flanagaj

I just want a second opinion on the below as the implications are significant and I'm struggling to understand the proposed wind posts locations and also the excessive amount of ladder reinforcement at 225mm centres. The internal block leaf is 7N medium density.

It's a shame, I cannot say that to building control.

I am trying to understand why you install bed joint reinforcement in the 2nd/3rd courses of brickwork above a window and door opening when you will have a lintel that is going to provide the lateral strength and stop the brickwork from bending inwards? Keen to understand why that thought process is obviously wrong.

I can see why they don't put mortar underneath. You have a continuous sheet of DPC which is 500mm wide on the horizontal and then it rises 225mm on the vertical before spanning the outer leaf. Plus it's all taped to the corners, so how you would physically lift it up to put mortar underneath it is beyond me.

Not sure if it's acceptable to do this, but our new builders have laid the blocks onto the Radon DPC with no mortar below the DPC and only mortar above the DPC. I did question this and they said it's fine. I even raised it with BCO and he said it was ok. Doesn't sound right to me, but I wonder if anyone has any experience of this approach. This xxxxxxx Radon membrane is the bane of my life and our neighbours said there isn't Radon here (BGS maps show 3%) The thought of having to demolish another bricklayers work is going to send me over the edge.

I have searched the internet, but haven't discovered how you terminate a cavity tray at a door opening and get a proper seal. As we have a DPC for Radon directly below the tray which spans the cavity, any water that gets through the tray between the cavity closer and the cavity tray will potentially cause damp. The image below shows how water getting under the cavity tray will have no where to go except towards the inner leaf.

So cut a long story short, I got back in touch with the original SE on this matter. Their response. Seems the current SE is over engineering. "on the basis of the plans in our structural calcs we do not consider that wind posts are required provided the ground floor constructed of blocks and timber stud walls are lined with plywood/OSB and tied to the masonry walls."

Given SE1 didn’t specify them, then surely the house should be built according to their calcs. If a problem manifests down the line, then they are ultimately responsible?

Some good points there Nick. SE2 has zero interest that I’ll have to get a breaker out to break up the blockwork and cavity fill to install the wind posts.

Good question. I have contacted the first SE to ask the question.

I am still waiting for the SE to give me the details. The bricklayers have said that it's no issue as they can start the build up elsewhere and come back to that section once it's finalised. It's frustrating that the original SE completely failed to spec them and the new SE specs them right at the last minute.

Wind loading on the brickwork. Just been speaking with the bricklayer and unless the wind posts can be bolted to the slab, I'll be getting a breaker in to break the blocks/lean cavity fill back to the foundations 😞

That is what I am pushing for. When she did the spec for the concrete slab, she specified 150mm slab laid on 50mm concrete blinding with two layers of A252 mesh. Given the ground here is no clay, very flinty soil and then chalk at 1200mm it was massively over engineered. Especially, considering it was a domestic slab.

So I am working to the drawings that were submitted to BC. To cut a long story short, I used Barrat Associates originally to do the SE calcs for the building regs submission. 3 months ago I got in touch with a local SE to do the design for the staircase and a bit later on, I asked her if she could do a full lintel schdule for me as the previous SE only detailed the large lintels. It was whilst she was doing this that she commented on the drawings not having any details regarding expansion joints. As a result I thought it would be a good idea to get her to have a detailed look at the drawings and see what else had not been specified/missed ...

So basically, I am completely screwed. The original SE made no mention of them. Building Control haven't made any comment on the submitted structural calcs and now I am near DPC and don't see how they can possibly be added at such a late date.