Blockwork on party walls

mustela

Hi all,

Observing traditional house building around Dublin I have noticed blockwork for party walls seems to be different.

Some seem to be a double row of block on flat, which to my understanding keeps them within traditional coursing measurements (225 mm) but others seem to be a single row of blocks on flat.

Is there a reason for this would anyone know? Or is something like this entirely at the discretion of the blocklayers?

muffler

Blocks on the flat are 225mm. Im not sure what you mean by 2 blocks on their flat measuring the same.

Mellor

https://www.boards.ie/discussion/2058368915/blockwork-on-party-walls

I'm not sure what you mean by single row vrs double row. Do you mean courses?
The way block on flat are laid in courses doesn't change the height of coursing.

housetypeb

Block on flat. The difference is that the bond is staggered for half bond every 2nd course rather than after every 2 courses. The height remains the same. Think regulations now say that's the correct way now for party walls?

mustela

https://www.boards.ie/discussion/comment/122613710#Comment_122613710

2 courses of blocks are 225mm

mustela

https://www.boards.ie/discussion/comment/122614105#Comment_122614105

Yeah that’s a better way of putting it. In some party walls I see, it still is every 2nd course that blocks are half bond, where other party walls it’s every course.

Any one any idea why? Where would this be mentioned in the regs? Could anyone point me in the right direction.

Mellor

https://www.boards.ie/discussion/comment/122614201#Comment_122614201

The height is the same whether that are stacked or staggered.
a block on edge is also 225 per course

muffler

https://www.boards.ie/discussion/comment/122614201#Comment_122614201

You are talking about height so. Pity you didn't mention that before now.

mustela

I’m aware of block work coursing gauges.

I’m curious as to why some party walls are built in a double block on flat opposed to a single course of blocks on flat.

In the first picture, there is a double course of blocks per course. In the second picture there is a single row per course. In house construction, why are some jack / party walls built with a double course (Pic A) and some built in a single course (Pic B)

Mellor

https://www.boards.ie/discussion/comment/122615549#Comment_122615549

Neither will affect the course height

Penn

They're meant to be staggered in each course now as part of the sound regulations (Part E 2014 Diagram 4).

Gumbo

Double course is against building regs. Specifically Part E. It’s states it’s not to be done.

If spotted, it will be asked to be removed by Building Control or a good Certifier should be inspecting before it gets too far.

Diagram 4 onwards.

mickdw

https://www.boards.ie/discussion/comment/122615549#Comment_122615549

In my opinion, the top photo is the more correct for the simple reason that it allows tie in of a block on edge for any perpendicular walls without chopping and cutting.

Not so much an issue with party wall but for typical blockwork I would always expect to see the 2 blocks directly stacked to create a 225 high bonding course.

Edit- was not aware of the requirement for single coursing in part E. Noted for future ref.

standardg60

https://www.boards.ie/discussion/comment/122615549#Comment_122615549

Just to add to the fun in your 2nd pic the wall to the right of the ope is also double course.

crashpilot

Horses for courses 😎

mustela

https://www.boards.ie/discussion/comment/122615897#Comment_122615897

https://www.boards.ie/discussion/comment/122615901#Comment_122615901

Thanks both for the info and sorry for any confusion. Pictures are the way forward 😂