Black (breeze?) blocks at base of walls

[Saycheese5]

I've stripped some plaster to bare brick and noticed a few black blocks at the base of the brickwork on the inner leaf of the outside walls. They don't feel very strong (I can drill trough far easier than in bricks), so out of interest how can they be so strong as to support the weight of all the bricks above???

They look like breeze blocks but in black so cannot be made out of concrete (and are nowhere as firm). Just wondering what could they be made of?

In pic 01 I could not remove all plaster, pic 02 is from the chimney breast.

Many thanks!

Untitled

• Saycheese5
• 29 Jun 2013
• 1

Untitled

• Saycheese5
• 29 Jun 2013
• 1

 

[tony1851]

Probably cinder blocks or suchlike. Perfectly OK for supporting the house as the pressure on them will be relatively low.

 

[Nige F]

probably there so the chippies could cut nail the skirting on

 

[^woody^]

Breeze blocks are not made out of concrete

 

[Saycheese5]

They are so easy to chip away with a cold chisel when removing plaster, compared to bricks.

Perfectly OK for supporting the house as the pressure on them will be relatively low.

Sorry, I'm a bit confused. Which area(s) would there be high pressure?

 

[tony1851]

They are so easy to chip away with a cold chisel when removing plaster,

Modern aerated concrete blocks are also easy to chip away with a cold chisel.

What you seem to be worried about is the loadbearing capacity of the blocks. If you could actually work out the total weight of your house, from ground level to the top of the roof; and then work out the actual plan area of your walls at ground level, and divide the former by the latter, you will find that the load per square inch is very low. It could well be lower than the load per square inch under your shoes produced by your own body weight.

The load-bearing capacity of bricks and blocks is rarely a critical factor in domestic buildings. They can build houses out of bales of straw.

 

[Saycheese5]

The blocks look like coalite.

Thanks for your explanation. Interesting law of physics. Now I can see how those blocks do not carry as much weight as I thought when taking into account the load spread across per square inch.

 

[noseall]

They can build houses out of bales of straw.

One of the three little pigs tried that and look what happened to his house.

 

[^woody^]

Was that one of Tony's jobs? Probably had a 89x150 universal beam in it too.

 

[tony1851]

You crack me up - you reeeaaally do.

 

[^woody^]

Post a picture of those cracks Tony, we'll see if its structural or just a bit of shrinkage