Joist Hanger Installation Defects

Just a little over a year ago, I took a class put on by one of the largest manufacturers of metal brackets, Simpson Strong-Tie.   That class was a real eye opener – I realized afterwards that just about every deck that I inspect is constructed wrong.  Not all of the installation defects are major, but they’re always worth pointing out.  Today I’ll talk about one of the most common installation defects that I find with joist hangers in the Twin Cities – improper nails.

You thought I was going to say missing nails, didn’t you?  Too easy, too obvious.

Wrong Nails If the wrong nails are used at a joist hanger, it won’t perform as intended. To know what nails are supposed to be used, you first need to know what joist hanger you’re working with.  The most common joist hanger I find on decks is a LUS28*.  This joist hanger can be used with 2×8 and 2×10 joists.  Now that I know which hanger I’m using, I can go to the Simpson Strong-Tie web site to find out what fasteners are specified.  To see the full page I’m looking at, click here.

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As you can see, this hanger requires 6-10d nails + 4-10d nails.  The big defect that I often find is that 10d x 1 1/2″ nails are used in place of 10d nails.  If you look down on the far right column of the above chart, you’ll notice only a few hangers will allow a 10d x 1 1/2 nail.  So what’s the difference between the two? Quite a bit!  The photo below shows the two next to each other.

Now here’s what the nails would look like if driven in to the floor joist.  You can see that the smaller nail isn’t long enough to even begin to penetrate the ledgerboard.  Click the photo for a blowup.

The really crazy thing about this is that the nails that are so much smaller are actually called “Joist Hanger Nails”!  They’re called joist hanger nails because that’s about the only thing they’re good for… but they’re usually not even good for that.   If you go to Home Depot and you look at their joist hanger display, you’ll probably find boxes of joist hanger nails sitting with the rest of the joist hangers, and no other types of nails. I’m pretty sure that’s why these nails get used improperly so often.

To identify these “Joist Hanger Nails”, all I need to do is look at the head of the nail.  They all have a big “10″ stamped on them.  Standard 10d nails don’t have this.

How serious of a problem is this? The manufacturer will allow these nails in to the header, but the total load will need to be reduced to 64% – a huge reduction.  The manufacturer does not allow these nails in to the joist.  I sent the manufacturer two separate emails to find out what the reduction factor would be if they were used in the joist, but after ten days, no reply.

I meant to make today’s blog about all of the different defects that I find with joist hangers, but this one defect just ended up being enough for a full blog.  More on joist hanger defects later.

* Joist hangers meant to be used outdoors or in contact with treated lumber will often have “Z” at the end of the model number.  In my example, the joist hanger used for a deck would actually have a model number of LUS28Z.

Reuben Saltzman, Structure Tech Home Inspections - Email - Twin Cities Home Inspector

A Missing Jumper Wire At The Water Meter

One of the most common electrical defects that I find while doing Truth-In-Sale of Housing Evalutions in Minneapolis is a missing jumper wire at the water meter.  This is a required repair item, and I often find the repair done improperly, so I’m writing this blog to help anyone that has to fix this item.

To start, here is the wording that TISH Evaluators are supposed to follow, which comes directly from the Minneapolis TISH Evaluator Guidelines (2008):

A) There must always be a jumper wire installed around the water meter. Bonding jumpers shall be of copper or other corrosion-resistant material, have approved clamping devices and be of the correct wire gauge for the service installed. If this jumper wire is not present or is not properly connected on either side of the water meter, (or only the street side, when the water pipes are Pex or similar materials) or is not installed with approved materials, mark as RRE. Be specific on what work is needed

A jumper wire is used to electrically bond the water distribution pipes throughout the house.  The purpose of bonding the water distribution piping in the home is to make sure they can’t accidentally become energized.  If an ungrounded (aka – hot) conductor came in contact with a properly bonded water pipe, the current would have such a good path back to the main panel that it would overload the circuit breaker and the breaker would quickly trip.  In other words, it protects against electric shocks.

A much more important reason that Minneapolis requires a jumper wire at the water meter is that it was once acceptable for the electric service to use the water distribution piping in the house as a grounding conductor.  I couldn’t find any great diagrams that showed this type of installation, so I made my own crude diagram.  Don’t make fun of my drawing – I know I’m no artist or architect!

And here’s a photo of what this looks like.

The problem with this installation is that if the water piping gets disconnected, the electric panel is no longer grounded to the water piping.  That’s why this installation is no longer acceptable.  Many old homes in Minneapolis are still wired this way, so it’s especially important for the jumper wire to be present at these houses.

If there is any other break in the water distribution pipes (ie – plastic water piping, plastic water filter, water softener, etc), there needs to be a jumper installed.  For a blog specifically talking about this topic, check out Seattle Home Inspector Charles Buell’s blog on jumper wires.

The photos below show what a proper jumper wire should look like.   While some TISH evaluators require the bonding clamps to be placed on the outsides of the shutoff valves (vs right next to the meter), I don’t.  This might be the preferred method, but that’s all – it’s not a requirement.  As always, click the photos for a larger version.

For more information on common Truth In Sale of Housing defects, click on any of the links below.

• Smoke Detectors
• CO Alarms
• Vacuum Breakers (backflow preventers)
• Toilet Ballcocks
• Floor Drains

Reuben Saltzman, Structure Tech Home Inspections - Email - Truth in Housing Evaluator

How To Correct Double Tapped Circuit Breakers

Double tapped circuit breakers are one of the most common electrical defects that I find while doing home inspections in Minneapolis and Saint Paul, and they’re usually one of the easiest defects to correct.  Today I’ll explain what double tapping is, when it is and isn’t a problem, why it’s a problem, and how to correct this condition.

I didn’t consult an attorney before writing this article, so I feel like I should add a disclaimer before giving any electrical how-to advice:  Don’t do any of this work if you’re not qualified.  This is only an overview.

Definition: I don’t know of any official definition of a ‘double tap’.  This is just what us home inspectors say when two wires are connected under one screw or terminal inside an electric panel.  Sometimes this refers to two wires at one circuit breaker, other times it refers to two wires connected under one screw at the neutral bar.  Today I’ll be focusing on improperly double tapped circuit breakers.

When it’s NOT problem: Double tapped wiring is ok if the circuit breaker is designed for two wires.  If a circuit breaker is designed for two wires, it will say so right on the circuit breaker, and the terminal of the circuit breaker will be designed to hold two wires in place.  The circuit breaker shown below is designed to accept two wires, and I highlighted and blew up the portion of the label that tells me that two wires can be attached.  This is acceptable.  To my knowledge, the only manufacturers  that make circuit breakers that can be double tapped are Square D and Cutler Hammer… but not all of their circuit breakers can be double tapped.

When it IS a problem: This is a problem when the circuit breaker isn’t designed for two wires.  The label on the circuit breaker will clearly state this.

Why it’s a problem: If the circuit breaker isn’t designed to hold two wires, the wires could come loose at some point in the future, even if they feel very tight today.  Loose wires can lead to overheating, arcing, and possibly a fire.

How to fix: The fixes I’m going to list below are a few common ways of dealing with double tapped circuit breakers.

Pig Tail This is usually the easiest and best repair.  The offending wires simply get disconnected from the circuit breaker, connected to a single wire with a wire nut, and that single wire gets connected to the circuit breaker.   Now, I know what you’re thinking: “What’s so tough about that?”  The answer is nothing.  This is a quick and easy fix.

Different Circuit Breaker Another simple repair would be to replace the circuit breaker with a type that is designed for two wires, as long as the panel is designed for it.

If there are more problems going on besides just a double tap, the repair might get more involved.  For instance, if a homeowner finished off a basement and added a circuit for the basement bedroom on to the circuit breaker for the bathroom receptacles, simply adding a pig tail for the wires wouldn’t be a proper repair, because the bathroom receptacles can’t be on a shared circuit.   In this case, the wires would need to be split off on to two separate circuit breakers.  There are a few ways to do this.

Add A Circuit Breaker If there is room in the panel, another circuit breaker can be added, and the wires split off to the two different circuit breakers.

Install A Tandem Breaker If the electric panel is designed to use tandem breakers, and a tandem breaker can be properly used in lieu of the offending circuit breaker, this is another acceptable fix.  Some people refer to tandem breakers as half-height or half-size breakers.  This is basically a way to install two circuit breakers in one slot.

If a panel will accept tandem breakers, it will say so inside the panel, and the specific locations where tandem breakers can be used will be identified.  A panel may allow all tandem breakers, notandem breakers, or some tandem breakers.  The photo below shows a panel that allows some.  As you can see, eight more circuits could be added to this panel, as there are currently no tandem breakers being used.

When none of the above solutions are possible, the repair might involve replacement of the panel with a larger one, or the addition of a subpanel.  This would obviously get much more expensive.

Reuben Saltzman, Structure Tech Home Inspections - Email - Minneapolis Home Inspections

Are High Efficiency Furnaces Worth The Extra Money?

In my blog about window replacements, I made it clear that you’ll never get a return on your investment by replacing windows.   So what about furnaces?  If you’re replacing your furnace, is it worth installing a high efficiency furnace?  We’ll see.

Reuben's Old Furnace

I’ve already compiled the data from my gas bills going back to 2004 on my Minneapolis home, so this should be pretty simple to figure out.

• I use an average of 520 therms per year to heat my house.
• The average cost of gas in my area has been $0.90 / therm, making my average annual heating cost $468.
• The average life expectancy of a furnace is about 15 – 20 years.
• My current furnace is 80% efficient, meaning that 80% of the fuel that gets burned is turned in to heat.  The other 20% disappears up the vent.
• For this example, I’ll use a 95% efficient furnace, which also qualifies for a tax rebate.  This should give me a 15% savings per year, as compared to an 80% efficient furnace.

Saving 15% per year on my heating costs equals out to $70/year.  If the furnace only lasted 15 years, I would end up saving $1,050 over the life of the furnace.  Because I would qualify for the tax credit, I’d also get 30% back from Uncle Sam.

I’ll assume that the 95% efficient furnace costs about $4000, including installation, but I’ll get 30% back, making the total investment $2800.  The 80% efficient furnace would cost about $2000.   This means I would end up paying about $800 more for the high efficiency furnace, but I would easily recoup those costs over the life of the furnace.

That seals the deal – my next furnace will be a high efficiency furnace.   If my next furnace lasts longer than 15 years or if gas prices go up in the future, I’ll save even more money.  The more you spend per year on heating costs, the faster the payback period.  Besides saving money, using a high efficiency furnace is a green thing to do.

RELATED POSTS:

• Gravity Furnaces
• Moisture Problems Associated With High Efficiency Furnace Installations
• Furnace Certifications Might Be Useless
• A Frustrating Story About An Improper Furnace Installation

Reuben Saltzman, Structure Tech Home Inspections - Email - Minneapolis Home Inspections

One More Ice Dam Removal Method – Blowtorch

This is a follow-up to my blog post on How To Remove Ice Dams.  Several people suggested using a blowtorch, and I thought it would be easiest to just follow up with a video. Sorry for the lousy sound quality – I didn’t want to use my good camera on the ladder.

Reuben Saltzman, Structure Tech Home Inspections - Email - Minneapolis Home Inspections

RELATED POST: How To Prevent Ice Dams

How To Get Rid Of Ice Dams

Last year at about this time I wrote a blog about ice dams, covering what needs to be done to prevent ice dams from happening, both on the inside and outside of the house.   This year I’ll discuss a bunch of different ways to get rid of ice dams.  The methods involve axes, ice picks, pantyhose, salt, and heat cables.

Axe

The most obvious way to get rid of ice dams would be to just take a blunt instrument and hack away at the ice dams.  I tried an axe.

Pros: Fast results – I hacked through several feet of six-inch thick ice dams in a matter of minutes.

Cons: Unsafe and cumbersome.   I had a set up a ladder on the icy ground and swing an axe while standing on a ladder.  The ice also really flew in my face – I should have been wearing goggles!  I was only able to remove the ice down to the gutter, and only able to get close to the surface of the roof without risking damage to the shingles.

Verdict: This is a high risk, but fast and effective way of getting rid of a lot of ice, but leaves the job incomplete.

Ice Pick

Sounds like a natural choice, doesn’t it?  I actually used my awl, but close enough.

Pros: Very fast results, very little effort.  It’s as though this tool was made for picking at ice.  Oh, wait…  Still, I was genuinely surprised at how fast and accurate this method was.

Cons: Unsafe.  Again, I was jabbing at ice dams while standing on a ladder, which was sitting on the icy ground.  I also had to be very careful to not damage the roof.

Verdict: This is definitely my method of choice.  Nothing else worked nearly as well.

Roof Tablets

Yes, this is a product designed specifically for preventing damage from ice dams.  Contrary to the name on the container, the product doesn’t actually melt your roof (whew).  The instructions say to toss the tablets on to your roof and they’ll melt through the ice dams, allowing for “water to drain safely”.

I tried tossing the tablets on the roof like the instructions said to do, but it didn’t work out very well.  I consider my tablet tossing skills to be above average, but I still couldn’t get the tablets to end up in a good location – they all just slid together in one place.  If I didn’t get a ladder out to take pictures, I never would have known that the tablets didn’t end up in a good spot.

Just to give the roof melt tablets the best possible chance for success, I hand-placed them on the ice dam and I used about four times as much as the directions called for.

By day two, I had some pretty dramatic results – the tablets had melted all the way through the ice dam.  btw – for anyone in a southern climate that might be reading this blog, that white stuff on the ice is snow, from a very light snowfall the night before.

By the third day, not much change.  There were definite holes in the ice dam, and some channels had formed for water to drain through, but the majority of the ice was still there.

Pros: If you had perfect aim and tablets didn’t move after you tossed them on to the roof, this would be very safe.

Cons: The tablets don’t stay where they land, which negates the whole safety thing – I still had to set up a ladder on the icy ground and move the tablets around myself.  This method was also pretty ineffective – it created a bunch of holes in the ice dam, but so what?  Most of the ice dam was still there in the end.

Verdict: This might be a nice way to get down to the roof surface, and it would be nice to follow up with an ice pick after a day or two, but the tablets alone aren’t great.  Sure, it’s safe… but so is sitting inside a warm house.  Neither gets the job done.

Salt Filled Pantyhose

This is a simple, straight-forward approach.  Take off your pantyhose, fill ‘em up with ice melt (calcium chloride or something similar), and toss ‘em on your roof.  The idea is that the salt will leak through the pantyhose and eventually melt the ice dams away to nothing.   This is supposed to work better than just putting salt directly on the roof, because salt applied directly to the roof will just melt a bunch of tiny holes, much the same way the tablets melted large holes.

By day two, there were several tiny holes in the ice dam.  Whoop-de-doo.  Salt alone would have done this.

By day three, the pantyhose had started to melt in to the ice dam, and had completely melted down to the roof.   The part that hadn’t melted down to the roof basically had a hard, crusty layer of salt(?) formed on the bottom of the pantyhose, and nothing else was happening.  I picked up the pantyhose, broke up all the chunks of stuck together salt, and placed it back down.

On day four, I tried moving the pantyhose again to loosen up the stuck together chunks of salt, and the pantyhose ripped apart, leaving a big mess of salt on the roof.  Yuck.

Pros: This is pretty safe.

Cons: Took way too long and didn’t do much.  Waste of time.  I wonder if I can return the pantyhose to Walgreens?

Verdict: Better than nothing.

Heat Cables

For the record, heat cables aren’t supposed to be placed directly on ice dams, but some people might try it anyway.  My friend did this at a house he owns in Saint Louis Park… so I took pictures.  These photos all show the heat cables after about one day.

Note the creative way of keeping the cables from touching each other.  Pretty cool, huh?

Pros: Gets the job done, and will prevent the formation of ice dams throughout the rest of the year.

Cons: Heat cables aren’t made for this, and I’m sure the manufacturer would tell you that this poses some type of safety hazard.  Stringing up the cable was also very unsafe.  It’s a good thing my friend owns a jet pack.

Verdict: Don’t do this.

Summary

An ounce of prevention is worth a pound of cure.  My favorite method was definitely the ice pick, but this was also very unsafe, and there’s a good chance that the roof surface could get damaged this way.  I’d rather not have to deal with ice dams at all.

After a good snowfall, rake the snow off your roof.   This definitely takes the least amount of effort and it’s safe.  I’ve been asked whether a roof rake will damage the roof, and the answer is definitely no.  A good roof rake will have little wheels at the bottom of the rake , which prevents the bottom of the rake from even touching the surface of the roof.  Rake away.

Reuben Saltzman, Structure Tech Home Inspections - Email - Minneapolis Home Inspections

RELATED POSTS:

• How To Prevent Ice Dams
• Using A Blowtorch To Melt An Ice Dam

HRVs, Part 3 of 3: Installation Defects

For the last two weeks I’ve blogged about HRVs. In part one, I covered what HRVs are for and how they operate. For part two, I covered HRV maintenance and operation. Today I’ll discuss installation defects.

The most common defect I find with HRVs is that they were never balanced. When HRVs are installed, a technician needs to balance the system to make sure the air getting exhausted is equal to the air coming in. If more air comes in than what goes out, you’ll have a pressurized house… and vice versa. Neither of these conditions are good for the home.

To make sure an HRV is balanced, I look for a balancing sticker and I check to make sure that the balancing damper controls have been screwed in place. If they’re not screwed in place, a balancing sticker means nothing. If I don’t see a balancing sticker, I don’t make a big deal about it, but I’ll often make a note in my report that it’s missing. If there are no balancing screws, I recommend having the HRV professionally balanced.

Most HRVs are installed hanging from straps or chains and springs to minimize the transfer of any annoying vibration from the fans. If an HRV gets mounted to the wall, I check the installation manual to make sure that this is an acceptable installation, and I listen on the other side of the wall to see how loud it is. When they’re mounted incorrectly, they can be very noisy!

As a rule of thumb, the intake and exhaust locations at the exterior of the home should be located at least six feet away from each other. I’ve never seen an installation manual that allowed anything less. It’s also important to make sure the intake is at least ten feet away from any sidewall vented gas appliances, such as a powervent water heater or furnace. The intake should also be located at least ten feet away from anything smelly, such as where the garbage containers get kept.

The ductwork that feeds the intake from the exterior and exhaust to the exterior needs to be properly insulated. If it’s not properly insulated, you’ll feel an obvious cold draft.

If the HRV ducts are only attached to the furnace’s return air, they must be at least three feet away from each other, and the furnace’s blower fan must turn on with the HRV to prevent the air getting added to the house from short-circuiting and getting pulled back out of the house. Every manufacturer recommends connecting the furnace’s blower fan to the HRV for optimal performance, but it’s not always a requirement.

Every HRV needs to be plugged in to an outlet. If the HRV is running off an extension cord, this is an improper, unacceptable installation. Repair requires the installation of an outlet.

That’s about all of the HRV installation defects that I can think of, and that concludes this mini-series on HRVs. As always, please email or post any comments or questions!

Reuben Saltzman, Structure Tech Home Inspections - Email - Minnesota Home Inspections

HRVs, Part 2 of 3: Maintenance & Operation

Last week I blogged about why houses need HRVs.  This week I’ll write about maintenance and operation of HRVs, and I’ll try to cover the stuff you should know if you own one.  The information in this blog is general – every manufacturer will have their own set of instructions and their own maintenance schedule.

Maintenance

• Every three to six months the filters should be cleaned by vacuuming to remove as much dust as possible, then washed with warm water and mild soap.  Some filters can also be washed in the top tray of a dishwasher, but this may tarnish the aluminum finish.  The filter below should have been cleaned a long, long time ago, and this is what I find at almost every home inspection – way more than dirty furnace filters!

• Every three to six months Clean the condensation tray with damp cloth.  The condensation tray is the area where water will collect in the bottom. The condensate drain should be checked, and replaced if needed.  The drain tube usually consists of clear plastic tubing with a little loop that creates a trap to prevent odors from the floor drain or wherever else from getting sucked in to the HRV.

• Every three to six months Check the intake grill at the exterior of the home to make sure it’s clean.  These get very dirty, as there is a fan constantly pulling air in.

• Every six to twelve months the core should be cleaned by removing it and letting it soak in a mixture of lukewarm water and mild soap.  Rinse the core thoroughly when done.  If you own a summer core, don’t get it wet, as you’ll cause permanent damage to it.  Summer cores can be cleaned by vacuuming with a brush attachment.

• Every one to three years the fans should be cleaned.  This typically requires removal of the fan assembly.  Check the owner’s manual for specific instructions, or hire a professional to do this.

Operation

Operating an HRV is usually quite simple.  If the HRV has a switch located on the unit itself, it will typically have a couple of the following settings, but not all:  On, High, Low, Off, or Remote.  If your HRV has a “Remote” setting, you’ll probably want to use that one. This will allow the HRV remote controller, usually mounted on the wall next to the thermostat,  to turn the HRV on and off.  This remote will also typically have a dehumidistat, which controls how much moisture is in the air.

If the bathrooms in the house have funny little wall buttons instead of bathroom exhaust fan switches, it typically means that the HRV system has had ductwork installed in the bathrooms.  This is an acceptable alternative to bathroom exhaust fans.  When the wall button is pushed, this will turn on the HRV for somewhere between 15 – 60 minutes, or will kick the HRV in to high gear for 15 – 60 minutes.

Every HRV should also have a defrost cycle, and the HRV should go in to the defrost cycle automatically when it gets too cold.  The defrost cycle is actually quite simple; the exhaust fan just runs for about five minutes, which forces a bunch of warm indoor air through the core without bringing in any cold air.

If you plan to operate your HRV during the summer, check your owner’s manual to see what the manufacturer has to say about it.  If your HRV is designed to run during the summer, you’ll probably need to remove the standard winter core and install a summer core.  The difference is that the summer core is designed to remove moisture from the air coming IN to the house, rather than the air leaving.  If there is no mention in your owners manual about running your HRV during the summer, you probably shouldn’t.

That’s about all for maintenance – for any more specific instructions, you’ll need to check your owner’s manual.  Next week I’ll talk about installation defects.

Reuben Saltzman, Structure Tech Home Inspections - Email - Minneapolis Home Inspections

HRVs, Part 1 of 3: Why Houses Need Them & What They Do

Many months ago I wrote a blog about how houses can often have moisture problems when old furnaces are replaced with high efficiency furnaces. The fix that I mentioned at the end of the blog was to install a Heat Recovery Ventilator, or HRV.  The character in that blog finally got around to installing an HRV in his house, and solved all his moisture problems! For the first time since he installed his high efficiency furnace, he no longer has condensation on his windows during the winter, and he couldn’t be happier about it.

Today I’ll share some basic information about how HRVs operate and why they’re needed in today’s newer, tighter houses.

New Houses Don’t Breathe As most people know, new houses are constructed much tighter than they used to be – they don’t leak air all over the place.  I’ve heard a lot of old-school home inspectors and building contractors complain about this, and you probably have too.  The rant goes something like this: ”We build houses so damn tight that they don’t breathe, and they end up rotting from the inside out!  Things were a lot better when we didn’t have all these stupid house wraps.”

These cranky doom sayers are only partially right – yes, we build houses tighter today, but we’ve also figured out how to prevent mold and moisture problems, and how to improve indoor air quality.  This is where HRVs come in.

HRVs Provide Fresh Air An HRV works by constantly bringing fresh air in to a house and exhausting stale air.    The air that gets brought in to the house gets passed through a screen at the exterior, then through a filter inside the unit, then through the HRV core, which is actually a heat exchanger.  The heat exchanger allows the fresh outdoor air to get warmed by stale indoor air right before the indoor air gets exhausted to the exterior.  This allows about 60 – 80% of the heat in the air to be re-captured.  The diagram below illustrates this principal.

To understand how an HRV works, interlock your fingers together and picture warm air flowing through fingers in one hand, and cold air flowing through the fingers in the other hand.

HRVs Remove Moisture Besides providing fresh air, HRVs also remove a lot of moisture from the air.  Old, drafty houses get dry in the winter because they’re leaky, and the moist indoor air is always getting replaced with dry outdoor air.  Not so with newer houses – they stay humid during the winter, and HRVs are often needed just to get rid of all the excess humidity.  As the warm, moist air passes by the cold air, the moisture will condense.  This is why HRVs have a drain running out the bottom.

HRVs Lower Radon Levels Because HRVs constantly change out the air in a house, an HRV will reduce radon levels when working properly.  During a recent Eden Prairie home inspection that I also performed a radon test at, I had the HRV running during the majority of the radon test, but I tripped the GFCI outlet for the last hour of the radon test during my inspection.  Look at the jump in radon levels at the house from NOT having the HRV running!  Any time a radon test is performed, if there is an HRV present at the house, it should be up and running throughout the duration of the radon test.

HRVs Have Many Names If you hear any of these terms, someone is probably talking about an HRV:

• Air-to-air heat exchanger
• Air exchanger
• Whole house ventilator
• Big square thingy in the furnace room
• VanEE system (brand name)
• ERV

The last one, ERV, stands for Energy Recovery Ventilator.  These are similar to HRVs, but ERVs are pretty rare here in Minnesota – I think I’ve seen two of them, ever.  They’re designed for more humid, southern climates.

If you don’t have an HRV at your house and you think you need one, you could always just turn on an exhaust fan and leave it running.  This will be very inefficient, but it will change out the air in your house.  I call this the Poor Man’s HRV.

Next week I’ll talk about the maintenance needs of HRVs, and the week after that I’ll discuss installation defects.

Reuben Saltzman, Structure Tech Home Inspections - Email - Eden Prairie Home Inspections

New Windows Are Nice… But You’ll Never Get Your Money Back.

I’ve heard some pretty outrageous claims from window replacement companies.  The most common ‘hook’ for selling replacement windows is that you’ll get a Return On Investment  (ROI) because of all the money you’ll save on your heating bills.  In the real world, the idea that you could ever come close to breaking even on your investment for new windows is impossible at best, and borders on downright dishonesty.  Unfortunately, a lot of consumers believe the window company’s claims – I hear this myth repeated many times while doing home inspections throughout Minnesota.

To prove this, I decided to figure out how much money I would need to save every year if I just wanted to break even on the investment of new windows at my house, assuming the windows could last thirty years… although the average life expectancy for replacement windows is actually twenty years.   I’ve already replaced nine of the twenty-two windows in my house with newer energy-efficient windows.  If I replaced the remaining thirteen windows with incredibly energy efficient windows and I only paid $500 each, I would have to save 46% on my heating bills every year for the next 30 years just to break even!

• I use an average of 520 therms per year to heat my house.
• The average cost of gas is $0.90 / therm, which makes the average cost to heat my house every year $468.
  

  Reuben's Gas Bill

A few details about my house:

• Built in 1939, 1500 finished sf, 1 1/2 story.
• 2×4 construction, most walls have about 2″ of rock wool insulation.  This means the walls are very poorly insulated, so a lot of my heat loss is happening through the walls.
• Basement is completely unfinished and uninsulated.
• Attic / 2nd floor is insulated with about 3″ of closed-cell spray foam.
• Thirteen original single pane windows with removable storm windows installed during the winter.
• Nine newer Low-E windows (the kind that are supposed to save energy)
• I keep my house at 72 degrees during the winter, and I use a setback thermostat.

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Assuming each new window costs $500, replacing thirteen windows would cost $6500.  To save $6500 over a period of 30 years, I would need to save $216 per year on my heating costs, or 46% or my average annual cost, which is $468.  In reality, I might end up saving somewhere around 5%.  I’ve already replaced almost half the windows on my house, and I haven’t noticed any significant savings on my heating bills.

I’m not writing this to discourage anyone from replacing their windows –  I love new windows, and I dislike my old windows with a passion.  They’re a huge pane to maintain, and I’m slowly replacing them… but every time I replace a window, I do it because I like having new windows, not because I think I’m going to save any real money on my heating bill.  A $1500 tax credit still wouldn’t even get me close.