Plaster on brick

With the description of the work I would remove the plaster 100% depending on the size of the gap around the door either plasterboard or undercoat plaster (bonding) then top with muiltfinish with a nice blend so left flat and smooth ready to be painted

This is alarming and the plasterer if you can call him that has no clue what he is doing…. A pva sealer should of been applied to the brick followed by a bonding plaster direct to brick up to frame and existing plaster leaving 3 mm for finishing plaster to be applied on top to trowel into existing leaving a seamless finish

Yes I would definitely remove the plaster, as there was no correct preparation to the walls, and this will just cause it to crack and eventually crumble away.

This would depend on what the surface is, if the substrate isn’t too bad you can bond over it with a coat of pva . If not yes plaster board would be more sufficient

A bonding agent is preferable before plaster application and the recommended plaster for brick surface would be thistle hardwall renovating plaster and finished with multi finish.

It’s cracking because the plaster was put straight onto bare brick without any bonding or backing coat. The right way is to remove the loose plaster, apply a bonding coat or hardwall first (or fix plasterboard if you prefer a quicker option), and then skim over that. That’ll give you a proper key and stop the cracking from happening again

The answer to this question depends on the age of the property and the type of plaster used? If you have a period property (no cavity) no bonding agent would be used and a breathable plaster should be applied to a moist substrate. If you have a cavity there’s multiple ways to apply plaster to the walls but it should done in layers with proper substrate preparation. Bonding plaster isn’t designed to be used on high suction backgrounds so it would have to be sealed with a bonding agent first prior to using it. The best option in my opinion for bare brick if wet plastering is HardWall. A three coat system, Scratch coat at 10mm, Float coat at 10mm, Topcoat using MultiFinish at 4mm Of course the walls can also be dry-lined with plasterboard with battens or drywall adhesive depending on suitability. If a period property you can use wood-wool or fibre board to line the walls prior to a limestone based plaster for best results. .. If your walls are cracking, boss or look uneven or even if your unhappy with the service provided you should contact the plasterer and inform them that you expect it to be rectified.

No bonding agent is needed as long as you damp the brickwork forst