Using division to calculate the number of bricks needed

Speaker 1: Right then, Dan. What we've got is this stretch of garage brickwork wall here we need to build up today.

It's 4.8 metres in length and we're going to be using Flemish brickwork bond for this particular set of brickwork.

I've done you a drawing here of a Flemish setting out and what you'll need to do is work out how many bricks you get into the 4.8m length of wall.

Speaker 2: OK, no problem. Thank you.

Speaker 1: Brilliant, thank you Dan. Cheers.

Speaker 2: (TO AUDIENCE) So I need to build this 4.8m length of garage wall in Flemish bond which entails using more bricks than in your standard stretcher bond but less bricks than your English garden wall bond.

So I need to work out the brick sizes and then calculate how many bricks I'm going to need.

Speaker: So I need to work out the amount of bricks that will go into this 4.8m length of wall.

To do that I need to know the pattern, which is Flemish bond and the brick sizes so I can calculate exactly what I'm going to need.

OK so the standard size of a brick is 215mm in length 100mm across the header and 65mm thick.

I know I'm having to build this wall in Flemish bond so the pattern for Flemish bond is stretcher, header, stretcher, header, is the pattern.

I need to take into account 10mm mortar joints.

Therefore, stretcher, header and the two 10mm mortar joints either side of the header which will be 335mm.

Therefore, I need to work out for my 4.8m wall how many times 335mm goes into 4.8m.

So we know that the length of our wall is 4.8m.

We work, in brickwork, in millimeters therefore we need to convert this.

4.8 times 1000 equals 4800 millimeters.

4800mm divided by the 335mm we worked out was the size of our pattern, which we know and established earlier was 335mm…

…equals just over 14 patterns. So we know that 15 stretchers and 15 headers will be enough to fill the length of the wall.

Speaker 1: (TO AUDIENCE) So we know that the standard length of a brick is 215mm.

Sometimes, however, this varies. Like this one, for example, is only 211mm and therefore already 4mm undersize.

So even though we've calculated the amount of bricks we're going to need in our wall there is still a variation in brick sizes.

So we need to make little adjustments in the mortar joints, so that the brick bond works.

So to do that I'm going to dry bond the wall out first.

Speaker 2: (TO OTHER PEOPLE) How are you getting on then, Dan?

Speaker 1: Yeah, absolutely fine mate.

I've just dry bonded out the course.

Speaker 2: That's brilliant. So how did you get to this stage?

Speaker 1: Well we took our 4.8m length and we had to work out how many times our 335mm pattern went into that.

Speaker 2: OK, that's brilliant. It looks really good. Did you have any problems?

Speaker 1: No, not really mate, no problems.

Just that some of the bricks are slightly undersized so we've had to widen the size of the mortar joints a little bit just to incorporate that, so it still looks alright.

Speaker 2: That's brilliant. I see you've had to incorporate a smaller brick on the end there.

Why have you had to do that?

Speaker 1: Yeah, so what it is, over 4.8m 335mm won't go perfectly.

We've had to end up with a closure at the end to get over that discrepancy.

Speaker 2: That's brilliant. It looks really good, Dan. Well done.