Building a new brick wall

[renishawphil]

I currently have a large garden boundary which currently has a low wall (in sections) with fence panels above.
I intend to replace this with a solid wall.

First of of all how do i assess if i can re use the original foundations or not? (i have not checked out the foundations at all yet). I was told i could simply re use the existing block work and build on top of the block work with bricks,but i am not very happy doing that (in some places the block work is three blocks high and not complete(ie gaps in the wall for posts)

The wall is going to be double skin.
Would i be better to do a double skin brick wall or should i go for a brick faced wall with a block back (using wall ties)

I am just going through ideas at the moment and may in the end get someone to do it,

What else should i be consider. (small parts of the wall at the moment are currently supporting (earth in some places and patio in another)

 

[Doggit]

You first need to do an exploratory dig, and check the depths of the foundations. Assuming they're between 375 to 450mm, then you can go for a single skin with supporting piers every 6ft, or a double skin wall, but not a brick and block type.

 

[CambridgeBrummie]

There is some great advise in the BRE Good Building Guides GBG 14 and GBG 19.

 

[renishawphil]

You first need to do an exploratory dig, and check the depths of the foundations. Assuming they're between 375 to 450mm, then you can go for a single skin with supporting piers every 6ft, or a double skin wall, but not a brick and block type.

Thanks,is the a reason i couldnt go for brick and block type?, is this due to weight?

 

[^woody^]

but not a brick and block type.

Why not?

 

[Doggit]

Partially, the concrete blocks are going to be heavier than bricks, so you'll need deeper foundations, and you'll then need to render the blocks afterwards. The blocks will be cheaper than bricks, but by the time you've rendered the blocks, and with the additional time required, you'll lose any savings you've made.

And a wall made from bricks both sides will look nicer - but it's personal preference of course.

 

[^woody^]

concrete blocks are going to be heavier than bricks, so you'll need deeper foundations,

Lol. That's a bizarre statement.

 

[Doggit]

A brick is 3" wide, and a concrete block 4". Okay, I may have made an assumption on the density of the concrete block, but it is outside, so he won't be using theremalites - or was he intending to

 

[Doggit]

Sorry Woody, dead brain tonight they're both the same width, and fairly the same weight, but I still think the brick walls a better idea

 

[^woody^]

Foundations do not carry weight, they transfer loads to the ground. So for low rise walls/buildings the weight of wall does not matter and the depth of the foundation will be the same whatever the wall.

 

[Doggit]

Inherently true, but as you can't guarantee the same stability of ground across a wide distance, you have to have a relationship between the height of the wall (and therefore it's increased wight), and the depth of the foundations.

 

[^woody^]

It's a garden wall not the Hoover Dam remember

 

[renishawphil]

Thanks guys for your replies (and girls)
We have decided to get a builder to do the actually brickwork (we will get materials as we work for a company which owns a large builders merchants so get good rates.

We will however do our own foundations, due to cost we are going to go for a brick and block wall, the back of the Wall backs onto a footpath and a field so we won't really see it, so makes sense.

What blocks (size,type etc) should be used for this wall? (Most of the wall won't be a supporting wall). Also how should we work out the depth of the founations, wall will be around 6ft high and some of it on a slope.

 

[Doggit]

If it was flat ground, then medium density blocks, or foundation blocks should be fine, but the lightweight aereated blocks will absorb water. You're foundations would be 3 times the width of the wall, so 600mm, and about 400mm or so deep.

But you haven't mentioned which way the slope is going; is it in the direction of the wall, or will the wall go across the slope, in which case, I'd let the builder do the foundations as well.

 

[renishawphil]

Thanks . Its going with the slope