More insulation or more BTU's?

[stefanc]

Since I moved in this house 5 weeks ago I've changed all the bulbs to CFLs, added the insulation to the attic and installed an insulated pre-hung garage entry door (replaced a door with 1/2" gap below it and 2" gap above hidden by trim!) So I am making some progress, just not as much as I would like.

[Xringer]

803 / 30 =26.766 /24 =1.115 kw (3804.538 BTUh) per hour. On average.

If you double that?? 2.23 kw ~ 7609 BTUh needed every hour 24/7.

So if you had an older Sanyo ASHP like mine, with a COP of 3.41 (Coefficient of Performance),
would get you about 26,000 BTUh of heat.. (using 2.23 kw)..
On an average day, I think my system will use 600-700 watts to make 7609 BTUh..


http://i46.photobucket.com/albums/f1...L/poweruse.jpg

I'll bet some of those fancy new models will do a bit better..

Even if you installed a small 12,000 BTUh inverter mini-split, you would likely cut your bill by a very noticeable amount..

[AC_Hacker]

Originally Posted by stefanc

So I am making some progress, just not as much as I would like.

There has been some very interesting discussions in the Forum regarding actual blower door testing, Daox's bathroom and kitchen extractor testing, I think he might have called it poor-mans blower door or something.

One of the more compelling contributions to this discussion, in my opinion, was from S-F, who recommended positively pressurizing the house, and using smoke sticks to determine the source of leakage. S-F's observation was that the escape of air will very dramatically bend the smoke into the leak, eliminating any doubt exactly where the leak actually is.

So if you can come up with some kind of husky blower, and positively pressurize your place, so much the better.

Which all got me thinking about a high-volume window blower I hacked together for use in extracting air particulates from rooms where lath & plaster is being demolished.

So this high-volume blower was scrounged from a low-efficiency furnace that my friend, Bruce-the-pirate was about to haul off to the dump. I cut a piece of plywood so that it would fit into one of my windows pretty well. Then I cut a rectangular hole in the plywood, and bolted the blower fan to the plywood. It works plenty good as a particulate extractor, and I think it will supply all the positive pressure I need to do the testing.

So you may not actually need to do the blower door test with so much glorious junk laying about, you can do a Blower Window Test!

-AC_Hacker

[GaryGary]

Hi,
You can get a rough idea what upgrading insulation in a particular area will save you with this calculator:
Cost Saving for Insulation Upgrades

And/or you can do a simple heat loss for the whole house with this one, and it will give you an idea of where most of the loss is (that is the loss through walls, through ceiling, ...).
Home Heat Loss Calculator

The HSPF 8.2 translates to a COP 2.4, which is basically an efficiency of 240% compared to the about 100% you get with your resistance heat, so, if it actually works as promised it should at least cut the space heating part of your electric bill more than in half.

Have you checked on whether your utility offers an energy audit program? Usually these include a blower door test, which would give you an idea how leaky the house is.

There are lots of things you can do with windows to reduce heat loss -- even double glazed windows are a pretty big heat hole.

Gary

[S-F]

I deal with this exact issue every day. While your resistance heat is probably the most expansive option available it will cost a pretty penny to install minisplits. The units with multiple heads are less efficient as well. Due to (probably?) marketing, the desire for new things and our innate fascination with gadgets the first thing people think about when energy efficiency crosses their minds are new windows and heating systems. The catch is that these are the most expensive options with the longest ROI; i.e. probably not in your lifetime. The most cost effective solutions are usually not even considered and are often not offered by contractors. Air sealing and blow in cellulose. I've been working on a house for about a week now. I have done some insulating but mostly air sealing. Every morning when I get there the young couple tells me that their house was more comfortable than it was the night before and their boiler is coming on less. This is very moving for me as they seem like nice people, clearly don't have a lot of money and they appear to deeply love their young daughter who is disabled. The simple fact hat their bedrooms are more comfortable during the cold nights is evidence enough for me. Sure they could have spent the $7 K on replacing their oil burner with something fancier, but the house would still be hot in the summer and cold in the winter. I haven't even used the blower door for leak testing. I just took a measurement when I started. The pressurized testing will one of the last things I do. So my advice is to meticulously air seal, get cellulose in the walls if you don't already have it and build window inserts like Daox and Xringer.

About spray foam for air sealing, don't get a two part kit. That's only for certain situations. Get a one part gun and some good cans of foam. Get a case of it. Use caulk for interior gaps and cracks and fire caulk for next to hot things.

[Ryland]

I agree, expanding foam doesn't need to cover the whole area, it just needs to fill the gap that has a draft, your house is like a chimney, cold air enters the lower parts, gets warmed and exits out the top, so you will see the largest reduction in drafts if you go in your basement or crawl space and seal up cracks where the wood sits on the foundation and around any pipes that come in to the house.
Then do the same thing in the attic, seal up any cracks where walls meet the ceiling, holes where wires go in to the top plate of the wall, around drain vents, if you have fiberglass insulation in your attic you will most likely find dirt and dust caught in the fiberglass near these holes.

[Xringer]

"build window inserts"..
That's good advice. And, if you can get the frames that can take
Spline on both sides, or attach two regular screen frames back-to-back,
I think it's going to work amazingly well..

http://www.advancedenergypanels.com/...mghow-c2r3.jpg
http://www.arttec.net/SustainableLiv...EP_diagram.jpg
http://ecorenovator.org/forum/conser...or-storms.html

Mine only have the single sheet of plastic covering our Andersen Thermopane sliders, (64 sq feet),
I'm very impressed with the way they are working so far.
(However, they are being helped by the new curtains we installed this year).

The heat loss in the den is way down from what it was.
Plus, the foam on the edges of the frames do a good job of blocking the little air leaks in the sliders..

That old Sanyo in the Den isn't going to be working near as hard this winter..
Unlike the past few decades, we will be using the den in Dec & Jan!

[creeky]

I'm with S-F on this one. Sealing up the cracks and holes will give you the biggest bang for the buck. When we replaced our windows I found that they had been "sealed" with compressed fiberglass insulation. I could have done myself a lot of good by removing the trim, pulling out the insulation and foaming the windows ...

However, we too were on electric baseboards and we cut our bills by sealing all the windows with plastic. It's cheap and takes an afternoon. Our sliding glass doors from the family room got two layers. One inside and one outside the house. This is because the first wind storm from the north west pushed the inside layer into a balloon like shape and eventually broke the seal.

I added a pellet stove in the basement. That sucker saved us thousands of dollars. We had a wood stove but it was so messy. The pellet stove was cleaner and more manageable for us.

I also spray foamed and put gaskets around switches and plugs on the exterior walls. I also put new gaskets around all the doors.

Had I known about sill plate insulation I would have done that too. But I hadn't joined this site yet. There's a really good post on sill plate insulation. Maybe somebody else remembers who did it. Good luck.

[stefanc]

Thanks for pointing me in the right direction here guys.

It was very windy here the other day and my wife noticed the windows were pretty drafty so building window inserts are high on my list. I'll also insulate all exterior switches and outlets, and dig around the attic to see of I can do some more sealing up in there.

My utility company will credit me towards the cost of an energy audit. Not sure if this includes a blower door test- if not I'll probably build a blower and do the test myself after the storms and additional sealing is done.

I'm seeing alot of fallen hardwood trees for free on craigslist, and I found a great soapstone lined woodstove that's sized about right for my house. I'm leaning towards wood for primary heating. I usually have some time off of work at random times so I can spend it splitting wood .

The mini-splits will probably be ordered in the spring, sized for the cooling load. I think one unit for first floor and one for the second floor. The would probably only be used for heating during fall and spring when it's not feasable to fire up the stove.

During the winter I'm also going to be keeping an eye (and pictures) on the sun to see how well a solar DHW heater will work.


So that's my list for now, let me know what you guys think.

Thanks!

[Xringer]

I assume your 3-season room is not going to be used much during the winter.
Take a look at your Pella Rear slider. See if you have a flat surface where
plastic film can be attached with tape or double sided sticky tape.

I've looked at my slider in our Den, which faces north,
and it looks like I can install a film, that will have about 1/4" of air gap over the glass.

That's about 33.6 square feet of glass(and aluminum frame).
When you stand next to it, you feel it.


Even if I only add a layer of plastic to the left side, I'll bet the savings
in BTUh will pay for the cost of the plastic within a few weeks..