Part of Application of number (Levels 1 and 2)Construction
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Speaker 1: OK, Harry, this is what we're doing today.
We're measuring out and marking out these wall plates. We're working out how many trusses we need up here.
Speaker 2: OK.
Speaker 1: For the length of wall plate.
Speaker 2: Yeah.
Speaker 1: At 600 centres.
Speaker 1: On this plan the building is 5.3 metres long.
We need to work allow for the chimney coming in 400 millimetres from one end.
Speaker 1: The first job though is to work out exactly how many trusses we need to lift up.
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Speaker: So I've been asked to set out the trusses on the wall plate and I'm going to do a diagram to help me work out how many I need.
I'll draw it to scale, so one of these small squares on the graph paper for each 100mm.
So I know that my wall plate is 5300mm long.
I then have my chimney, which is 400mm from the wall plate, so that's four small squares and then I can set out my 600mm for my trusses from that point.
So the first one comes down at 600mm so that's 6 small squares.
So they're my trusses along the wall plate and I've got a little bit in here, which I would in-fill.
So that's another one there. That makes 1, 2, 3, 4, 5, 6, 7, 8, 9 trusses, plus the one in-fill, which is another truss, altogether making 10 trusses, overall.
Speaker 1: (TO AUDIENCE) So I've been asked to set out these roof trusses today, on this wall plate.
The chimney works out to be about 400mm off this internal wall.
After I've marked that, my 600mm start in multiples of 6, 12 and 18 until I reach the end, which works out at 10 trusses.
Speaker 2: (TO OTHER PEOPLE) OK Harry?
Speaker 1: Yeah.
Speaker 2: How's it going?
Speaker 1: Yeah, good.
Speaker 2: So you set out along from that end?
You've come 400 for the chimney?
Speaker 1: Worked my 600s down.
Speaker 2: And the trusses are set out at 600 centres?
Speaker 2: OK, just double-check everything, but looks like a good job. Well done.
Speaker 1: Okay, cool.
Speaker 2: Thank you.
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