im not sure but i think it may be call a dog house? the area the gas fireplace slides into, in the wall. anyway, i assume there is special insulation that has to go in there first. am i correct? if so what an does chicken wire have to be used to fasten it to the wall?
It doesn't have to be an special insulation. Just be sure there is none of the paper barrier left on for this application. Chicken wire certainly will keep the insulation from falling but it is probably overkill. I usually run framing scraps through a table saw to make lath strips of any convenient size and tack them up with a finish nailer about 14 to 16 inches apart.