Laying a driveway

[SiW]

Hi all, Am new to the forum although have been a regular visitor. I am going to lay a drive way soon and want to know correct procedure and materials. I have done some brickwork before but am not a builder!! I am just making a hard standing so basically forming a slab. Do i need a DPM to go on sand ontop of the hardcore?? Or can i put the concrete on top of the hardcore?? The drive is not near the house. Also the area is about 5x5 metres so i dont know about expansion joints. How do i form these?? and drainage was thinking of a soak away??

Sorry for the questions

Thanks in advance

 

[^woody^]

Take out the soft soil - this may be anything up to 250mm

Generally lay a minimum of 100mm of hardcore, compact it well with a plate compactor (Wacka) or powered roller, and then lay the concrete minimum 100mm.

No need for expansion joints in this size of slab

No need for a DPM or blinding sand

Brush or stipple the surface, don't trowel it smooth

 

[SiW]

How big does it need to be before Expansion joints are needed and just out of interest how are they formed. Guessing wooden joints rot?????

 

[^woody^]

Joints typically serve several purposes and dimensions can differ. Movement, expansion/contraction, crack control or just construction joints all serve different purposes.

Generally these are only required for large industrial/commercial usage.

4m is about the size for practical levelling due to boards and equipment, so this is often used.

But for a domestic single slab, no joint would be needed in 5m

They are formed by placing compressible material between the two slab edges and then the top sealed with a mastic type sealant

 

[Shytalkz]

Would be worth putting some A142 mesh 35 down from the top of the slab, to control cracking.