Building best practice - How high can one build?

[Ted]

I recently saw a house in the process of being constructed where an internal wall had been built out of 4" Thermalites.

This wall is almost 5m long and stretches across the property between the inner leaves which are also made of 4" Thermalites.

Either side of the internal wall in the exterior walls in close proximity to the internal wall are doorways and windows.

The internal wall also has a doorway in it with a Catnic lintol.

The wall is 2.75m high until it is restrained by some floor joists that create a first floor to one side of the internal wall.

It seems to me that this wall is rather slender considering its height and I would have built it using 6" blocks, particularly as it is so close to so many windows where it is tied to the inner leaf.

Does anyone know how to calculate what thickness of block should be used or know of any documents that would give this guidance?

[lutonlagerlout]

i think it depends if the joists are bearing on to the wall or not ted
we did a music room and the ceilings were 5 m high so we had to use 150mm blocks on the inside of the cavity,
however on normal domestics i have never seen anything more than 100mm blocks specified for internal walls,
i dont really like thermalites but they conform to building regs so thats that,but i always use aglites,lot better for plastering too
cheers LLL

[Ted]

Cheers LLL.

In this case the floor joists bear directly onto the wall.

[lutonlagerlout]

well the weight on the wall actually help stabilise it,but like i say i dont like thermalites m8
cheers LLL

[Ted]

It will stabilise it, I agree, but I still think a wider block would have been structually better in this instance as the inner leaf has so many openings close to this wall.

I guess only a structural engineer can give a definitive answer.