Blockwork types

[Vijay]

Am I right in saying there is basically 3 types of standard block:

 

Dense concrete block - used underground/rising/sleeper and load bearing walls

 

Lightweight/medium concrete block - used for non load bearing walls and beam and block flooring

 

Aerated (breeze?) - internal non load bearing walls

 

Is there another block that can be used internally for load bearing walls that aren't as heavy as dense concrete blocks?

 

Thanks

 

Vijay

 

 

[Construction Channel]

We build houses out of fibolites (probably spelt wrong), half the weight of concretes, possibly made by plasmor, again probably spelt wrong. But if you asked for either at a BM they should know what you are after. 

 

Edit: I was close 

http://www.huwsgray.co.uk/bricks/plasmor-fibolite-100mm-solid-block-7-3n-high-strength.html

[Vijay]

Looks perfect. I've emailed my BM's

[Barney12]

We're using dense concrete blocks for our external skin on the TF. Then traditional render with old fashioned paint. 

I'm now thinking the blocks are overkill as it obviously has no structural purpose. 

Another example of being talked into 'old Skool' building methods by the old boys. 

I guess though the "thermal mass" will be an advantage  

.....me runs  

Edited August 22, 2017 by Barney12
Typo

[PeterW]

1 hour ago, Barney12 said:

We're using dense concrete blocks for our external skin on the TF.....

 

Hows Steves back coping with those ..?? 

 

@Vijay the block density has nothing to do with its usage - it's the strength you need to look at. 

 

For example I can buy 3.5N, 7N and 10N blocks all in lightweight or aerated form, and yet they are a third of the weight of a concrete heavy. Aerated have a thermal impact, if it's all underground stuff or bearing walls then tbh I just use what is the cheapest 7N I can find ..!!

[Fallingditch]

9 hours ago, Vijay said:

Is there another block that can be used internally for load bearing walls that aren't as heavy as dense concrete blocks?

For example, YTong (which we built a 3 storey house out of), or Celcon, or Thermalite. (We went with YTong because the others couldn't quite meet our inner skin specification.)

[Barney12]

8 hours ago, PeterW said:

 

Hows Steves back coping with those ..?? 

 

 

Im not sure he's overly impressed by my choice of blocks  

[Vijay]

Is there any noticeable difference on soundproofing/deadening between the different blocks when used for internal walls?

 

I've attached a basic sketch of the internal walls I need to build. The yellow are sleeper walls to support the B&B floor which I've been told I can do in 100mm blockwork apart from where 2 beams meet where it needs to be a 200mm wall (so I was just going to double up the block on those points). The red are internal load bearing walls which go up 2 floors.

 

I'm going to use concrete blocks for the internal rising and sleep walls. I need to build up to between 270 and 300mm so how do I do that with standard sized blocks? I assume I'd have to cut the blocks?

[bassanclan]

You want some concrete coursing bricks. They are the same size as bricks, but made of the same material as your concrete blocks.

 

Alternatively use engineering bricks, which are generally a bit cheaper.

 

10mm mortar

block laid flat

10mm mortar

block laid flat

10mm mortar

65mm brick

= 285mm with no cutting

 

 

[Vijay]

Thank you   

 

So can I just increase/decrease the mortar joint depending what I need? (between 270 and 300mm)

 

Is there any other way of doing this in single skin/block upright (as it's less blocks for me to lay) or would that involve cutting blocks?

 

I have a Stihl cut off saw if I need to cut blocks

 

 

Edited August 23, 2017 by Vijay

[PeterW]

For the sleeper walls just lay them on the flat. Easier and quicker than cutting 

 

As @bassanclan says, concrete commons will help you build the levels up too at 65mm depth. 

[Vijay]

Worked out I've got just over 40m of sleeper/internal rising walls which is approx 94 blocks. Do you think it would be quicker to lay 188 blocks and 188 bricks or 94 blocks (upright) and a course (188) of engineering/coursing bricks which would give me 300mm and cut down and blocks where I need to?

[Vijay]

22 hours ago, PeterW said:

 

Hows Steves back coping with those ..?? 

 

@Vijay the block density has nothing to do with its usage - it's the strength you need to look at. 

 

For example I can buy 3.5N, 7N and 10N blocks all in lightweight or aerated form, and yet they are a third of the weight of a concrete heavy. Aerated have a thermal impact, if it's all underground stuff or bearing walls then tbh I just use what is the cheapest 7N I can find ..!!

 

So where would you use a solid concrete block and where would you use a lightweight concrete block - both 7n? What's the point of the heavier solid block when the lightweight will do? is it just cos it's slightly cheaper??

[bassanclan]

10mm mortar

215 block

10mm mortar

65mm brick

=310mm which is too thick

 

You mentioned doubling up to 200mm thick walls, laying blocks flat solves that problem.

 

I personally would not use aerated blocks underground, nor if a wall was being rendered. I don't much like them for fitting kitchen wall cupboards to, but they are ok.

 

Lightweight obviously have better insulation properties than denser blocks

[Declan52]

Think you need to get your calculator out again.

1 10mm bed 

1 215mm block

1 10mm bed

1 65mm brick

 

300mm.

 

You use a standard block if price is an issue, they are the cheapest and the thermal properties don't matter. 

You use thermal / lightweight/ aerated if you want to boost the u value of the wall you are building or to provide a thermal break as you come out of the ground.

I used aerated blocks on all my inside skin of my cavity build but every single internal wall was just a standard block.

You won't need to use anything stronger than 7n blocks.

[Vijay]

Yeah in some places I need to have a 200mm wall but it doesn't make sense to build a 9m long wall at 200mm wide where I only need 200mm in a few places - so the idea is to build the whole wall at 100mm wide and double it only where I need it, as it's only to support a floor beam.

 

Thanks Declan

46 minutes ago, bassanclan said:

 

 

You mentioned doubling up to 200mm thick walls, laying blocks flat solves that problem.

 

 

 

Yeah in some places I need to have a 200mm wall but it doesn't make sense to build a 9m long wall at 200mm wide where I only need 200mm in a few places - so the idea is to build the whole wall at 100mm wide and double it only where I need it, as it's only to support a floor beam.

 

Thanks Declan. Plan is to use a Thermomax board for the thermal break and then I'll carry in in lighter 7n block