I have a baby gate on the top of the stair. The dry wall anchors used held up for a couple of months, but now it came out loose. What type of anchor do I need to use for this?
What you are using are the most basic drywall anchors available. They're inexpensive and included in many products because of that, but they aren't good for much, and wouldn't be up to the task of holding something a toddler will be climbing on (you know they will...)
Look for products that spread out or lock into place when they enter the wall. The name of the product might have the word "toggle" or "lock" or "twist". There are several brands. Here is one random example:
For the strongest hold (and also a larger hole that must be drilled in the wall) Toggle bolts are hard to beat. I use them as a last resort because I've had great luck with plastic anchors and the hole these leave is large. Of course for something as important as a stair gate, it might be worth it.
Most things that get regularly manipulated should not be hung with hollow-wall anchors. Eventually they pull out or the wallboard disintegrates.
I'd install either some 1x4 wooden rails spanning between studs or a piece of finished plywood to which I'd mount the gate. Run construction or finish screws about 1" into the studs. Imagine the typical backer board for a coat hook rack for an example of what I'm describing. If a stud is very near you could use a 1x6 or 1x8 vertically, also.
Later, the holes will be much easier to fix than the large ones you'll have with your current solution.
Firstly you need a fixing the extends some distance each side of the hole, GripIt is one such fixing that is easy to use.
You then needs lots of fixings that are spaced out, therefore I would be looking to fix a bit of 3”by1” to the wall the full height of the gate using say 4 spread out fixings, then screw the gate hinges to the wood. By having both the bottom and the top hinges fixed to the same bit of wood, you will get less movement on the fixings.
Even better if you can find the studs and fixed to these, assuming that there are studs, e.g the plaster board my just be glued to the brick.
I know you have already selected a correct answer but these toggle bolts are the correct ones to use. They are very strong and they will allow you to take the gate on and off without diminishing their effectiveness.