Mounting a 2.5M awning to rendered brick wall - 2 brackets enough?

[JimboMarimbo]

When the awning arrived, I was struck by how heavy it was - nearly 19kg in its packing and 17 kg unwrapped. Supplied with just two 35mm mounting brackets and 4 x 100mm expansion bolts, the instructions make it very clear that these will only work if fitted into 12 or 14mm holes in solid brick - not mortar.
My Edwardian Essex terrace has all its brickwork covered in 1970s render and masonry paint, so it is impossible to see where the line of bricks/mortar joint s are. I'm guessing the only accurate way to fix the brackets is to chisel away an area of render large enough to find two adjacent bricks suitable for central drilling of the two vertical bracket holes, per bracket. If there is a less damaging way that a pro would adopt, I would be grateful to hear it.
Finally, two brackets, four bolts and 17kg downforce on a 2.5M width, with maybe 25% of the weight projecting outwards by 2M - really? Will this be structurally sound?
Pictures of the brackets, intended internal mounting position, and awning included here.

 

[footprints]

I put up a similar one https://www.primrose-awnings.co.uk/...q_session_id=c4b1b1aef65032eaa74765f431b3fade and purchased an extra bracket for the centre.

I also found those expanding plugs tended to split the brick (I have strange brittle bricks that naturally have cracks in the face) I went with chemical anchors in the end. Mine was 3m but had four fixings on each bracket. Yours is shorter but only has two, an extra bracket might be a good idea.

London yellow stocks are a soft brick too, shame they are rendered they look great when freshly re-pointed.

 

[JimboMarimbo]

Thanks for that - your experience of similar is useful to know. For peace of mind I think I'll spring for another central bracket as they are the two holes per bracket versions.
Worrying to hear about the expanding plastic plugs, I was hoping they would be an improvement on those Fischer expanding metal tube jobs that came with my last porch canopy - the holes as specified were too large and the bolt just rotated without any purchase - ended up stuffing out the hole with split bamboo!

 

[noseall]

The fact that you have now 'disguised' the location of the bricks v's the brick joints means that you are relying on pot luck to try and find a decent fixing. I would not be comfortable doing it unless the bracket connecting area was exposed.
You also need to realise that some walls are simply not suitable for point loaded fixings. Chemical anchors are a boon but also a big faff and require fixings into brick and not the joints.

 

[JimboMarimbo]

Very true...I'm going to have to chisel away a large enough area of rendering at each mounting point so that I can be certain of drilling into solid brick. Shame, as the rendering is sound and crack-free.

 

[endecotp]

Can't you drill some small test holes and judge where the mortar is by the colour of the dust and resistance to drilling?

 

[JimboMarimbo]

Hmm, that sounds like a much less invasive idea of the hammer-chisl-ing-off of the render - blind drilling small holes and checking the drill bit for mortar or brick dust; eventually a small scale 'map' of the area could be built up, and the proper 12/14mm drilling could commence, with confidence. Thanks, I'll go that way.