# laying concrete blocks



## sisyphus (Jul 14, 2012)

Hello all, I would like to learn how to lay concrete blocks but have never done this. I've watch a few videos on this, but I can't figure out how they keep the joint spacing uniform. does anyone have any tips for a newbie? thanks.


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## stuart45 (Jul 14, 2012)

Do you mean the bed or perp joints, or both?


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## sisyphus (Jul 15, 2012)

I'm not famuliar with the term perp joint. I'm refering to the spacing between the blocks on all sides. how are the spacings kept uniformed?


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## stuart45 (Jul 16, 2012)

In the USA brick and block spacing rules can be used, but here we use a piece of 2x1 batten with the course marks on it. For example if the height of the block is 8 5/8 inches with a 3/8 inch bed joint you mark the batten every 9 inches and when building the corners check the heights with this. If you need to lose an inch overall in height you take a bit off each course so the marks are a bit lower, or increase them if you need to gain an inch.
With the perp or head joints (vertical joints) you set out the first course, and make them smaller or bigger to suit the run. Then next course lay the block or brick so it's halfway over the one below.
For high quality brickwork a pencil mark is made about every 4th brick using a level to keep them plumb.


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## sisyphus (Jul 16, 2012)

thanks for the reply. know anything about installing concrete steps? specifically about whether they need to be attached to the house or not?


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## kok328 (Jul 16, 2012)

Pre-formed concrete steps do not have to be attached to the house.


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## stuart45 (Jul 17, 2012)

Steps don't have to be attached to the house. Here's a brick set that have a gap as they would bridge the damp proof course if touching the wall.


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## sisyphus (Jul 18, 2012)

stuart45 said:


> Steps don't have to be attached to the house. Here's a brick set that have a gap as they would bridge the damp proof course if touching the wall.
> View attachment 4112


that might be doable for me. I'm assuming that the bricks are sitting on a concrete slab? and it look's like that's attached to the house? and what would you do to conceal that gap?


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## nealtw (Jul 19, 2012)

Never herd of (damp proof coarse) before, but I don't work on brick or block so I shouldn't be surprized. It makes alot of sence to keep thing away and allow things to have air. Is this used in North America?


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## stuart45 (Jul 19, 2012)

sisyphus said:


> that might be doable for me. I'm assuming that the bricks are sitting on a concrete slab? and it look's like that's attached to the house? and what would you do to conceal that gap?


They are on a concrete slab. The foundation depth depends on ground conditions and your climate. The slab just butts up against the wall. The exterior 
wall will have stucco down to the batten, which is just above the damp proof course. 
nealtw,
 You may know damp proof course by a different name. Nowadays it's a plastic membrane that comes in a roll the width of the brickwork which is laid on top of the walls at least 6 inches above the ground to prevent rising damp.
Years ago 2 courses of slate were used.


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## nealtw (Jul 19, 2012)

Stuart: Like I said I don't work on brick. We do concrete foundations on a footing and there is no expectation of have one stick to the other so we put a groove in the footing for foundation to bite into and the we add rebar too. Just wondered why we don't put a membrain there too. We put vapour barrier under the slab and outside the foundation and still allow wicking in the wall.


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## stuart45 (Jul 19, 2012)

Here's a photo of the DPC on the external skin of a brick/block cavity wall. 
A DPC of some kind has been required on house walls here since the Public Health Act in 1875.


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## nealtw (Jul 19, 2012)

So it's relatively new then.  Learned something today! Thanks


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## BridgeMan (Jul 23, 2012)

stuart45:  Is my eye-sight that bad, or are there no weep holes in the bottom of that brick work?


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## stuart45 (Jul 25, 2012)

BridgeMan said:


> stuart45:  Is my eye-sight that bad, or are there no weep holes in the bottom of that brick work?


There does not like there is any. If the inner wall is blockwork the builders don't usually put them in, although the original designs for cavity walls had them. 
When then inner wall is timber, as is a common type of build in the USA, weep holes are always put in at DPC level, or just below.


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