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The Essentials of Sump Pumps

Incorrect terminology puts a real estate agent or homeowner at high risk.

When putting a home up for sale there are many details that are disclosed, sometimes, in a mandated seller disclosure report and other times for marketing promotions. If these features are overstated or not described correctly, liability and lawsuit risks will rise. There is no greater concern in purchasing a home than a wet basement. As a MN home inspector I too often see water control systems improperly portrayed. So let’s get the vocabulary and description correct.

Sump

The basket or pit that goes into the floor; it is typically about 3’ deep. In extremely high water table situations they can be up to 6’ deep. The sump is required to have a cover that is screwed down to protect kids and pets from drowning.

Beaver system

A plastic or metal diverter that sits on top of the basement floor slab. It is about 4” high and is glued to the foundation on the top and the floor slab at the bottom. Holes are drilled into the blocks allowing them drain and the diverter channels the water to either a floor drain or sump. This is not a drain tile system. It is an inexpensive, non-invasive, low quality method of managing wet basement walls. If the diverter glue fails the basement gets wet.

Drain tile

This is either a continuous plastic pipe with holes or clay pipe with open joints. Typically the pipe goes around the entire perimeter of the foundation below the floor slab and alongside the footing. Drain tile can be installed on the interior or exterior of the foundation and the pipes terminate in the sump.

Pump

This is an electrical pump that sits in the sump often called a sump pump. There is also battery pumps used to back-up the electrical pump if the power goes out.

Why is this important?

Can a house have just a sump? Sure, but this is not a drain tiled basement. It is just a basket in the floor. Is the beaver system the same as drain tile? No the beaver system is above the basement floor and the drain tile is below. A beaver system is an inferior method of water control. Can a basement be partially drain tiled or beavered? Yes and this is more common than you would imagine. To call a basement drain tiled you are implying the entire basement and that may not be true. Can a pump be discharged into the laundry tub? No sump pumps must be drain into the city storm drain or onto the yard. There is a stiff fine if caught dumping the water into the homes plumbing system. Does having a sump pump mean the basement is drain tiled? Absolutely not.

If you don’t know what you have, don’t claim it is something it might not be. That would make you easy pickings for a lawsuit.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI Certified Inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’ Rob Leslie
Kaplan Professionals, Retired

 

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3 Fire Proof Bypasses

Fire barriers are often compromised and the homeowner never knows it.

Home fire barriers have been a part of the building code since about 1960.  Homes built prior to that time were not required to have any fire protection and many different fire proofing methods have been added since then.  Fire safety is a big part of building codes as it should be.

Did you know that most house fires start in the garage?

Most of the time even old homes have been modernized with many current fire barriers in place.  Three of the most common breaches in the garage fire barrier are:

    1. Pull down attic stairs
    2. Clothes dryer and bath fan exhaust fan vents
    3. Furnace heat ducts

The bottom of attic pull down stairs is plywood and when closed this does not provide an adequate fire barrier.  The solution is to install fire rated sheetrock on the plywood cover.

For exhaust vents and heat ducts it’s as simple as extending the pipe through an outside wall and building a fire rated box around the pipe.

     

 

 

 

 

 

 

 

These simple garage improvements will protect the home against a fire entering the house.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI Certified Inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’ Rob Leslie
Kaplan Professionals, Retired

 

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Sewer Backup

Old houses can have underground sewer problems.

Recently, wise home inspectors and real estate agents have begun recommending that, in older homes, underground sewer pipes be videoed.  Most of these old pipes are clay and have a high probability of failure. Why…because of the many years of tree roots, soil settlement, road and driveway construction, and the properties of aged clay material. This does not mean all underground sewer pipes are the same. Depending on where you live, since about 1950 most underground pipes are made of cast iron or plastic. These pipes do not suffer the same type of damage that clay does.

As a part of a home inspection, the typical inspector will run the bathtub water for 15-20 minutes to determine if the sewer backups. But that does not mean the pipe is not broken, collapsed, or sagged. Remember that a home inspection is a visual analysis of the house and an underground sewer pipe is not visible. This means the inspector cannot be held responsible if a problem develops. This could be a huge cost risk, probably in the range of $10,000-15,000. By taking a video of the sewer line for approximately $150, home buyers can put this possibility to bed, before they buy the house.

Can you now hear the whisper of a bad sewer?

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI Certified Inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’ Rob Leslie
Kaplan Professionals, Retired

 

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Aluminum Wiring = Trouble

Because of the high cost of copper, electricians began using aluminum wiring between 1968 and 1974.

Determining that a house is wired with aluminum is not as easy as it may seem. You might start with determining if the electrical panel was installed during the period in which solid aluminum wiring could have potentially been used. After that only a seasoned home inspector or a certified electrician should check to see if the wiring actually is solid aluminum and if that wire has caused heat damage.

To start, you must look at the cut end of the wire to determine if it is a solid or coated wire. Silver wiring is not necessarily aluminum.  It could be copper wire with a tin coating. Similarly, copper wire may not be what it seems. Aluminum wiring was sometimes coated with copper to prevent a chemical reaction between the aluminum wire and its mounting hardware.

The main concern is aluminum wire alloys, produced in the period 1964 to 1981, expanded more than copper wire when they got hot and shrank more when they got cold. This continual expansion and contraction caused loose connections, overheating and eventually house fires.

What should I do if my house has aluminum wiring?

The best solution is to completely rewire the home. This can be very expensive, so there is a code approved alternative. Copper pigtails (a short copper wire) can be connected to the aluminum wires, creating a bond between the approved devices and the wire. This bond will stay secure and prevent overheating.

There are two devices approved to bond the copper pigtails to the aluminum wire. The best is a COPALUM connection which is a form of cold welding and can only be performed by a trained and certified electrician using specialized tools. This is a very costly process. The next best is AlumiCon connectors which are a newer, simpler and less costly alternative, to COPALUM. These devices also must be installed by a licensed electrician.  Amateur installation of AlumiCon connectors is not approved because improper bonding of the wire to the connector can cause serious overheating.

Never let anyone attempt to connect the copper pigtails to aluminum wire with a wire nut. This method has been extensively used in the past. It will absolutely cause overheating and maybe a house fire!  

Aluminum wiring is an issue that should be addressed immediately. Start by calling an ACI Certified Home Inspector for analysis.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI Certified Inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’ Rob Leslie
Kaplan Professionals, Retired

 

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Is That Room Legal?

Homeowners, realtors and home inspectors can have different views as to what constitutes a habitable room. Why does this matter? Because a converted room, such as a porch, basement, or attic, finished into “living space” may not be quite as livable as expected. So let’s have a look at it here.

According to the International Residential Code (IRC) and the MN State Building Code, habitable rooms are used for cooking, eating, living, or sleeping.

Because a room does not meet a habitability requirement does not mean it is not legal. The term habitability is misleading in that a room can be used for whatever purpose the homeowner chooses.  The following rules are guidelines for existing homes and requirements for newly built homes; a room must have:

  • Light – sunlight through a glazed window equal to 8% of the room floor area.
  • Ventilation – open able window equal to 4% of the room floor area.
  • Ceiling height – 7’ minimum.
  • Total area – 70 sf. minimum.
  • Width – 7’ minimum.
  • Bedrooms must have an egress sized window, but do not require a closet.
  • Kitchens are an exception – they do not need to meet the size or window requirements, but would then be required to have mechanical ventilation ducted to the exterior.

Non-habitable rooms are bathrooms, laundry rooms, closets, and hallways. These spaces are not required to meet any of the above requirements; however, bathrooms must have either a window or exhaust fan ducted to the exterior.

When purchasing a home or finishing a room be sure to take these rules into consideration, it could affect your investment.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’ Rob Leslie
Kaplan Professionals, Retired

 

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Let’s Look Closer At Deck Failure!

There are just two basic reasons for decks failing. The first is overloading and the second is improper construction.

Overloading: deck failure usually happens unexpectedly. We have been using the deck for several years, even barbecuing for the family without a problem. But today we are having a graduation party. Fifty teenagers’ crowd the deck which has never carried more than seven people! The music starts, the teenagers jump up and down, and the deck tears off the rim joist with the deck collapsing towards the house. Unfortunately several people are hurt.

What happened? Floor loads in a house are limited to 40 pounds per square foot or a point load of 300 pounds. That limit is designed to carry some furniture and people walking or sitting in the room. Decks are usually designed to the same limit so our deck was grossly overloaded with a large number of people on it, and absolutely could not carry the extra shock load of the teenagers’ dancing . The reason the deck failed where it is connected to the house (or the rim joist) is that this is the point where the entire load is perpendicular to the direction of the fastener. It is like suddenly smacking the fastener with an ax.

Party on the deck, by all means, but have it checked for structural integrity to be sure that the extra load can be carried. Pay particular attention to the rim joist, which should be bolted in a manner that pulls the deck floor joist and the house floor joist together. Proper hardware and an installation guide are available from your local big-box store.

Improper construction: every existing deck should be inspected to see that it has been properly constructed. Unfortunately, many contractors and local building officials do not appreciate that proper deck construction is even more important than it is in a house. The deck at some point will carry greater loads than the house floor and is being continually attacked by the weather where it has to contend with sun, rain and snow loads.

Any home inspector can determine if your deck is capable of carrying the loads required. Most often a contractor will be able to reinforce the existing structure without the need of building a new deck.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’ Rob Leslie
Kaplan Professionals, Retired

 

‘Like’ our Facebook page for interesting info on inspections and property issues!

 

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Wood Deck Failures

What happened to pressure treated deck lumber?

Pressure treatment is a process that forces chemical preservatives into the wood. The wood is placed in a closed cylinder and pressure is applied to force the preservative into the wood. Preservatives protect wood from decay and insect damage. There are 3 classes of wood preservatives; the waterborne method is typically used in residential construction. For decades the lumber industry successfully used CCA, chromated copper arsenate, as the preservative of choice. However negative publicity regarding the arsenate caused the wood product industry to voluntarily transition away from CCA to alternative preservative systems. CCA has no longer been used residentially since December 2003. A number of alternative preservatives are available. The most recognized are ACQ, alkaline copper quad, and CA, copper azole.

Testing has indicated that ACQ and CA are more corrosive to steel and the protective coatings applied over steel.

In other words, the old galvanized nails, screws, metal hangers and connectors were no longer approved for use with the ‘new’ pressure treated wood. Unfortunately, either nobody told the builders and lumber suppliers or they just didn’t care. Hot-dip galvanized or stainless steel fasteners and hardware are the recommended products to use. The structural stability of the wood deck depends upon using these approved fasteners.

When you see rusted nails, bolts, and other metal hardware on a wood deck, it is a big problem.

 

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’ Rob Leslie
Kaplan Professionals, Retired

 

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Decks Can Be Dangerous

Deck failures are becoming more common. Why do decks fail?

The most common reasons are:

  • Old age
  • Poor design
  • Improper materials
  • Overloading

Decks should be inspected annually. All lumber should be inspected for rotting, particularly where posts meet the ground, at joist unions, and the ledger board connection to the house. Most of this rotting is caused by old age, moisture, and lack of maintenance.

However, much of the rotting is coming from fasteners and connectors that are incompatible with the type of wood preservative the deck lumber was treated with. Rusted heads on nails, screws, or bolts connecting metal joist hangers are an indication that these fasteners or connectors have failed. This was caused by a chemical reaction between the metal hardware and the pressure treated wood. This form of failure is the number one reason for decks collapsing.

Unfortunately, there is great confusion as to which fasteners and connectors are to be used with what type of lumber. The best choice is stainless steel, but it is also the most expensive and difficult to obtain. The most commonly used nails, screws, bolts, and metal hangers are hot dip galvanized. These are a good, available, and lower cost choice. The thicker the galvanized coating the better and longer the metal hardware will perform. Other approved materials, similarly priced to hot-dipped galvanized, are silicon bronze and copper.

Deck collapses are often related to overloading or lateral movement. This two conditions place a great amount of stress on the deck fasteners and connectors. Therefore, whenever rust is seen on nails or screws, they should be removed for inspection or replaced.

Avoid a disaster inspect your deck each year.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’
Rob Leslie
Kaplan Professionals, Retired

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Choosing The Right Home Inspector

Look for Experience

American Society of Home Inspectors (ASHI) is the oldest national home inspection association. It has a stringent Standard of Practice which all members must adhere to. These comprehensive standards have been closely copied by all competitive organizations and state licensing laws. To become a full ASHI member you must have completed 250 paid home inspections and have each one reviewed by an association peer. This many inspections will take most inspectors 3 to 4 years to complete. Many inspectors don’t even make it through the first year and less than 10% make it to year five. Then to retain membership 20 hours of continuing education must be completed each year.

Look for Out for ‘Bogus’ Certifications

Unfortunately home inspection is a career that is more demanding than most people who enter the industry realize. Anybody can join a trade association and most have no requirements to be ‘certified’ by that organization. As long as the annual fee is paid, the association calls you certified, but this label is worthless as there are no standards to be met.

There are many excellent home inspectors who have joined associations other than ASHI or who have never joined an association at all. You could after doing your due diligence on an inspector choose one of them, and be perfectly satisfied with the result. However…

Look for True Certification

ASHI is the only home inspection association that has completed a recognized third-party certification process. They were required to adopt the most rigid standards and then verify that each member meet all the requirements. ASHI member qualification and professional competence is certified by an independent third-party.

Just the act of joining ASHI demonstrates that a home inspector is willing to meet the highest standards and is prepared to operate a professional business employing these standards of practice and meeting a stringent code of ethics.

A good place to start looking for an inspector is by seeking out ones that are ACI certified. This certification is not given lightly.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’
Rob Leslie
Kaplan Professionals, Retired

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My Ice Dams Are Really Bad

Icicles indicate the formation of ice dams. What do ice dams indicate?

Icicles form where water is dripping from the roof when snow is melting and the air temperature is less than freezing. Older houses are most prone to ice damming and large icicle formation. Recent building and energy codes addressed this problem and provided solutions. Assuming homes built in last 40 years are properly constructed, they have little to no problem with icicles. This is because the heat loss through the ceiling is small and warm house air does not reach the roof. Current roof ventilation design and adequate ceiling insulation will not allow snow to melt and refreeze as it crosses the cold overhang of the roof. This refreeze forms the ice wall that causes water backup under the roof shingles. This is also how the interior ceiling, wall, wood structure and insulation become water damaged.

Remember mold forms in building materials that remain wet longer than 48 hours. 

Today, what can be done about a problem that is knocking on the door? The only answer is to have the ice dam professionally removed by an insured contractor. However, the long term solutions is to have an expert assess attic insulation and ventilation levels, examine for proper roof flashing and shingle underlayment, determine if poor roof design necessitates using heat cables.

Converting roofs to meet a standard that will prevent ice dams is not difficult, but it can be costly. 

Begin the solution to your ice dam problem with an unbiased home inspector analysis. Or ‘Like Us’ on Facebook for more day to day information.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired

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Too Much Roof Snow?

Can my roof collapse from too much snow load? It’s possible, but highly unlikely.

Since about 1950, cold climate states must adhere to engineering principles that configure the structure of the roof. They are based upon the highest potential roof snow load in your area. The building code will then require the roof be designed and sized to safely meet or exceed those live snow loads. In Minnesota that load is 42 pounds per square foot north of a line that crosses the state just south of Hinckley. The south side of the line which includes Minneapolis and St Paul is 35 pounds per square foot.

How deep would the snow be if there was 35 pounds of snow per square foot on the roof?

Well…if it was light snow it would be 5 feet deep! If it was medium or normal density it would be 2.5 feet deep and if it was tightly packed, it would be more than 1.5 feet deep. The measurement by the way would be uniform over the whole roof. In the real world there will be places that are less deep or less dense. These include areas that are covered by roof overhangs, spots protected from wind, and behind chimneys and dormers. So, if your roof meets current code, you have little to worry about.

However, if your home is hundred years or so old or you have some reason to doubt that it has been built to code, you may wish to remove some snow. Remember though, if you are removing snow you are removing a very good insulator.

If you must remove snow use a roof rake with extension handles. Never stand on the roof or scrape the roof bare as this may damage the shingles. Be very cautious about letting someone who comes knocking on your door remove the snow from your roof. Check their credentials. Make sure they have insurance.

This could become a very expensive mistake!

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired

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Is Your Life Worth $25?

This very cold winter has been responsible for many accidents, including deaths from CO (carbon monoxide) poisoning. 

These disasters might have been averted if a properly located and operating carbon monoxide alarm had been installed. For just $25 a battery-operated or for $50 a hardwired alarm can be purchased and installed.

What is CO?  Carbon monoxide is a toxic gas that is tasteless, odorless, invisible, and none irritating gas. It also weighs approximately the same per cubic foot as the air in your house. If it is going to poison you, you won’t know anything about it!

What causes CO?  CO is a product of incomplete combustion due to an insufficient oxygen supply. This can occur by not supplying a fossil fuel burning appliance with enough air. Your furnace, water heater, fireplace, automobile either needs to be located in a wide open space or have an outside air supply. There are formulas for how big an open space is needed, but by installing an outside air supply you are assured of having sufficient air for complete combustion. Or carbon monoxide occurs when fossil fuel appliance burners are incorrectly tuned or when the burner exhaust system is blocked or leaking. In other words you are re-burning the original exhaust products. A safe appliance produces carbon dioxide (CO2). Only when there is not enough oxygen in the air or when you re-burn oxygen from the CO2 does the appliance become a CO producer.

All homes should have a CO detector within 10’ of all bedrooms.

What is the action level?  Obviously you would like to have zero CO in your house. But that may not be possible; you should expect a level of less than 15 ppm in your home. Exposures at 100 ppm (parts per million) or greater can be dangerous to human health. At this level the symptom would be a slight headache in 2-3 hours of exposure. People who survive CO poisoning and complain of low to severe headaches and nausea are lucky. They just got a relatively low dose of this insidious poisoning. Elevated levels of CO will simply kill you before you know anything about it.

All systems that burn fossil fuels… Oil, Gas, Wood… should be examined and tuned by an expert annually.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired

 

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6 Easy Steps To Reduce Radon

EPA does not recommend sub slab suction as the only way of reducing radon levels in your home.

In a real estate transaction there is limited time to test and mitigate radon concerns. Time is of the essence and contractual agreements must be completed. So typically when radon levels exceed the EPA guideline of 4.0 picocuries, buyers will demand a sub slab suction pipe and fan be installed in the home. This is an approved and proven method of reducing radon levels, but it is also the most expensive.

Radon gets into our homes when there are cracks and openings in the below grade foundation and floor slab or when the outside air pressure exceeds the interior building pressure. Understanding this opens up a savvy Realtor or homeowner to alternative, less costly, methods of mitigating high radon concentrations.

Try these before spending a lot of money:

Step 1. Get out a caulking gun; caulk all cracks in the floor and walls. Pay particular attention to the connections between the floor and walls, beam posts, sump basket, plumbing pipes and drains.

Step 2. Get on a ladder; make sure the top of the foundation walls do not have any cracks or open cores.

Step 3. If you have a sump basket, seal the cover shut and caulk the edges.

Step 4. Make sure there is no exposed dirt in the basement or crawl space. If so, those areas would need to be covered with 6 mil poly and the seams taped.

Step 5. Open furnace supply air registers in the basement and close off the returns. Turn the fan switch on your thermostat from auto to on. This continually circulating air will pressurize the basement.

Step 6. Re-test

This may be a good reason to have your home tested for radon before you put it on the market. It may save you some aggravation and money!

For more about Radon and other hot topics ‘Like’ us on Facebook!

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired

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Does Your House Breath?

I never had frost buildup on my windows before!

Like many houses my 1974 rambler was in need of attention.  For the past 5 years my justification for postponing the needed exterior maintenance was the bad economy.  I felt investing a large sum of money in the house was not wise.  Some of you may agree with this and some will not.  Regardless, at the insistence of my wife, last summer became the year of THE HOME IMPROVEMENT.  We contracted for new roof, windows, doors, siding, soffits and fascia.  Keep in mind to meet new state building and energy code requirements housewrap, window and door flashing, caulking, weather-stripping, and low E glass need to meet a very high standard of insulation and heat loss.  This old leaky house no longer leaked.  It is warm and comfortable inside, but this lack of breathability resulted in very large frost buildups on all of our windows and doors as soon as the weather changed.  Any home inspector would quickly recognize this as a problem that needed to be resolved now.  By ignoring this very obvious moisture sign, which many homeowners do, the next concern is going to be mold.  (http://bit.ly/19ut8aA)

I never had radon before!

But…it didn’t stop there.  As a MN home inspector radon testing is a big part of our business operation.   I had tested the basement previously and my radon concentration was at the minimum EPA standard of 4.0 picocuries.  Upon re-testing after the exterior remodeling was completed, my radon level is 3 times higher.  What is the lesson to be learned from these 2 events? (http://bit.ly/1huOoxd)

Houses work as a system.  By changing the exterior envelope of a home it will have a huge impact on how the interior functions.  What was never a problem yesterday may be a major problem today. 

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired

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What Is Ventilation?

Ventilation is not just air blowing in through an open window and it certainly isn’t the bathroom fan turned on to get rid of a bad smell. 

In a previous blog, I stated that many older houses are now much tighter than the owners believe. Remodeling, changing surfaces and even a coat of paint can do a lot towards tightening the house and reducing its ability to breath. You should, if you own a house that has new siding, exterior windows or doors installed, be concerned that there is an inadequate amount of ventilation. High humidity levels can cause all sorts of visible and concealed moisture damage to a home. Some clues are frost buildup on windows, ice dams, mold and wood decay.

Ventilation, broadly, is an equal exchange of stale air being continually exhausted from the house shell while being replaced by clean atmospheric air at code specified rates.

There are two general methods of ventilation:

  • The first is balanced ventilation. This requires design by an expert in the field. In balanced ventilation two fans of equal volume will be installed. One will suck air into the housing shell from outside and the other will blow stale air from inside the shell to the outside. Often the two air streams pass, side-by-side, through a heat sink material so that the heat being exhausted from the house may be captured and returned in the incoming air. Systems that employ this kind of heat exchange are usually about 70% efficient.
  • The other method is unbalanced ventilation. Unbalanced ventilation can be a fan sucking air into the house from outside and exhausting, by the pressure created, through an existing vent. Or, more typically, it would be just the opposite. Outside air would come in to the house through a lowering of pressure caused by an existing exhaust fan operating in the home. This method is not nearly as efficient as balanced ventilation but it will do the job.

The easiest and most economical way to ventilate your home is unbalanced ventilation. This is something that you can do yourself at a cost of a few hundred dollars. Some homes may already have the equipment in place and it will take little effort to implement. First you will need to select an existing exhaust fan in the bathroom or perhaps in the kitchen that is vented to the outside. Next, you need to create a vent opening in the basement, connect an insulated flexible air duct, and extend this pipe to the floor. The outside vent cover will need a screen to prevent vermin from entering the home. You may already have this pipe; it would be an open pipe near the furnace called an outside air supply. Finally, turn on the exhaust fan and run continuously. This will remove the stale warm moist damaging air in the home , replace it with fresh cold dry outside air and not depressurize the home. You are now controlling the quality and moisture level of the indoor air.

Any exhaust fan in the home will give you a result. Just remember that the smallest fan required by code is 40 CFM. The higher the CFM fan rating the quicker the home will complete a complete air change. Fans are typically rated from 40 to 130 CFM.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired

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