Exterior wall built with concrete and bricks

sufiwho

Dear all

I am planning an extension. The existing building is red bricks, and I would like the extension built with appearance in some way echoing it.

I am thinking it might be a good idea to have the outer wall built with concrete blocks (and then rendered) and bricks (maybe at the base and surround the door and window for echoing detailing).

My question is: Would there be issues/difficulties if this wall is made of different materials, such as different levels of stress etc..?

Or is it better to use bricks/slips for partly cladding?

Many thanks!!!

phill99

No. But it will certainly add to the cost.

Doozergirl

Why don't you just match the bricks?

EachPenny

sufiwho wrote: »

My question is: Would there be issues/difficulties if this wall is made of different materials, such as different levels of stress etc..?

If you take a strictly theoretical approach then yes, different materials (e.g. blocks/bricks) have different properties such as thermal resistance, coefficients of thermal expansion, Young's modulus etc.

But for something on the scale of a house extension most of the differences have no significant impact. The one you do need to keep an eye on though is differences in thermal resistance, as this could lead to cold spots on the walls.

Furts

You may be jumping the gun with your wall choices. You will be governed by what the Planners will allow.

If you are not subject to Planning constraints then a fundamental is concrete blocks are not good news when used on the outside of a home. However if you are thinking of a small extension, typically single storey then fine, everybody does would say do it.

You are trying to complicate what is a simple process. Fine if done with care by the bricklayers - you have to offset the brickwork to allow for the render, starting down at the foundations.

Modern renders like K Rend are fine, but if you are thinking of sand cement render on block walls then this is bad news.

Mistral001

Old stone buildings often had window and door openings finished with brickwork, so what the OP is proposing is not uncommon. The type of brick probably needs careful consideration. It should be a brick that is suitable for exterior use and have moderate frost resistance.

Furts

Mistral001 wrote: »

Old stone buildings often had window and door openings finished with brickwork, so what the OP is proposing is not uncommon. The type of brick probably needs careful consideration. It should be a brick that is suitable for exterior use and have moderate frost resistance.

Old stone buildings were like this for a good reason - they could not be built without doing this. In essence here the brickwork provides the true, square, plumb opening for the window to fit in. This opening could not be achieved with random pieces of stone that are used in the walls.

One problem OP has to accept is concrete blocks are vastly different to bricks in terms of expansion/contraction/shrinkage. That is why one bricks and blocks should not be built into the same wall. Does not stop bad builders doing this though - take a look at some house extensions and it becomes apparent!

tony6403

Mistral001 wrote: »

type of brick probably needs careful consideration. It should be a brick that is suitable for exterior use and have moderate frost resistance.

Interested to know which bricks are not suitable for exterior use.

Furts wrote: »

Old stone buildings were like this for a good reason - they could not be built without doing this. In essence here the brickwork provides the true, square, plumb opening for the window to fit in. This opening could not be achieved with random pieces of stone that are used in the walls.

Seems to have been done with these
https://www.pinterest.co.uk/pin/291678513336273515/

http://www.alamy.com/stock-photo-traditional-stone-buildings-in-the-pretty-northamptonshire-village-84557831.html

https://www.pinterest.co.uk/pin/534661786982403498/

Furts

tony6403 wrote: »

Interested to know which bricks are not suitable for exterior use.


Seems to have been done with these
https://www.pinterest.co.uk/pin/291678513336273515/

http://www.alamy.com/stock-photo-traditional-stone-buildings-in-the-pretty-northamptonshire-village-84557831.html

https://www.pinterest.co.uk/pin/534661786982403498/

Hanson bricks, also known as LBC, or Flettons are useless for exterior work on exposed chimnies, garden walls, retaining walls and the like. Couple this with wet and frosty locations. Similarly if one is pragmatic concrete bricks should be avoided for external walls.

Your pinterest shots do not reflect an understand of building. Cost, availability and practicality comes into matters. Some stone will not dress, other stone is random rubble, other stone is expensive to dress relative to using bricks, other locations have no bricks available because there is no nearby clay, other locations have checked reveals so the brickwork is hidden ... just to give some examples.