An extension on extension ladders
In his ladder safety pieces, Frank gave us a good background in ladder safety, including both step and extension ladders. In this “extension” on the subject, we will deal with a few addition pieces of information to make our use of extension ladders even safer.
Extension ladders are most often used to access the roof for sheathing, shingling, and other similar work. When we are getting on and off of the roof of the structure, whether new or one being refurbished, two key items to watch are avoiding damage to the roof edge (regardless of type) and stability for getting on and off – the ladder and the roof. Hopefully these hints might help.
Stability is an issue at both the top and the bottom of the ladder. Dealing with the bottom first, having a stable base is important as Frank pointed out. We don’t want to “block” one side of the ladder but, instead, find a way to “level the playing field” under the feet. One thing that can help is a ladder that has “spur plates” on the feet. These are cleats at one end of the moveable rubber feet on the ladder, and if they are present, the feet should be rotated so that the cleats dig down into the surrounding soil or surface – if anything other than pavement. While the moveable feet themselves are good, the spur plates are even better – and we would encourage affiliates to consider ladders with spur plates when making ladder purchases.
When spur plates are used, on other than pavement, the base of the ladder will be much more solid and less movable.
Now let’s talk about the top of the ladder. We need to affix the ladder to the roof edge/soffit so that it cannot move. A concern here is also to make sure that we don’t damage the roof edge, which could be metal edge drip trim and/or the overhang of a metal roof or shingles. The simplest way to do this is to construct a ladder block that is affixed to the house itself. This is done by using a 2X4 that is several inches wider than the ladder itself, to which we affix another piece of 2X4 that is the same width as the interior measurement of the ladder. Once this is constructed, it can be affixed to the house, either with nails to an unfinished soffit or with clamps. The wider piece keeps the ladder away from the edge to prevent damage, and the narrower piece holds the ladder so it cannot move.
Once the ladder block is in place, the ladder can then be put in place and it will not move side to side. I have seen some attempts to do this with nails on either side of the ladder, but those often can bend and are not nearly as secure.
|Ladder in place – note that the ladder is clear of the roof edge.|
What else needs to be done with this ladder placement? Read below:
The depth of the backer board can be increased, if the roof lip or other obstruction requires it, by adding additional backer board(s).
The ladder pictured is not tied off. Not shown in this example, but necessary per OSHA if the ladder will be used to repeatedly access the roof (ash in shingling operations), is to tie off the ladder so that it cannot come off of the block. One way is to placed a screw eye in the wider block on either side of the ladder rails and then use them to tie off the ladder to prevent it from falling back or raising above the interior ladder block and swinging to the side. Other means suitable to a particular structure may also be used. The tie-off is not shown in these pictures.
Movement from Ladder to Roof to Ladder
OSHA - Ladder minimum extension above roof is 3 feet. While a shorter ladder was used for the photograph so the block could be clearly seen, the extension ladder used should extend at least 3 feet above the roofline so that people can move from the ladder to the roof and the roof to the ladder from a standing position and holding the ladder without having to bend. More distance above the roof is fine, and taller folks may like 4 or 5 feet for ease of access. The goal – walk on/walk off!
Block your ladder, use the feet, and make sure it’s long enough.
Setting an Extension Ladder on Ground Sloping Ground
Reminder – If the ground slopes away from the house, the spur plates are not as effective as on flat ground. The base of the ladder should be braced against a 2x4 or better yet a 2x6 firmly seated to the ground and held in place with long metal foundation stakes so that it is firmly implanted.
Be careful to watch your angle. Remember the 4 to 1 foot rule. For every 4’ up the ladder needs to go out an additional 1’. Count this from the base of the ladder not up at the house level if the ladder base is below the house level.