Can I rest a ladder against a window?

It seems like such a simple obvious thing to do, to lean a ladder against a window.

However is it incredibly dangerous and you really should never do it.

Like never.

It is really dangerous to lean a ladder against a window because the force of your weight on the ladder pushing against the glass using only the two feet at the top of the ladder is enough to make the glass crack or shatter.

You might be thinking that most of the weight from someone standing on a ladder is directed downwards to the base of the ladder.

Well, yes most of it is, but around 20% of the climbers weight is directed as lateral force onto the window pane, through the top points or feet of the ladder.

What will happen if I do lean my ladder against a glass window?

Well, a whole host of horrible things could happen, to put it simply :-

If the glass cracks or shatters from the pressure of the ladder weight – you could fall off the ladder from the sudden jolt in the ladder having no support.

You could also get showered in glass fragments or shards, which will be at head height.

You may even try to grab the window frame for support which may have remnants of the glass pane still attached – not good.

So, don’t do it – it’s not worth the risk.

So how do I get around this problem of not being able to lean my ladder against glass?

You have a few options:

  1. Lean your ladder against the brickwork to the side of the window.
  2. Use a longer ladder – one that will safely reach above the window pane.
  3. Use an extendable pole tool if you are doing a task which doesn’t involve hand tools – such as window cleaning.
  4. If you have climbing gear you could belay yourself from above – this is a bit more advanced though and shouldn’t be attempted if you don’t know exactly what you are doing.
  5. Rent or buy scaffolding – it may be expensive but extremely useful and much safer that trying to balance on a ladder. – A good idea if your project is going to run for an extended period.
  6. Invest in or borrow tripod ladder – these useful ladders have three legs and can stand freely without having to lean up against anything. – Perfect for reaching windows without having to actually lean on them.
  7. Get a ladder stabiliser – You can then lean your ladder safely over a window frame or to the side whilst being far enough away from the wall to reach. (An affordable ladder stabiliser just like the one below is available on
Can I rest a ladder against a window - no you should not.