How To Look At A House

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What are the most common problems with older houses?

Thursday, October 25, 2018

We love old houses and have owned homes from the 1930s, 1950s, and 1970s, along with remodeling homes of every vintage for clients, including 100-plus year old wood Victorians. Gainesville has homes dating back to the beginning of the twentieth-century and beyond, with an abundance from the 1950s and ‘60s era. Old houses seem to have more character, and evoke the style and values of another era--which can be especially charming.

   But all that charm and history comes with a price: unless the house has been recently updated by the previous owner, you can get stuck with quite a bill bringing the home up to something resembling the standards of the 21st century.

   It’s rule of thumb in the construction industry that a building has approximately a 50-year useful life. After 50-years, even with the best maintenance, a home needs replacement of all major systems and appliances. Also, several building materials that were once considered safe are now recognized as hazardous contaminants.

   Here’s a list of 15 things you and your home inspector should be on the lookout for in an older home you’re considering buying, beginning with the electrical issues. But, if you are concerned about the likely problems of a home built from a certain era, skip to the bottom of this page for links to articles specific to each decade from the 1940s through the 1990s. 

1) Knob-and-tube (K&T) wiring was an early type of residential wiring, used between 1880 and the 1940s, with the wires stretched between porcelain insulating tubes. Today’s building codes do not require that it be removed, but most insurance company’s will not insure a home with K&T wiring still in place, and the wiring suffers from overheating, unsafe modifications over the years, and lack of a ground wire.

2) Screw-in type fuse panels, the kind with little round fuses with a window so you to tell if it’s blown, are considered obsolete. They typically have ungrounded circuits and, because the fuses of different amperage ratings are interchangeable in the older boxes, easily over-fused. Again, most insurance companies will not issue a policy on a home with a screw-in fuse panel still in use. Visit our blog post Why is a fuse box/panel an insurance problem for homebuyers? for more on this subject.

3) Undersized electrical service is another problem in older homes. When a family only used electricity for a refrigerator, a radio, and a few lights around the home, the size of the electric service coming into a home was smaller. Service is rated in amps, which is a measure of the amount of current flow/workload the system can handle. The first standard was 30-amps, then 60-amps in the 1930s and 40s, followed by 100-amps in the 1950s and 60s. An electric meter for 60-amp service is shown below.

    Today most residential electrical service is 150 or 200-amps, in order to accommodate the major electric appliances: range, water heater, air conditioner, furnace, washer, dryer, and dishwasher, just to name a few. If you want all the modern appliances in your older home, you may have to upgrade the electric service. To learn more, see our blog post How can I find out the size of the electric service to a house?

4) Non-grounded receptacles were the standard before 1962, have only two slots, and are missing the round hole for a ground connection that many modern appliances with a three-prong cord need. A ground provides a route for stray electric current that improves the safety of the appliance and, if you don’t have any three-slot receptacles in the home, you can’t safely plug in a modern refrigerator, for example. “Cheater plugs” that hardware stores sell to enable a three-prong cord to connect to a two-slot receptacle are an unsafe solution—because there is rarely any ground connection from the securing screw of the cover plate—that we see all to often.

5) Not enough wall receptacles is another problem in pre-1950 homes. It is not unusual to find only one receptacle per bedroom and none in the dining room or hallways. Running extension cords around the walls is not a safe fix. More circuits and receptacles are necessary for our homes filled with electric gadgets today.

6) Lack of ground-fault-circuit-interrupters (GFCIs), in homes built before the late 1970s, leaves you without modern shock-protection in the wet areas of the home, like the kitchen and bathroom.

7) Lack of insulation means higher utility bills than a newer home. Vintage homes were built with non-insulated single-pane windows, no wall or floor insulation. Minimal attic insulation that has compressed and deteriorated over the years, losing a significant portion of it’s original R-value, along with deteriorated or missing insulation on attic ducts—like in the photo below—can also contribute to higher utility bills.
    Air leaks around door and window openings due to deteriorated caulk may need to be repaired. While most older homes have had new attic insulation retrofitted at some point, floor insulation in homes with elevated floors is rare, like in the bare underside of an old house wood floor shown below, and wall insulation—because of the difficulty to install—almost never happens.

8) Inefficient older HVAC systems also contribute to low energy efficiency in an older home. A 20+ year-old central air conditioning system has a SEER (energy efficiency) rating of 9. As the SEER number increases, the energy usage for the same amount of cooling drops proportionately. This means that a new 14 SEER system is about 50% more efficient. Newer gas furnace systems are also more energy efficient.

9) Buried fuel oil tanks are often abandoned and forgotten when homeowners switch to newer fuel sources. Long-term corrosion causes tanks to leak into the surrounding soil, and poses a safety hazard. Disposal guidelines typically call for removal of the tank or filling it with sand and gravel. Soil testing may also be necessary to determine if the tank has leaked underground. A buried fuel tank has a fill pipe and a vent pipe, like in the picture below, except that the fill pipe cap is missing in this photo.

10) Lead is a toxic metal that was once commonly used to make household paint and plumbing fixtures. While it has been banned in new construction for many years, lead-based paint and plumbing that aren’t removed may present a significant health hazard. Homes constructed prior to 1978 may contain lead paint (although use was significantly reduced after 1960), which can be ingested by small children or contaminate surrounding soil and vegetable gardens. It is easily identifiable by its alligator-like flaking pattern. Lead pipes, too, were used in homes up until the late 1940s, and they may allow lead to leach into drinking water. They can be identified by their dull gray color and the ease by which they can be scratched by keys or coins.

11) Asbestos insulation can increase the chances of developing lung cancer and mesothelioma. Loose-fill insulation was used in homes between 1930 and 1950. Asbestos insulation should be left undisturbed until it can be removed by a qualified professional, as its fibers can be inhaled when they are airborne, creating a significant health hazard. Asbestos siding and roofing, while not a threat as long as the materials remain undisturbed, also require removal by a qualified, professional asbestos mitigator when it’s time for replacement.

    While loose-fill asbestos insulation represents a greater risk, the more common type of asbestos insulation found in older houses is vermiculite, which contains asbestos fibers in the material. Zonolite was the most popular brand, and it was sold in the U.S. up until 1990. It is sometimes concealed under newer fiberglass batt insulation, like in the photo below. To read more about it, see our blog post Why is vermiculite attic insulation a problem for both buyers and sellers of a home?

12) Galvanized steel water pipe was used from about the 1930s through the 1970s. Unfortunately, it has only a 40 to 50 year lifespan due to corrosion. It’s easy for a home inspector to locate and show you bubbling rust scars on old galvanized piping, but the real problem is on the inside of the pipes where loose flakes of rust accumulate behind fixture valves and cause reduced water flow. Eventually, the pipes rust through from the inside-out and begin to spring leaks. Also, many insurers will not issue a policy on a home with galvanized steel water supply piping.

13) Cast iron drain pipe was used up until about 1975, when it was replaced by the newer plastics like ABS and PVC. It has an average lifespan of approximately 60 to 70 years and corrosion holes cause leakage of sewage at the end of its lifespan, typically along the bottom surface, and allow tree roots into the system.

14) Foundation problems are more prevalent in older homes simply because the soil underneath them has had more time to move. Also, trees have grown large in the yard over the years and roots extending under the home may have created additional foundation defects.

15) No smoke alarms were required in an earlier era, and some homeowners have neglected to install this very important safety device. 

   The good news is that many older homes have already resolved most, or all, of these problems. But, if you miss just one of the major ones during your home inspection, be prepared for a big headache later.

    If you wan to learn more about evaluating older homes for potential rehabilitation, click below to download HUD’s Residential Rehabilitation Inspection Guide.


    Also, see our blog post How do you determine when the house was built? 

• • • • • • • • • • • • • • • • • • • • • • • • • • • • 

    To read about issues related to homes of particular type or one built in a specific decade, visit one of these blog posts:

• What are the common problems of 1920s houses?

What are the common problems of 1930s houses?

What are the common problems to look for when buying a 1940s house?

What are the common problems to look for when buying a 1950s house?

What are the common problems to look for when buying a 1960s house?

• What are the common problems to look for when buying a 1970s house?

What are the common problems to look for when buying a 1980s house?

What are the common problems to look for when buying a 1990s house? 

• What are the common problems to look for when buying a house built in the 2000s?

What problems should I look for when buying a country house or rural property? 

What problems should I look for when buying a house that has been moved?

What do I need to know about buying a foreclosure? 

What should I look for when buying a former rental house?  

What problems should I look for when buying a house that has been vacant or abandoned?

What are the most common problems with older mobile homes?

What should I look for when buying a house that is being "flipped" by an investor seller? 

What do I need to know about a condo inspection?

What are the "Aging In Place" features to look for when buying a retirement home?

   Visit our HOME INSPECTION and COMMON PROBLEMS pages for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.

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