Hi all,

While I initially posted this on the Home Repair forum, it did not get any responses, so I thought I'd try here. I'm a bit stumpered on how best to proceed, and am looking for feedback on what we're thinking, alerts to any pitfalls, and to find out what I don't know that I don't know. :-)

Background:

1880's Queen Anne house. In the dining room is a radiator, surrounded by a mantelpiece unit, and behind that interior wall of the room is a chimney running basement to roof. I've been stripping off the wallpaper on the rest of that wall, and noticed that what was behind the radiator was a sheet of some type of wood covered in wallpaper and nailed in place behind the radiator. While I couldn't move the panel out without moving the radiator, due to a leak elsewhere in the hot water system, the system was drained and I had the plumbers disconnect and move the radiator over so I could get the panel out and paint it to match the rest of the wall.

Discovery:

I had thought it was going to be a flat wall behind the radiator. Instead, there is this niche that's pretty much the width of the chimney I measure in the basement:

Niche space is:

About 19" wide

37.5" tall

3.5" deep

Our current thoughts:

- Radiator is 38.25" tall and 32" wide. It pretty much fills the space under that mantel unit except for about 3" on each end.

- My husband would like to put a sheet of aluminum to reflect the radiator heat back into the room. The sheet is 36"x36", and would cover up the niche and fill most of that area within the mantel unit. He figures he can nail it into place with small nails into the vertical beading pieces, and then the radiator will hide that when it goes back into place.

- If it were only up to me, I might do something different. However, his idea seems the least effort and he's motivated to do it, and I can't think of reasons *not* to do it that way. (And I suppose we could always change it in the future if it's just the sheet of metal there.)

My questions:

- Do we need to fill up that niche with some material before putting the aluminum sheet across it? Or can it simply exist as an air space behind the aluminum sheet?

- Any safety pitfalls about having this aluminum sheet up against the plaster walls on either side, and against the vertical wooden beads?

(I'm assuming it would only heat up to the heat of the radiator, which I can rest my hand against.)

The oak floor boards run up to the plaster wall that you see in the pic (both on either side of the niche and inside the niche), and they end at the wall.

Any other pitfalls/hazards that we should be concerned about?

Thanks in advance for your insights and feedback! We're aiming to get this done this week, so if there's some safety thing that we should take into account, I'd appreciate hearing about it.

--Lee