How to work out quantities of materials needed

[JORDANF97]

Looking for advice from professionals. Due to cost I am looking at doing my own patio in my garden. Our house came with a very small area all ready paved, we are looking to rip this out and start a fresh with patio covering a length of 10 metres and a width of 3 metres. I have done a lot of research on how to achieve this through watching videos/speaking to others that have experience and I believe i have got my head around how to complete the job. The problem i am having is how to price up what the job will cost in terms of the materials like MOT type 1 , sharp sand , builders sand and cement. For example going off what i have looked up so far i need to dig down enough to allow for the depth of the paving slabs (which is TBC), 50mm for the bed the slabs will lay on and 100mm for the sub base that will be compacted with a vibration plate compactor using MOT type 1. But how do i go about knowing how much KG of MOT Type 1 i will require. This issue is the same with how much KG of sharp sand, and cement / builders sand (working off a 4 to 1 ratio). I am very much a novice with this and have never layed a patio so i am very concerned at over ordering or unordering on materials due to the time frame i have booked off work or potentially having to throw away left over material. Would really appreciate some guidance on helping roughly work this out from professionals that do this day in day out, Thanks in advance!

[markc]

Work out volume of each material needed in cubic metres and multiply by mass - available online but roughly

hardcore, 1900kgs/cubic meter

sand, dry - 1600kg or 1900kgs wet

cement - 1500 kgs

or concrete around 2400 wet

[markc]

What are you looking to lay as the patio, paving blocks? Slabs? Or tiles etc. this will determine the build up.

[JORDANF97]

We are looking at laying tiles

[markc]

@JORDANF97 tiles are quite unforgiving (unlike block paving, stone or concrete slabs etc.) any movement in the base will be reflected in the tile joints, a mate of mine has put porcelain tiles down and as the clay shrinks and swells the tile joints go uneven and create trip hazards - he laid on a well compacted hardcore plus mortar bed but it moves.

unless you know your ground is very stable then a concrete slab would be best and then lay the tiles similar to indoor floor tiles. 
your build up could then be 75-100mm of well compacted hardcore (type1 or crushed concrete/brick) topped with 75-100mm concrete - no need for a sand blinding or DPM as its outside anyway. Tiles laid on adhesive as advised by tile manufacturer.

working on your 3mx10m - 30sqm area

hardcore - 30m @ 100mm thk is 3cubic metres or approx 5.7t

concrete - 30m @ 75mm thick is just under 2.5 cubic metres (6t approx) or 3 cube at 100mm thick

 

Edited January 17 by markc

[Mr Punter]

If the tiles are the right type you can lay them onto adjustable pedestals.