mikeholmesfanforum.com or
www.joneakes.com

There's tons o' info at those websites about home renos

L8R

Pete

[Bob B.]

petereldergill said:

American homes are most definitely insulated.

If it's anything like up here in Canada, not all homes are insulated.

I sure there are probably some homes that are not insulated, but I'd guess it's a pretty small percentage. The original comment was, "many American homes aren't insulated". This could be true because even a small percentage amounts to many in a country this big. However, if the meaning of "many" is "a significant percentage", then I would say this is false.

[petereldergill]

Maybe I should rephrase. Here in Toronto (and other cities where it's much colder), pretty much any home built before 1960 is of similar construction to mine. Extremely well built, but no insulation in the walls. My home is pretty airtight, but homes built before 1940 are drafty and no insulation.

You'll find homes even in Winnipeg (or Winterpeg as some call it) with little insulation

Of course, all new construction must be built to code, which means decent insulation.

It seems that energy was pretty well "free" back in the '50s and before, or at least much cheaper than it is now.

I wouldn't hazard a guess as to the percentage of homes without proper insulation...unless you want me to make something up!

Just FYI, my gas bill for heating and hot water is about $1300 per year for a 1250 sq ft bungalow with full basement. Hopefully that goes down alot since I've got the work done, but it's been a super mild winter in Toronto this year...

TTFN

Pete

[petereldergill]

Insulation is cumulative, by the way. If you ever have a chance to add a layer when redoing a room or something the payback is less than 5 years of current natural gas prices before the insulation pays itself off. Even stuffing new fiberglass in place of old when remodeling is good.

It is cumulative, but not linear. You must double the R value to halve the heat loss.

Going from R10 to R20 would cut the heat loss by 50% of the current value. But then to cut it in half again, you'd have to get to R40. It's the same as half life for radioactive elements, I believe.

There is a great American source of info caled buildingscience.com I think, which should have the info.

L8R

Pete