Brickie

Ignore the lintol shown-typical installation is more like this. A cavity tray is usually installed around the perimeter at around 150mm above ground level,this is a pretty standard detail now.

A cavity tray isn’t really installed as per the drawing-it would come out across the top of a PIR sheet & then down to the outer leaf. Some people chamfer that sheet below to ensure a fall away from the inner leaf,which isn’t great thermally but probably preferable to any moisture finding itself trapped on a minute rise in the DPC tray. All the more reason why I don’t believe PIR is a suitable insulation material for masonry builds.

Is there a steel ridge beam?

I’d suggest a 1:1:6 mix is about right for aerated. In summer months,I ideally like to wet the top of the course below before bedding out,to kill the initial suction grab much the same way as old school plasterers would.

That cabling & the timber either side are going to give you a headache. How come the builder’s not installing the pad stone?

My understanding is that bonding shouldn’t be used on an exterior wall but @nod is the person to ask.

Is it not hanging tiles on the bays?

Possibly you’re thinking of Tuck Pointed brickwork-a fairly common practice at one time to give the illusion of very accurate,thin jointed work.

+1 Treat the movement joint as you would a door or window reveal with the ties in to the frame @225 vertical spacing both sides of the mj.

I have a mate who carries out basement digs on this basis at times,and I believe the percentage is tiered as an incentive to keep costs down (I.e. 15% to £150,000 dropping to 10% thereafter,just as an example.) At first glance it might not seem like much of a carrot but bear in mind that if he ‘milks’ the job & breaks the threshold then,come the end of the job,he’s still tying up all the annoying loose ends,but earning a far smaller commission for his trouble.

You should be fine to remove the infill beneath the arch. Going forward,the chimney stack will need ventilating with an air brick,top & bottom.

+1 to that.

Make sure you get absolutely spot on dimensions from the window company. Not done a TF myself for years but we used to have to leave a gap top & bottom around the frames to allow for differential settlement between the TF & masonry-worth checking what’s required now as the bricklayer will need that info too.

I was taught that the mix should get weaker from first to second coat or it’ll pull- @nod?

I’d think you’d want a decent scaled drawing. Might not be the thing to attempt early on.