More Blog Posts on Similar Subjects:

  1. How come my generator hookup got tagged as defective by the home inspector?

  2. Is the electric panel big enough for this house?

  3. Is there an adapter that can be placed on a two-slot receptacle to make it safe?

  4. Is this old home a Sears Catalog house?

  5. What is a split bus electric panel?

  6. What are the most common homeowner wiring mistakes?

  7. What is a ground wire?

  8. The electric panel is marked “Trilliant” and it’s all grey plastic. Is it alright?

  9. Why do you pay so much attention to electrical safety?

  10. What is a three-way switch?

  11. Why does that wall plug have push-buttons in the middle?

  12. Does this place have one of those “bad” electric panels I’ve heard about?

  13. Do you check the wall plugs?

  14. What is a “missing twistout” at an electric panel?

  15. What is an “open junction box”?

  16. How far apart should kitchen counter receptacles be placed?

  17. Why is the circuit breaker stuck in the middle?

  18. Why are Zinsco and Sylvania-Zinsco electric panels a problem?

  19. What is the life expectancy of electrical wiring in a house?

  20. What is a false ground, bootleg ground, or cheated ground receptacle?

  21. What are the most common electrical defects found in a home inspection?

  22. What is an open electrical splice?

  23. Why is an old fuse panel dangerous?

  24. What does it mean when a wire is “overstripped” at a circuit breaker?

  25. What is the difference between “grounded” and “grounding” electrical conductors?

  26. What is the difference between a Combination Arc Fault Circuit Interrupter (CAFCI) and an Arc Fault Circuit Interrupter (AFCI) circuit breaker?

  27. How can I tell if a receptacle/outlet is tamper resistant?

  28. What is a Dual Function Circuit Interrupter (DFCI)?

  29. Will a GFCI receptacle that is not grounded still function properly?

  30. Can an electric panel be located over stairs?

  31. Is a house required to have outdoor electric receptacles?

  32. What are the code requirements for NM-cable (nonmetallic-sheathed cable or Romex®) in an attic?

  33. How can I change a 240V circuit to a 120V circuit?

  34. Can old electrical wiring go bad inside a wall?

  35. Why are extension cords dangerous?

  36. What problems does having too many electrical outlets on a single circuit cause?

  37. How can I find out the size of the electric service to a house?

  38. What happens when you press the “TEST” button on a circuit breaker in an electric panel?

  39. How many electric receptacles (outlets) are required in a hallway?

  40. Why does painting an electric receptacle (outlet) make it unsafe?

  41. When were GFCI receptacle outlets first required?

  42. What is the difference between GFCI and AFCI circuit breakers?

  43. What causes flickering or blinking lights in a house?

  44. Why is bundled wiring in an electric panel a defect?

  45. What are the right words for talking about a house electrical system?

  46. What does “listed” and “labeled” mean for an electrical component?

  47. What does it mean when I find buried yellow "CAUTION" tape when digging a hole in the yard?

  48. How can I tell if the electrical service is 3 phase or single phase?

  49. What is the building code requirement for receptacle outlets at stairs and stair landings?

  50. Can a home surge protector be installed loose in the bottom of an electric panel box?

How to Look

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HOME INSPECTION
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Welcome to our blog!
We want you to be an informed homebuyer, and each blog post is a question that we have answered for our friends and customers over the years. Hope they help you make a good choice for your next home.

  Part of the problem with knob and tubing wiring that is still functional in a home is simply it’s age. The insulation is at least 70-years old, brittle, and flaking off. Another problem is the low current-carrying capacity compared to modern wiring, and difficulty in safely splicing K&T with modern electrical cable. Also, the NEC does not allow it to be buried under insulation or covered by any other stored materials. We recently found an attic full of “live” knob and tube, most of it buried under insulation at a 115-year-old house in Alachua. It’s  shown below, with a modern NM-cable running along between the two K&T wires.


    All knob and tube wiring systems are “two-wire,” meaning that they do not contain a third wire for grounding, which has been required for all residential electrical systems since about 1960. While K&T is now obsolete, and requires replacement when found during a home inspection, it’s worth noting that it was once state-of-the-art technology. We rarely see it anymore and, when we do, it’s in older downtown Gainesville neighborhoods like Duck Pond.


While we hope you find this series of articles about home inspection helpful, they should not be considered an alternative to an actual home inspection by a local inspector. Also, construction standards vary in different parts of the country and it is possible that important issues related to your area may not be covered here.
© - McGarry and Madsen Inspection

 

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