... where the rain gets in (with apologies to Lennon & McCartney).
I need to fill a hole in a garage floor. But it's an odd situation, and I'm not sure what the proper way to do it is. I ask here with much trepidation: tried to find answers locally, but I have no "go-to" guy (or gal) I can get good answers to these kinds of questions from. So I'll take my chances here. (If you *must* speculate without actually knowing what the hell you're talking about, go ahead: I'm hoping to get at least one or two answers from knowledgable people.)
The garage floor in question is actually above a room below. It's in a hilly part of Oakland; the garage is level with the road in front, but the ground slopes down sharply, and there's a room built below the garage. (The garage is actually only a roofed area with no walls.) The occupants are planning on finishing the room below, so this hole needs to be filled first.
There's a hole built into the floor, apparently made for the purpose of working on a vehicle from below. (Kinda weird, as it's almost 8' above the floor, requiring a ladder to reach.) It's covered with a wood (2-by) cover. The cement slab, which is about 4" thick, has a ledge molded around the edge of the hole to hold the cover in place.
The hole is about 3 by 4 feet.
The end result needs to be able to support the weight of a person or an automobile. It will probably *not* be driven over much (the existing cover is never driven over by the current occupants of the house), but it obviously needs to be able to withstand this weight.
Climate is mild, rarely freezes.
Sketches:
o Drill holes into the edge of the slab, using rotary hammer & SDS bit. o Epoxy rebar dowels into the holes, long enough to overlap at least 18" or so. Bind the dowels together with wire. (How many dowels? spacing?) o Add wire mesh over rebar? (What type?) o Add new joists across the short (3') dimension of the hole, using joist hangers, plus cleats at the edges. (The existing hole is completely framed by joists.) Two new ones should do it, giving a spacing of about 16". o Place plywood (1/2"? 3/4") on top of the joists and cleats. o Pour concrete into the hole. Finish top surface smooth to match existing floor.
So, whaddya think? Will this work? I'm not sure I'm up to finishing the concrete myself: learned that skill years ago on a construction crew, but I'm not at all in practice. But the rest I can do.