Dual-pane windows were invented in 1935 but weren’t widely used in the United States until the 1950s. Our windows were manufactured by Andersen and they are true divided-light single-pane casement windows. When the house was built, fuel oil was inexpensive, so it was more cost-effective to simply burn more oil than it was to invest in insulation and very costly dual-pane windows – not when you consider that our house has 40 windows incorporating a whopping 136 separate window sashes!!

A single-pane window has an R-value of 0.91. Dual-pane windows usually have R-values starting at 2.0, and super-efficient triple-pane windows can achieve R-values greater than 3. But there’s more to windows than just numbers.

There are three methods of heat transfer: radiation, conduction, and convection. Radiation is the heat you feel from the sun; it warms objects. Conduction is heat that passes through materials; nature will always try to balance the heat on both sides of a barrier.

The last method is most important when considering windows: Convection. When the warm air in a room hits the cold window glass, it loses heat. The now-cold air sinks down, pulling more warm air in behind it. This creates what is called a Convection Current, and it creates drafts that can make a room much less comfortable.

With heating oil hovering at the $4 mark, we started looking for ways to reduce the drafts in our old windows. One of the methods we tried last winter was to cover the window screen inserts with insulating window film; the kind you attach with double-sided tape and shrink to fit with a hair dryer.

These worked, sort of. The main problem was that the air gap they created was nearly 2 inches wide – plenty of space for a convection current to be created in the gap. So we were still losing heat; it was now just a two-step process. They tended to wrinkle, and were prone to tearing. Also, covering the screens meant we couldn’t open the windows for ventilation.

A few months ago Bob started researching other options. He had decided that plexiglass inserts were going to give us the best results, but the issue was finding a supplier that could both cut to very precise tolerances (to the nearest 1/32^nd inch), and at a price that wouldn’t require a second mortgage. He finally chose TAP Plastics.

So we started measuring the windows. A regular measuring tape simply wasn’t going to be accurate enough, as we had to be as precise as possible so we could get the tightest fit. Bob found this ruler at the hardware store and it was the perfect tool for measuring inside dimensions.

This is a Lufkin X46 Extending Ruler. It has a brass extension bar that lets you get amazingly precise inside readings. To make sure we got the most accurate measurements, we each took them independently and then compared numbers. If we didn’t get the same numbers, we went back and re-measured. A lot of work, but the end result would be worth it.

We then ordered the plexiglass. For most of the panes, we chose 1/8” thick clear plexi, so there would be less chance of wobbling or warping. For the smaller panes (the ones in the French doors, which we would have to do individually), we chose 3/32” plexi.

Installation

Each piece of plexiglass was protected by two sheets of blue adhesive plastic. To get started, Bob would peel the plastic off one side of the plastic, and then set it in place in the sash, right up against the muntins. This would leave a gap of between 5/8” and ¾” – just right to create a true dead air gap.

While pressing the plexi against the window, Bob started to peel back the front protective plastic. To hold the plexi in place, he used these little things:

They’re called glazier’s points, and they’re meant to hold panes of glass in window sashes. They’re usually covered up by the window putty. In our case, we were going to use them to hold the plexi tightly against the sash. They are just pushed into the wood frame with a flat tool, like a paint scraper. Each sash required about a dozen points.

Once the plexiglass is installed, it is hardly noticeable:

So, did it work?

We’ll let the pictures tell the story.

This is a three-sash window on a north-facing wall. The left sash is the plain single-pane window glass. The center sash has the screen insert with the window film applied to it. The sash on the right has the plexiglass installed in both the lower and upper sashes. It’s a huge difference!

Here’s another example.

This is a French door on the opposite wall of the same room. Only one pane has the plexiglass on it. Can you guess which one?

We now have this plexiglass insert in every single-pane window in the house. The total cost for the plexiglass was about $1800, plus another $40 for many packages of glazier’s points (we’ve managed to clear out the stock in all three area hardware stores). Applying the plexi took about five minutes per sash; it took more time to wash each window thoroughly before the application!

Would you believe… neither?

Calculating the cost savings for replacing either an HVAC unit or windows can be tricky, but it’s worth doing the math to make sure you’re spending your improvement dollars wisely.

Keeping your cool

Let’s take the example of an older gas furnace/AC unit. If the average summer electric bill is $300 and the average winter bill is $175, then the AC component of the electric bill is around $125 per month. Older units can have efficiency ratings of around 8, and new ones are rated at 16, so in theory, you could cut the AC component of the electric bill in half. But how much are you saving, really?

In the DC area, air conditioning is used for three to four months of the year. Even if you upgrade to a unit with double the efficiency of the old unit, your total savings could be surprisingly small:

Old unit: $125 x 4 months = $500 electricity cost for AC

New unit: $75 x 4 months = $250 electricity cost for AC

So the new unit will save you $250 per year. Assuming you spend $6000 on the new unit, the payback period could be as long as 24 years… much longer than the expected lifespan of the new equipment. If your existing equipment is still working, a more cost-effective option is regular maintenance. Have it tuned, change the filters regularly, and make sure all ductwork is sealed properly.

Uninsulated ductwork in attics leads to excessive energy loss and increased utility bills.

What about windows?

Window efficiency is expressed as “R value.” An old single-pane window has an R value of one; if it has a storm window, it goes up to two. A new modern double- or triple-pane insulated window can have an R value between 3 and 6. Replacement windows start at around $250 per standard opening (and that would be for vinyl single hung inserts with an R value of 3), and an average house has about 12 windows, replacing them all can easily exceed $3000. Full replacement with wood-framed windows can easily be triple that. That’s a lot of electricity cost to recoup.

Simply closing the latch on this double-hung window will help lower energy bills.

Before choosing to replace windows, make sure the gaps around the frames are well-caulked. Fix any loose latches or hardware so the windows close tightly. Add operable draperies to cut down on heat gain/loss.

One upgrade that makes sense

An item that is often overlooked as an energy hog is the refrigerator. A fridge that is only 5 years old may be using twice as much energy as a newer model, and fridges use much more energy than people think. After all, they are running all the time! Many houses also have a second fridge in the basement, often containing just a few items. These smaller secondary fridges are usually bigger energy hogs than the one in the kitchen. Replacing an inefficient fridge with a new Energy Star rated model could pay for itself in energy savings within five years.

The broken icemaker and stains on the gasket indicate this fridge might be a candidate for replacement.

You can check whether it makes sense to replace your own fridge by using the government’s Energy Star Calculator.

Water

This gutter is obviously not helping direct water away from the house.

A large percentage of home problems are related to water going where it shouldn’t. Start outside, looking at the house. What does the roof look like, and how old is it? What do the gutters, downspouts and splash blocks look like and where does the water go when it reaches the ground?  Any erosion, moss, stains or other ‘clues’ evident?
Once inside, check for stains on ceilings or walls on the top floor (possible signs of a leaky roof).  Are there any stains or patches underneath bathrooms on the other floors? What does it look like underneath the sinks? When you go into the basement, are there any odors, dampness, rust stains or discolored cardboard boxes on the floor? Does the furnace have any rust stains?

Gas

Evidence of a previous gas fire. Amazingly, a prior Inspector failed to spot this during his inspection.

Gas is easy: everything should work and there should be NO ODOR!  If you smell gas
when walking into a home, walk right back out. You might get a brief whiff if you are standing next to a stove or fireplace as it starts to light, but NEVER when first entering a home or even a room.  If you smell gas and you are not standing close to the appliance, there is a dangerous problem. Leave the house immediately and call 911.

Electricity

An outlet with scorch marks can be a red flag for potential electrical system issues.

Repeat after me: “Extension cords, wire nuts and black tape are generally BAD” A $7 electrical outlet tester will tell you a LOT. Is the outlet working? Is it loose in the wall? Does it hold an inserted plug firmly? Has it been painted over? Do all the right lights light up?
Older houses may have a mix of two-wire (ungrounded) and three-wire (grounded) outlets. If it seems like there is a random distribution of grounded and ungrounded outlets, the grounded outlets may not actually be grounded to anything, which constitutes a safety hazard.
A quick look at the electrical panels may also tell some stories.  Fuses are not necessarily a red flag; they are just old and obsolete, and you could be looking at (expensive) upgrades to bring them up to current standards. Rusted panels, or Federal Pacific, Zinsco and Bulldog Pushmatic panels all need to be replaced as they are documented safety hazards, and this is an expensive repair. Messy wiring with lots of loose wires everywhere probably needs some TLC from an electrician.

Heating and Cooling

This furnace had not been maintained and was crusted with layers of dust and corrosion.

It should be working and be REASONABLY current. System efficiencies have gone up a LOT in the last few years, so a 17 year old system will cost you extra each month until you replace it.  Any system more than 17 years old is a candidate for replacement; between 10 and 17 years old and you might want to consider upgrading if you’re planning on staying in the house for five or more years. A system between five and 10 years old just needs to be maintained, and anything under five years old is nice to see.
HOWEVER!!!  If the fuel bills are reasonable, then replacing a SAFE and WORKING 20 year old furnace with a new $9,000 one doesn’t make sense as the payback is probably longer than you will be in the house. Then again, I don’t see many 20-year-old furnaces that are safe, efficient, and in good working condition.

Windows and Doors

Even a tiny gap like the one in this door can add up to huge increases in your heating and cooling bill.

If they work and are draft-free, don’t even think about replacing them. If they have storm windows, all the better. An old TIGHT window is much better and will last much longer than a new, poorly installed, cheap, smaller new vinyl replacement window (not that I’m opinionated at all). DRAFTS are what it is all about, rather than the ‘R’ or ‘U’ factor of the window. A small draft will totally wipe out any savings from a super-duper argon filled low-E triple pane custom vinyl window. Sealing or tightening existing windows is far more cost effective in most cases (Psst… Energy auditors are supposed to tell you about DIY opportunities FIRST before mentioning any upgrades or replacements…I’ve been through the training!).  And if you can see daylight around any outside doors, uhh…no. Weather stripping is MUCH cheaper than a replacement door.

I’ve just shared some secrets with you. If I get to an inspection site before the client does, these are the things I will look at while I am finishing my coffee. I haven’t started the inspection yet, but this “First Pass” has told me where I need to spend more (or less) of my time and given me clues as to what issues I should be looking for.

Maintain the Drain

One of the major causes of damage to a house is water infiltration. Your house should have systems in place to channel rainwater away from the house, and these need to be maintained.

This gutter is long overdue for cleaning out!

• Clean out gutters and inspect them for damage
• Check the roof for missing or loose shingles
• Make sure downspouts are free of debris
• Check that all downspouts have properly positioned splash blocks.
• Make sure any exterior drain grates are free of debris

Prepare the Pipes

Make sure that water flows where and when you want it to.

This hose bib isn't secured in the wall, leaving gaps for infiltration by air, water and critters.

• Turn on water to outside hose bibs and check for any leaks.
• Make sure water heater temperature is lower than 120 degrees.
• Check all hoses for cracks, leaks or pinholes.

Keep the Critters Out

Warmer weather means more insects, birds and other critters. Take the time to make sure they won’t set up housekeeping within your walls!

This gap in the brick siding has already become a nesting spot.

• Trim shrubbery so it doesn’t touch the house
• Check soffit vents for any holes or tears
• Check ridge vents for holes or tears

Clogged dryer vents cause fires!

• Check dryer vent outlet for debris or bird damage (it’s a favorite spot for nesting); clogged vents are the culprit in up to 30% of house fires. Read more about dryer vent safety.
• Clear dead branches from the roof and around the house

Plan on Energy Savings

The summer heat will be upon us before we know it, so now’s the time to prepare for it.

Clogged air filters rob your furnace of efficiency.

• Get your air conditioning system serviced now, before the rush.
• Change the air filter
• Check the attic insulation; adding more now will help keep your cooling bills down.
• Check for drafts with a stick of incense; caulk any gaps. Here’s how to check for drafts.
• Replace incandescent light bulbs with compact fluorescent (the newer bulbs are much better in mimicking the warmer incandescent light)

Be Mindful of Safety Issues

The warmer months mean lots of indoor and outdoor activity. Make preparations now to ensure that you’ll be safe this summer!

This deck railing is already pulling away from the wall and is a major safety hazard.

• Check all railings for stability. This includes interior stair railings, deck rails, and bathroom grab bars.
• Check your smoke detectors; you should have replaced the batteries when you changed your clocks to daylight savings time. However, if they are nearing 10 years old, it’s time to replace them.
• Add a Carbon Monoxide detector near sleeping areas.

Time for a Check Up?

Inspections by Bob does Maintenance Check-Ups! If you’ve been in your house for seven or more years, it’s definitely time for a check-up. Just like people, houses change over time as they age, and it’s important to make sure all the systems are working properly. Find out more about Maintenance Check-Ups!

Other advances

Multispeed indoor AND outdoor units are much quieter and save more money by matching the compressor and fan speeds to actual need. Additionally they also control humidity much better than single speed units.

There are also better filters (We like the 4” pleated) that work better but do not need to be changed every month and don’t generate Ozone like some of the Electrostatic unit.  UV Lamps in duct work serve to sterilize mold spores and pollen, further reducing potential allergens.

Modern thermostats are now typically programmable for setbacks during off periods and can even cope with larger setbacks without invoking the dreaded Heat-Pump Auxiliary Heat.

Compare the SEER ratings to calculate your energy savings.

How much you will actually save will depend on how you live, your thermostat settings,  the age of your equipment and more, but from the chart at left, you can see that the potential savings can be substantial.

As little as 8 years ago, SEER 8 units were still being sold and installed because they were cheap. It was only in 2006 that a minimum allowable SEER was mandated, and that was only 13.

Want to get an idea of what you might save? Take your HIGHEST electric bill and subtract your LOWEST. What is left typically represents your highest cooling cost. Then multiply by the appropriate factor from the table. You may not get that savings every month, but it gets the point across.

Last year, we had our furnace and heat pump units replaced, even though they were just ten years old. Since then, we’ve seen between 30%-50% drops in our electric bills. At this rate, the new system will have paid for itself within five years. Not a bad return on our investment!

Coming Up Next

There have been big changes in Refrigerator and Freezer efficiencies. You may want to unplug that old freezer in the basement after reading what we have learned! Look for that article soon!