bricklaying - using a string line

[sm_jamieson]

Doing my first bricklaying where the finish will matter - the brickwork for my extension. Currently just up to ground level, so I've had some practicing space ! Stretch was 5 metres. Using a string line pulled very taught over the distance, still seemed to dip a few millimetres in the middle. I also used a spirit level and the level seemed to be fighting with the string ! I didn't want to support in the middle, since the string could catch and compromise the straightness. But its a pain keep using the spirit level to make sure you are not dipping in the middle. Having said all that its looking perfectly acceptable so far ! Very slow though.

How far should you use a string without supporting it in the middle ? Any other tips about laying to a string line ?

Thanks, Simon.

[George]

I've only ever tried my hand at building a wall once and it was or didn't look straight,so I knocked it down what I had started then before I rebuilt it I thought about an idea. Bit slow but the results were perfect,I got some wood about 1m long and screw it together to for a trough shape,this trough shaped sides were the width of the bricks I was using and I cemented in the bricks first layer and placed this trough over the bricks and tapped the trough along the first course to make sure they were all straight...it worked a treat. I left the first layer to set before carrying on and used the same teqnique till I buit the wall. ;-) Unorthodox medthod but it worked for me.

[George]

Take a loo at the 'bricky' tool in the poor video. Maybe you could make a wooden one ;-)

[tonyjeffs]

I'm about as inexperienced as you. I've done a couple of small projects that look ok (and one recent one that looks awful - an off day!) You could do it in 3 x 1.6m stages, but then you would have to keep stopping to change the string. Perhaps it's an optical illusion, or not saggging as much as it looks. When youve completed a 5m course, get a couple of people at either end to make sure the string is taught, and see if your run is level or really has a dip. I'd also use a long piece of timber to mak sure no bricks are standing proud or low, and I'd allow myself a tolerance of 2mm because that's the best I can manage. You could weight one end of the string to keep it taught.

Tony

[Andrew Mawson]

I've recently had to build some cement blockwork walls 9M long that had to be dead 'nuts on' level, and I used a string for striaigtness and my rotating laser level for height - worked a treat and actually no slower once the tripod is set up.

AWEM

[nightjar]

That is because the level is for levelling and the string is for straightness. The reason you don't level with the string is that it sags in the middle.

Try googling tingle plates.

Colin Bignell

[sm_jamieson]

Trouble is, if you care about the actual coursing, you still really need to use a string line. I think if you just relied on the mortar bed, errors would compound as you went up. Mind you, the home office build in the video looks very simple, and magically, eveything fitted. I think the guy (the inventor) is an "expert" in using his tool (fnarrr).

Also, unless you want a raked finish, you need to point everything afterwards. The info makes a point of a raked finish, and I've noted this finish is getting more common on offices, supermarkets etc. Bit would look a bit weird on my extension - I really need a bucket handle finish.

This looks a bit wacky but interesting:

[sm_jamieson]

The dip isn't really noticeable to the eye, only slight and not really a problem, but when you are laying bricks to the line it is a bit un- nerving.

Simon.

[sm_jamieson]

I like it. And easy enough to make. Good thing is, it will slide across the brick supporting it and still allow the line to centre horizontally. Simon.

[George]

Bucket handle finish? you a half round? easy use a wooden dowl and slide along the course once or twice.

[sm_jamieson]

Yep its easy to do with normal laying, but the bricky tool leaves the mortar recessed, to you have to add loads of mortar when pointing up. Which is why I might not end up using my bricky tool, useful though it can be. Simon.

[Rick Hughes]

Normal practice is to set up gauge or build up quoins or corners at either end.

Then run string between .. , if too long and 4m would be about my limit, then lay an intermediate brick plumb it in with storey rod (or measure up form DPC to get horizontal correct, and put a 'tingle' in place on the line. These can be a thin piece of metal with 2 vertical slots - you feed line between slots.

Place a brick on top and that then stop nay intermediate sag in line.

The alternative, is simply take a piece of cement bag, fold it over line and lay this on top of your plumbed intermediate brick, and place another brick on top to keep it there.

Remember key thing when using a line, brick arris must NOT be touching the line, good guide is thickness of trowel between line & brick edge. If it touches.. it will put line out ... multiply by many bricks, and that is how so many long walls have bows in them.

If you want a really good guide on brickwork ... get hold of:

[sm_jamieson]

no to let it touch. Can you purchase a tingle plate ? Cheers, Simon.

[Phil L]

Can't se the OP so I'll have to reply to this.

It's across the brickwork that you have to watch and this is where a boat level comes in handy, that is, to check each brick from front to back so that they are not leaning forwards or backwards as this will cause untold problems higher up if ignored. IE, you may get all the top edges of the bricks touching the line all the way along, but they still may be sloped, meaning that your next course will be even more sloped until you are getting virtually no mortar at all under the back of the brick and the front of the course will have a thick bed.(or vive verca)

Just make sure your corners are completely upright in all directions and perfectly flat too, then use the string as taught as you can get it without it snapping.

You don't need a level except for the corners, rely on the string, and don't worry about millimetres, from personal experience, I can safely say that

*all* brickwork, even that laid nby a master bricky is imperfect if you look at just one or two courses, but the overall effect is usually very neat.

[Rob Horton]

Why not wait until the moon is directly overhead. It's gravitational pull should reduce the amount of sag to acceptable limits. Works for the sea.

;)