I want to install an attic ladder in the ceiling of our 1930s house. There is no ideal location in which the attic ladder would fit between the ceiling joists, so a joist or two will definitely need to be cut. There are also wires in the way. Questions I have:

  1. I've read that when joists are cut, trimmers need to be installed along the uncut joists that run along two of the sides of the attic door opening. Do the trimmers need to run the entire length of the joists to which they are fastened? Essentially, the entire width of the ceiling/attic?
  2. How can I safely relocate the yellow wires that are in the way?
  3. What are the white spindle-like objects with dark cord running through them, and can I remove them?

Location for attic ladder installation, two corners of one end marked by two screws, black gloves are sitting beside the screws

White spindles/knobs with dark cord

  • You can carefully remove the staples holding the wires in place with a large flat screwdriver and determine if there is enough slack to reroute them away from the opening. Play it safe and turn off the power to those wires while working with them. The white spindles and black wiring is what's left of the original wiring to your house. There is a chance the white and yellow wires have replaced this old knob and tube wiring but you'll have to trace it out to make sure it's not still hot.
    – JACK
    Nov 24, 2019 at 2:11
  • Are those ceiling joists 2x4? They appear to be small for an old non-truss construction. If so, I would definitely run 2x6s the entire width of the attic if you cut these. What is the ceilling joist spacing and joist size?
    – peinal
    Nov 24, 2019 at 15:08
  • @JACK Thank you! I'll kill the power and trace the wires to their sources. What would I do if there's not enough slack in the live wires?
    – JBR
    Nov 25, 2019 at 14:55
  • @peinal Thanks! They are 2x6, and they are roughly 26" on center, give or take a half inch - some have more space between them and some have less.
    – JBR
    Nov 25, 2019 at 15:06
  • If possible, you're probably going to want to install the ladder parallel to the joists not perpendicularly. Of course it depends on the "shape" of the house below, but it looks like that would prevent having to cut joists and also give more headroom at the top of the ladder.
    – gnicko
    Nov 25, 2019 at 16:15

2 Answers 2


I am certain you can obtain a folding stairway that will fit within your 26" spacing. A quick look on HomeDepot website shows a 22.5" and a 25" attic stair. So, you won't need to cut any existing joists, but will need to add end framing at the hinge and pull-down ends.

Be darn sure that none of that knob & tube wiring is energized or being used. If not, I would remove every bit of it. If so, you really need to replace it.

  • Thanks! The only reason I want to cut the joist is that the shape of the house makes it very inconvenient to place the ladder between the joists. I'll be very careful with the knob and tube y'all are talking about, may hire someone to do it for me.
    – JBR
    Nov 25, 2019 at 17:37

JBR, the white things are knobs and the tubes going through the wood are just that tubes for knob& tube wiring, since you don’t know much about electrical you may want to identify another location. It is quite possible the old wiring is still in use.

I have a 1930 farm house that almost all the K&T was still in use 5 years ago. Just a few new circuits that were NMB cables or Romex (a brand , the white and yellow cables)

Added reference: The NEC requires the protection of the wires per 320-23 , and NM cable refers to this section also 334.23

Be very cautious around the old K&T wiring that insulation is extremely old and I have been zapped more times than I can count crawling around in old homes with K&T.

If you add a permanent ladder you will also need to protect all the wiring, the Romex can have some boxes added and extended to get it out of the way but I would suggest a pro to do any work on the K&T if it is still in use , it can be done but not many sparkys will do patch work on K&T and some jurisdictions do not allow it.

  • That insulation on the K&T wires is likely so old that it will just fall off when handled or moved. You'll want to be very careful with it while you ascertain that is no longer in use. If it is in use, the best thing to do would be replace it before something bad happens to you or your house.
    – gnicko
    Nov 25, 2019 at 16:13
  • Thank y'all! I'll be very thorough and careful with the K&T.
    – JBR
    Nov 25, 2019 at 17:39

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