Would you keep all the windows open with the heat on in your car?

Bet you didn’t know you are heating and cooling a wind tunnel!

Certainly the biggest contributors to moisture in the attic are breakdowns in the building envelope. (Of course I am assuming that water is not getting in from outside the envelope–like a leaking roof) These compromises also make the building less efficient and will empty your wallet more as you attempt to heat and cool your home/tunnel.

air bypasses To understand this problem, it is helpful to think of one’s house like a Tupperware container. Clearly if we leave the lid a little bit ajar (like an attic access that is not weather-stripped), or start drilling holes in the bottom, sides and top, the container will no longer do its job–or at least less efficiently—relative to the number of holes, the size of the holes and where they are located.

Of course, if the holes are so the snake (or whatever else the kid catches) does not die, that is another matter.  It is still important to keep the lid on though.

There are other factors–but let’s keep it simple for today.

We can build the most super-insulated house in the world but if we don’t control air movement in and out of the building our efforts at insulating can be wasted.

One of the most common, obvious, everyday sort of “by-passes” that I see in homes is dampers in fireplaces that are left open. These chimneys will pull conditioned air from the home 24/7–with an occasional pause for atmospheric inversions that can happen. The screen on the fireplace filling up with lint is the first clue that this is happening. Even closed dampers in most cases will not stop this movement entirely.

Eliminating open flame solid fuel appliances altogether is a good idea in the context of building more energy efficient homes.

I have heard people argue that this natural draft is a good way to exchange the air in the home–without a mechanical fan. The truth is that this works–but at much greater cost than running a simple exhaust fan periodically. It is the 24/7 aspect of the chimney that makes it a problem, as it vents conditioned air that we are also paying for. On a windy day the venting might be much more than on a still day. We need “control” over this air exchange if we are truly going to control energy use as well as maintain a healthy indoor environment.

I want to stress that this is a LOT more complicated than I am willing to address here. For example rates of ventilation will not always guarantee good indoor air quality. While outside air is generally of better quality than indoor air, that is not always the case and in some areas of the country, outside air is becoming worse every day. At some point the political aspects of outdoor air quality will be forced to reconcile with the private aspects of indoor air quality. Some will argue that if you want “quality” drinking water you had better be prepared to solid-block-carbon-filter the water where it comes into your home. The same thing is perhaps coming for the air we are bringing into our homes.

Welcome to the 21st Century.

Back to air by-pass issues.

As previously mentioned, the attic access hatch is a common by-pass but the list is almost endless. Here is a partial list of some common breaches: plumbing pipes running through walls and ceilings, can-lights, HVAC equipment/ductwork in attics, crawl space hatches at the interior of the home, wiring holes in top and bottom plates of walls, chimneys, b-vents, improper framing techniques, skylights, pull down stairs, drop ceilings, exhaust fans etc.

“Stack effect” is something else that affects our homes.

Stack effect is relative to temperature/pressure differences. It is relative to the fact that warm air is buoyant. It is further driven by the lowering of pressures inside the home which then allows for air to be pushed into the lower levels of the home (from outdoors and/or crawl spaces). The taller the home, the more pressure differential as the buoyant air moves to the exterior (attic) of the home, bringing with it the moisture in the air. The colder the outdoor environment and the taller the building the more that hot air will be trying to get into the roof structure or outdoors to get to that cold. Perhaps the perfect storm is to have a leaky floor system over a vented crawl space in conjunction with serious breaches in the attic floor.

In this scenario you can think of your poor heating system as attempting to heat a wind tunnel. You will have to be willing to throw a whole bunch of energy at this wind tunnel in order to feel comfortable in your home.

In a very well sealed home there will be less stratification of temperatures and less “driving” of the stack effect–even when doors at the lower level are opened. Opening and closing windows on upper and lower levels in conjunction with each other is a way to manually control stack effect to change the air in the home. This is not rocket science, but can be as expensive as rockets.

At an inspection a while back I had one of the most egregious examples of a home with a functional wind tunnel. The defect was created when part of the forced air heating system was removed. If you could zoom in on this picture, you would be able to see the furnishings in the room below. There were three of these vents into the attic. The missing insulation around the vent is not even consequential in relation to this breach.

Closet vent open to attic

Closet vent open to attic

Sealing these air by-passes, even in older inefficient homes, can drastically reduce heating and cooling costs. Remember , heat tries to get to cold and high pressure moves to areas of lower pressure. So if the attic is really hot in the summer and we are cooling the home we have made the job of the AC unit all the more difficult. Better sealed homes accounts for why the size of heating and cooling systems have halved since the 40’s–remember—back when oil was free?

Sealing and eliminating all kinds of air by-passes is perhaps the most important thing we need to do in making our houses more energy efficient. Insulation alone will not do it and in fact in many cases will only filter the air as the air moves through it. This is especially true of fiberglass insulation–even 18 inches of it. All air by-passes must be found and sealed (or otherwise eliminated) prior to insulating. Choosing types of insulation that are in themselves good air barriers is also recommended.

By Charles Buell, Real Estate Inspections in Seattle

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New study finds that water runs down hill! Who knew?

Today is a day that will live in infamy as the discovery that water runs down hill was announced by a previously unknown kindergarten teacher in Seattle, Washington (obviously not the other Washington).

The teacher’s class of kindergartners, using standard garden hoses, Odwalla fruit juices and hamster slides, showed beyond a reasonable doubt that water does in fact run down hill. Before this day, this fact was obviously not known.

Because of how recent this discovery is, it is projected that there are still thousands of builders constructing homes unaware of the new information.

Many builders have expressed surprise at the way gravity affects water. Some even reacted with denial and accusations. Many were heard to say that the kindergartners, “don’t know what they are talking about—obviously!” Others remarked at how this information will be costly in the building of new homes from here on out.

Others called for further studies prior to jumping to rash conclusions.

Still others argued that government meddling in a free economy was likely involved. After all why shouldn’t someone be able to build a house any way they want regardless of what water does or does not do?

The very notion that flashings would now be required over any trim boards that are nailed on top of siding, above windows and doors, seemed just preposterous. But the fact that water was now known to be affected by gravity seemed difficult to reconcile with the industry standard of not installing any flashings at all. Is it any wonder that builders everywhere are crying foul?

Head flashing is missing

Head flashing is missing

Some builders, when shown pictures of the problem, merely argued for more caulk–although that did not seem to impress the kindergartners very much.

And caulking won't be good either

And caulking won’t be good either

It remains to be seen how this new information will affect home construction. Many experts belief that the information will be ignored and standard building practice will not be affected at all.

Only time will tell

By Charles Buell, Real Estate Inspections in Seattle

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Cat Scratch Fever (not all pre-listing inspections are created equal)

There is a recent move for sellers to not only have pre-listing inspections done, but to use the pre-listing inspection report as a means of promoting the sale of the house.  This includes, in some cases, the sale of that report to prospective buyers for a small fee.  This helps the seller recoup the cost of the pre-listing inspection and maybe even make some money on it. 

Other approaches amount to the inspector doing the inspection for free and the payments from prospective buyers goes to the inspector.

In my opinion these models, and other similar ones, are fraught with problems.

Despite this, there are so many good reasons to get Pre-Listing Inspection done on your home when you are planning to sell your home.

The reasons most sellers are discouraged from having pre-listing inspections done, has to do with “disclosure” issues. 

Once the cat is out of the bag, they do not go back in quietly or safely. 

It does not seem to matter that sooner or later the seller is going to get scratched by the cat, but the thinking is that there is the “possibility” or “hope” the buyer’s inspector will not find the cat and the seller can ride off into the sunset financially better off.

I think it is better for any possible cats to be found beforehand, so that they can be properly de-clawed, and the home can be improved in the areas that might prevent a sale—or narrow the field of potential buyers.

This is a really good idea if the entire house has been used as a climbing pole and litter box.

There is always a buyer for any house—but are we really thinking about selling it to someone that is just going to tear it down?  That will likely make you the least amount of money—but then again it might be accurate.

A pre-listing inspection can be meaningful in starting the conversation about what the house is REALLY worth—perhaps the seller has unrealistic expectations that need to be brought into perspective. 

Perhaps the cat just needs to be put out of its misery—or merely petted nicely.

As compelling as the idea of pre-listing inspections might be to a seller, they should be of zero interest to a buyer, other than to maybe give them a clue as to whether they want to make an offer. This makes even more sense in a really hot market where there are going to be a lot of offers.

They should NEVER be a substitute for their own due diligence.

There are questions as to who owns responsibility for the report and its content once the report is sold.  Since the inspector has a contract with the seller and not the buyer, the buyer certainly cannot “rely” on that report for anything.

This would seem to add potential liability on the seller–or whoever is selling the report that is not likely even a home inspector.

Sure the “fine print” will say that the pre-listing inspection is not a substitute for a buyer’s due diligence,but there is a real danger the consumer will not know these reports do not satisfy their due diligence.  Under the pressure and the heat of the moment, and without reading the fine print or any encouragement to read the fine print, the buyer can make one of the bigger mistakes of their life.  Is it in the vested interest of the agents and seller to communicate clearly that the pre-listing inspection does not satisfy the buyer’s due diligence?

I caution any buyer, to not rely on these pre-listing inspections solely to make their decision.  If the report is inaccurate or incomplete and you “rely” on that information there will likely be no recourse because you do not have a contract with the inspector that did the report.  Most reports go out with very specific expiration dates and who can rely on them.  The further these reports get from who they were done for the less value they have.

There will be no way to put the cat back in the bag—and there may not be bandages enough if you try.

By Charles Buell, Real Estate Inspections in Seattle

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