Re: What ladder for working on nine foot ceiling?
A fiberglass 6' ladder should suffice just fine. Go with fiberglass, as they're lighter and stronger, more steady than wood or aluminum, and they're non-conductive.
When you go ladder shopping, try out the different ladders. There are several classes of ladder that are designed for different weight loads, get the lightest ladder that will suit the needs of the user. Also, take a measuring tape with you. Go up the ladder to the safe working level (second step from top in most cases ), put your hand over your head and measure to the floor. If a 6' ladder won't work, then look at a 7' ladder. A 7' ladder will be slightly lighter than an 8' and infinitely more maneuverable in the house.
If you need a wider working area, then using two ladders as Canuk suggests is a good way to do it. Another would be to purchase metal adjustable height saw horses which can be safely used as a scaffold base.
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