Do I need 2 lintels - fireplace

[Trickytree77]

Hi, I'm opening up a fireplace, the chimney goes off at an angle up as shown in pics. Do i need 2 lintels (one behind the other) as there will be nothing i can see holding up the bricks behind the lintel I'll be putting in. The red lines is the angle of the chimney.

 

[RonnyRaygun]

It's usual to insert some 10mm thick steel plates spanning from the lintel to the wall beyond to support the flue masonry.

Although that's usually if the chimney breast is being removed. Are you planning to use it for a fireplace in future?

 

[Trickytree77]

No, just opening it up wider, putting electric fire (log burner likalike) in. Just a bit concerned that there's nothing supporting the angled bricks/blocks behind the 100mm deep lintel. I suppose I could put another 2 concrete lintels behind (3 in total) or I could steel plate it. How do I set the plate in at the rear, do I chop out a ledge for it to slot in and set it in?

 

[^woody^]

The flue should be left open for ventilation which prevents your additional lintel idea or a plate - unless you want an air brick half way up the breast, or can achieve a suitable ventilation gap.

Lintel across the front, and smaller lintels at 90° tied into the main wall.

 

[Trickytree77]

Plan was to plasterboard the top and maybe the walls

 

[RonnyRaygun]

No, just opening it up wider, putting electric fire (log burner likalike) in. Just a bit concerned that there's nothing supporting the angled bricks/blocks behind the 100mm deep lintel. I suppose I could put another 2 concrete lintels behind (3 in total) or I could steel plate it. How do I set the plate in at the rear, do I chop out a ledge for it to slot in and set it in?

The flue should be left open for ventilation which prevents your additional lintel idea or a plate

I didn't mean a single plate - I meant plates supporting the masonry either side only therefore leaving the flue open. Works if it's just an electric fire going in there.

You would just need to chase a slot into a mortar joint about 40mm and then grout around the plate afterwards (or if easier fix a shelf angle to the wall and set the plates on that. In reality the brickwork should arch that short distance with no trouble anyway.

 

[^woody^]

Yes that could work