Fireplace opening

[tireetim]

I'm opening up a fireplace so that a stove can be fitted. The chimney is concrete blocks. I've started removing the red bricks which I though were just decorative as they sit in front of the wall and also line the opening. I have got to a concrete lintel behind (picture 2) but it only has about 60mm overlap on each side. My question is can the red bricks that line the opening be fully removed or is the lintel relying on the red bricks for support? 60mm seems like a small bearing for the lintel (although it looks like the lintel hole was made for 100mm overlap and the lintel was cut too short). The span would be 815mm without the red bricks.

 

[ree]

OP,
Before you go any further you would be best advised to select a burner and take the Mfr's installation dimensions from the burner's handbook. Then work to those dimensions.
Come back here if you need a bit of advice?

 

[tireetim]

Thanks ree, that is what I have done but anyway I want the red bricks gone. Just trying to establish if they are supporting the lintel or not.

 

[ree]

OP,
If you already have the dimensions then what are they?

 

[tireetim]

Hi ree, I don't really understand what you are getting at - why do you need the dimensions? I just want to open the fireplace to the builder's opening and want to know if the red bricks are structural or decorative. Ideally I want to remove the ugly red bricks exposing the concrete blocks behind them and then line it with hardiboard or similar. I was just suprised to see that the lintel looks like it's partly being supported by what I think are decorative bricks.

 

[Alastairreid]

Don't see any problem removing the facing brick it won't go anywhere, personally I would put a longer lintel in unless you are bricking it back up to suit the required opening.

 

[stuart45]

A rule of thumb for a lintel of that size is a minimum of 100mm bearing on each end. Longer lintels need 150mm. However, I've seen plenty of lintels like yours that seen to survive with only a couple of inches each end. Would agree with Alastair though, it's probably worth sticking a longer one in now that you've got this far with the work.

 

[ree]

OP,
The dimensions would show if your existing lintel was suitable for the Mfr's recommended opening.

 

[tireetim]

Thanks alastair and stuart. I think I will replace the lintel with a slightly longer one to give 100mm overlap and at the same time raise it up a bit. Two more questions if I may :
Will the blocks be ok unsupported briefly while I install a new lintel - I don't have any sort of acro prop that short.
Will a 65mm high x 100 deep lintel be sufficient. The existing one is 145 high and 110 deep.

Thanks.

 

[Alastairreid]

No problem removing that lintel without propping..cut the pockets for the new lintel before removing the old one if you have the room.
65x100 no problem.

 

[tireetim]

Thanks Alastair, that is a great help.

 

[ree]

.

 

[mrrusty]

What do you think that lintel is holding up? - Yes, a triangle of blocks above - what's that 3 blocks? maybe 6? Leave it as it is, it's going nowhere.