Tuesday, April 30, 2013

DIY Mantlepiece #1

This post has very little (if anything) to do with the garden. Except for the fact that I often use my garden as my workshop — mainly because my wife doesn’t appreciate me mixing concrete inside the house — but that’s another story...

Let me start by explaining my problem. We finally decided to upgrade our TV from an old fashioned montrosity that was taking up a whole corner of our living room to a wall mounted 42 inch flat screen. The only suitable wall space available was directly above our fireplace.

I realised when we bought it at the end of last winter that this was going to be a problem next winter when we’d be wanting to use the fire again. I was worried that heat rising from the fire would damage the TV, so I started investigating ways of adding a mantlepiece to our existing hearth — something that would deflect the heat away from the TV.

To begin with, I looked into getting one made out of marble or something similar but the cost of doing so was going to be more than the TV itself (over $1000), which to me didn’t really make much sense. So I decided to build one myself out of concrete and then use tiles to match in with the existing hearth.

Our house was built in the 1950’s so the chance of matching the tiles perfectly was out of the question — I knew that. But it wasn’t just the colour and pattern at issue here but the size of the tiles which are an imperial size of 6 inches. Despite the challenge, I was amazed that I was actually able to find something pretty close at 150mm square which is about 3.5 mm smaller. The colour and pattern matched pretty closely too. To top it off I was able to get the 40 or so tiles I needed from a Tile Clearance Warehouse who stock all sorts of end-of-lines so they only cost me $10.

So I first set about finding some suitable timber planks which I had stored away under the house and which I used for building the boxing for the mantlepiece. I was careful to ensure the timber was straight with no bows or buckles in it and would be strong enough to remain straight under the weight of concrete which I estimated would be over 80 kilos.

I cut a piece of MDF to the shape and size of the end profile that I wanted and used that as the pattern around which I built the boxing.

Once the boxing was built I lined it with a bit of plastic, then tied together some reinforcing steel and set it in place ready for the concrete. You might also notice I added a couple of bits of timber moulding to create a channel where I planned to run the cabling for the TV.


Next, after making sure the boxing was level, I mixed up three 25kg bags of concrete and filled up the trough then smoothed the concrete over by eye getting it as flat and as even as I could, and working the slurry to the surface.

After the concrete had set, I removed the boxing and gave it a blast with the hose to remove any loose agregate. Then I got my mate Damian to give me a hand to carry it round to the front of the house where I would work on it further and get it ready for tiling.


  1. Good grief that looks like it's gunna be incredibly heavy. That reminds me, did yous get the video/phone link up for the Zone Meeting earlier in the year. I remember the bro from Bethel used an illustration of mixing concrete in the washing machine...

  2. Sorry I missed your comment Tony. Don't know how that happened. Anyway Yes, you're right. It was incredibly heavy, especially after it was all covered in ceramic tiles. I think I pulled a muscle lifting it into place, even though I had my made Damian helping me and he's a big strong fella.
    As for mixing concrete in the washing machine... I don't think I'd get away with that. Wifey complains enough already when I come inside with my gumboots on.