Help me with a crowd-sourced energy audit

I am closing on a mostly flat 5 acre parcel in a few weeks. The house, has adequate attic insulation already in place, and storm windows which are tight and operable. It has good southern exposure, but the layout is not well designed to make use of this. It was owned by a carpenter who took care of things well, until he died suddenly over the summer while pulling a stump out. Sad, but at age 87, not a bad way to go.

My biggest concern is the energy hog heating system. They did have a wood-burning furnace, but the Mrs. got tired of it and convinced her husband to get a gas furnace in 1978, which runs on very-expensive propane. She estimated her propane bill to be $2900 this past year.

I am considering hiring a home energy audit company to come out, but I suspect they'll just tell me to get a new high-efficiency gas furnace. I'd like to consider other energy sources as well. That is where you come in.

I am willing to invest $15k-$20k in making the house as energy efficient as possible, but would like it to pay off in 10-15 years. What do you think is the best way to accomplish this? I am open to any and all conventional and renewable energy source options.

Thank you all greatly!

What region of the world are you in?

This would inform the energy / heating source recommendations.

Northern Illinois

was in the biz for 25 years
Check with your utility, they may do an audit for cheep or free. (blower door and infrared)

Make sure exterior walls are insulated

In the attic, look to see where anything comes through the ceiling. If there is a gap around them (if its a flue (hot) seal with flashing and high temp caulk at ceiling level). If it is a plumbing vent (cold) seal with foam or caulk, insulation board if the gap is large.

Check the top plates of walls, especially plumbing walls or walls with cabinets. Seal them at ceiling level with insulation board and foam if they are open. Cold air will fall through the insulation into interior walls and make them cold. These are "thermal bypasses".

where are the ducts and what type of foundation?

Do you want to go back to wood?

Do you want air conditioning?

Congratulations on your new place!

What shape is your roof? An old farmhouse probably has a good slope to it. Does it have a largish continuous area that faces more or less south? If so, you have a good location for either photovoltaic or hot water collectors. In New York State there are currently incentive programs and some regional initiatives to make solar investment easy... check your state for any useful programs. Also see if any utilities will do the solar installation/leaseback plan that lets you take the payments out of your monthly utility bill.

Payback is important to many. A professional may want to tweak this list. Here's my list of energy savings from fastest payback down.

1. Turn down the thermostat.

2. Air sealing of windows and doors, around electrical stuff and all of the attic stuff listed earlier.

3. If continuing to use the old system for a while, have it serviced.

4. Attic insulation.

5. Floor insulation.

6. Wall insulation.

7. New windows. This could save a lot of heat, but it is expensive and can have a long payback. Installing the storm windows stored in the garage will give you an immediate return.

Po White : All houses breath, a house can be too tight, but it will take a lot of work to even come close on an older home !

Your house will breath out at the top of the house exhaling warm moist air (especially if your houses roof is vented ! )
As this warm moist air infiltrates through your attics insulation it will meet a temperature band that will cause water vapor
to condense and collect and settle out, this will show up 1st as little frost-icicles on nail ends poking down into your attic
space, as your winter gets colder this frost line will desend lower and lower down into your insulation !

This will happen even with a vapor barrier due to rips, punctures, and unsealed penetrations of electrical and drain waste
vent pipe ! This effectively reduces the amount of insulation that is actually working for you !

As you are losing both more and more heat, and the effectiveness of your insulation, cold air is being drawn into the house
from around your foundations sills/floor joists, and cellar windows doors and electrical and water penetrations !

To understand more about how your house breaths -Google Stack Effect, and Whole house Stack Effect !

On top of your foundation you have a wooden sill plate which may only be a 2 x 8 or it may be an actual Beam !
The 2 Xs of your floor joists set on the sill plate and meet the end plate at the outside wall. This creates a box section
between every two floor joists and the floor above, open at the bottom.

Old code mandated that these spaces right there at the outside wall be insulated, and the code even allowed for loose fill,
fiberglass, or rock wool in these spaces ! Again moist air from the basement and crawl spaces, or drawn in at the floor
joists and end plate will condense and with 70 % trapped humidity grow molds, and at 90% humidity grow Rot !

This condition is believed to exist in about 30 million houses in the U.S. and Canada !

Current code requires this type of insulation be stripped out of these box ends and a rigid non-porous foam board be
cut to fit each individual cavity, and then the foam board(s) are spray foamed into place !

Any mold found will in the future absence of high moisture levels simply lie dormant, many people use a paint brush
to paint on a diluted mix of bleach to water, read the label !

Grasping how your house breaths, and where moisture problems can occur Will help you save on your future energy
costs !

Big AL