Wet Basements – “The Ins and Outs”

Should there be concern when you and your client enter the basement of a prospective property and are greeted by a damp musty odour?

The simple answer is yes, absolutely. This odour is the common first clue that there is an ongoing moisture problem.

The musty odour you detect is caused by among things, mold spores, mildew, wet dust, standing water, rotting wood or wet carpeting. Any of these conditions can seriously affect air quality and potentially your client’s well-being and satisfaction.

Pervasive moisture may result in the deterioration of the structural integrity of the building by rotting columns and joists.

As Certified Home Inspectors, it is our job to detect the evidence of moisture, the extent, and the cause. 

The “Ins”

One of the first things to determine is the foundation type. In older homes, basements or “cellars” were never designed to be warm and dry. They were used to house heating appliances, plumbing, maybe some laundry facilities, root cellars and storage. Up until 50 or 60 years ago, lifestyles did not dictate basements to perform to today’s expectations. In homes built in the early 1900’s, crawl spaces with dirt floors with low ceilings were common. In the 1800’s, many residential foundations used stone and even large wood pylons as foundations

In general, stone, brick, and block basements will usually be damper and have more water penetration issues than poured concrete. All basements will have some moisture in the walls and certainly in the concrete floor. It really is a matter of degree of tolerance and how the space is intended to be used. Even normally dry basements may occasionally leak after a particularly heavy rainfall.

 A good moisture percentage metre will determine the amount of water present in a variety of building materials. It is used by Inspectors to locate and measure problem areas.

The next thing to determine is whether the water is coming through the foundation or is it coming from with-in the house?

Some internal sources of moisture are;

• Condensation of moist warm air on cold water pipes or windows
• Leaking plumbing or fixtures
• Backed up drains
• Leaking roofs, windows or siding
• Excessively high interior humidity levels
• Lack of ventilation
• Fixing leaks, ensuring the drains are working, decreasing humidity and increasing ventilation will help to dry out the basement. Water damaged carpets, wall board, and insulation all can hold moisture and should be removed.

The “Outs”

In Canada, load bearing footings must be constructed below the frost line. If the builder is excavating for the footings anyway, it makes sense to build a full basement. This means most residences have internal space below grade. Water tables, underground streams, roof downspouts and surface water all exert pressure (hydrostatic) against the outside walls of the basement.

Weeping tiles, grounds grading, window wells, waterproof coatings and membranes are designed to divert this water away from the hole in the ground which is the basement. If any of these systems is not functioning properly or is overloaded, then there will likely be seepage into the internal space.

Some external sources of moisture are;

• Low spots in the lot grading where water collects and pools close to foundation.
• Holes in drive ways or paths adjacent to the foundation.
• Excessive watering of flower beds and shrubbery close to the house.
• Leaking hose bibs, gutters and downspouts.
• Downspouts from the roof discharging within a 2 metre perimeter of the house.
• Surface run off directed towards foundations
• Cracks in foundation walls or floors allowing ground water to penetrate
• Vents to Cold Rooms too close to grade
• Basement windows close to grade or below without properly drained window wells

In some cases the best solution is to excavate the soil down to the footings, installing below grade drainage, wrapping the entire foundation in waterproof membrane and grading a 2 metre perimeter away from the structure. This is a major undertaking and simple, less expensive alternates maybe all that’s required.

Sump Pumps are being used more and more in new construction and when renovating. They are especially useful in areas with high water tables and areas that are prone to flooding.

Ensuring that the grading directs surface water away from the house, repairing hard surface holes, minimized planting close to the house, repairing hose leaks , managing rain downspout discharge, and sealing cracks in the foundation should all be considered before jumping directly to the conclusion that that a major waterproofing wrap project is needed. Understanding the cause of the moisture will provide the information necessary to make a proper decision.

A good first step is to consult a Certified Home Inspector to assess the situation, measure moisture levels, locate possible sources and advise as to how best proceed. With this valuable information your clients should be able to decide if the prospective home is the right one. 

Make it an easy decision.

Knob and Tube Wiring

Knob and tube wiring was the original internal wiring system installed in homes across North America.

The following information will provide insight into:

• ·         The Main Components
• ·         Buyer Considerations
• ·         Knob and Tube Advice

The Main Components

Knob and Tube (K&T) Wiring can be found in buildings built in the late 1800’s and first half of the 1900’s. It is sometimes referred to as “Open Wiring” because it consists of two wires, live and neutral, suspended throughout the structure with the use of insulating “knobs” for surface mounting and “tubes” for passing through wooden beams and other flammable barriers.  The copper strands are insulated with rubberized or asphalt saturated cloth. These systems were designed for a much smaller electrical draw (ampacity) than our usage requirements are today.  The original fuse type panel boxes were typically rated for 60 amps or less.

 Some potential problems occur when the system is improperly tapped into with additional circuits, the cloth wrapping material around the wires deteriorates or is broken, or walls and ceilings are insulated covering the components thereby trapping excessive heat in the wires causing damage.

Knob and tube wiring was eventually displaced from interior wiring systems because of the high cost of installation compared with multi-strand power cables, which combined both power conductors of a circuit in one run (and which later included grounding conductors). With most conversions, all traces of the K&T wiring is removed. Sometimes however, the old system is disconnected and left in place. This can be deceptive and should be tested for live current.

Considerations for buildings with K&T wiring

As existing K&T wiring gets older, insurance companies may deny coverage due to a perception of increased fire risk. Several companies will not write new homeowners policies at all unless all K&T wiring is replaced, or an electrician certifies that the wiring is in good condition. Also, many institutional lenders are unwilling to finance a home with limited ampacity i.e. 60 amp service (which, as noted above, often goes hand-in-hand with K&T wiring), unless the electrical service is upgraded.

Advice for those with K&T wiring:

• Have the system evaluated by a qualified electrician. Only an licensed professional should confirm that the system was installed and modified correctly.
• Do not run an excessive amount of appliances in the home, as this can cause a fire.
• Where the wiring is brittle or cracked, it should be replaced. Proper maintenance is crucial.
• K&T wiring should not be used in kitchens, bathrooms, laundry rooms or outdoors. Wiring must be grounded in order to be used safely in these locations.
• Rewiring a house can take weeks and cost thousands of dollars, but unsafe wiring can cause fires, complicate estate transactions, and make insurers skittish.
• Homeowners should carefully consider their renovation options before deciding whether to rewire their house.
• The homeowner or an electrician should carefully remove any blown-in insulation that is found surrounding K&T wires.
• Prospective home buyers should get an estimate of the cost of replacing K&T wiring. They can use this amount to negotiate a cheaper price for the house.

 Hopefully this information will help you and your clients better understand some of the factors involved with buildings where Knob and Tube wiring is present. If you suspect that a prospective property has live Knob and Tube wiring, have your home inspector verify its presence during the Home Inspection and discuss recommended next steps.