Early morning sun: the concrete pour part way through

Pouring the slab

Andrew Kerrby author page

Construction

Saturday June 20

D Day

The two weeks leading up to this morning had caused some very stressful moments: uncertainty due to bad weather coupled with hasty arrangements for gravel deliveries and finding a bricklayer last minute. But the day had finally arrived to pour the concrete slab of 60k House – just 3 days before the deadline for the First Home Builders Grant (I’ll talk more about this soon in Finance ). And wasn’t it a glorious day.

 

Early start: stuck behind the first concrete truck while driving to site before sunrise

Early start: stuck behind the first concrete truck while driving to site before sunrise

 

After getting stuck behind the first concrete truck it was all go when we arrived on site. This was around 7am, two days before the winter solstice (sunrise wasn’t until 7:40) – concreters don’t get much beauty sleep.

 

More trucks: pumping the concrete to the slab via a pump truck

More trucks: pumping the concrete to the slab via a pump truck

 

Messy work: gumboots are a must

Messy work: gumboots are a must

Pump. Vibrate. Screed. Repeat

A pump truck was again used as a relay to pump the concrete from the concrete truck to where it was needed. A concrete vibrator is used to settle and compact the concrete, ensuring the concrete is spread evenly around all obstacles (especially important for the steel reinforcing in the footings) and eliminating any air bubbles. The concrete is then leveled by a screed (long straight edge) with the excess concrete being scraped away with a shovel.

 

Teamwork: Stuart screeds the concrete while Greg removes the excess

Teamwork: Stuart screeds the concrete while Greg removes the excess

 

Pumping, leveling and vibrating the concrete

Pumping, leveling and vibrating the concrete

Like watching paint dry

Concrete is a natural product. By that I mean it is unique. There are many factors that will determine how quickly concrete will ‘go off’ (set): water content of the concrete; air temperature; humidity; if any accelerator or retardant has been added to the mix; etc. It was a sunny day but it was the middle of winter in Tasmania so the weather never got very warm. That meant we (Stuart the concrete finisher and myself – the concrete trucks and pump were long gone) had to wait around, all day in fact, before the concrete had set enough to walk on. The fall to the floor waste for the shower in the wet area was done by hand with a trowel; the rest of the slab (which will be the finished floor) was finished using a ‘helicopter’ – a mechanical tool that has multiple trowels and spins slowly, smoothing and leveling the slab as it moves across the surface. Very cool tool.

 

 

Hands and knees: Stuart working by hand to make the fall to the floor waste (shower) in the wet area

Hands and knees: Stuart working by hand to make the fall to the floor waste (shower) in the wet area

 

Flying solo: Stuart pilots the 'helicopter' - a mechanical tool for finishing concrete slabs

Flying solo: Stuart pilots the ‘helicopter’ – a mechanical tool for finishing concrete slabs

Relief!

It may not look like much – just 61 square metres of concrete slab – but the sight of the slab poured and nearly finished was such a relief. This represented substantial commencement by the terms of the grant guidelines – with three days to spare. Greg and all of the contractors had worked tirelessly through some challenging conditions in order to meet this important deadline. Just 10 days earlier there was a patch of dirt – now there was the base of a building. They say getting out of the ground is the most difficult stage in any building project – I don’t doubt that. Now the rest of the build could be fun.

 

Mind the step: the setdown in the slab for the wet area

Mind the step: the setdown in the slab for the wet area

 

A thing of beauty: the slab, poured and nearly finished

A thing of beauty: the slab, poured and nearly finished

 

Costs: concrete – $2,211; pump – $847; concrete finisher – $500
Total cost of building to this stage: $20,992 including materials and labour

 

Disclaimer: Any advice contained within this blog is of a general nature only and cannot be relied upon. Details provided are in good faith and relate specifically to this project. Any author will not be held responsible for advice or information presented.