I have a large driveway with a Type 1 Limestone sub base (actually 4 inches of crushed concrete with 2 inches of MOT on top) and want to top it with tar bonded gravel.
I have had two quotes - one recommends two sprays of tar (i.e. tar, gravel, brush off the loose, another layer of tar then a final layer of gravel) and the other says one layer will be fine (and has never heard of doing two layers- have checked his work elsewhere and it seems fine). Part of the driveway is on a downward slope as you come off the road.
Clearly, one quote is half the price of the other - are two coats necessary? Or should we go with just one layer?
If two coats are better than one, should we double up on the slope or consider a plastic mesh to stop wheel skid? (rear wheel drive car = wheel spin antics ).
And lastly, the sub base does have some areas with very little fines between the larger chunks - would the tar sort this out or should I lay in some fines before application?
obviously two layers will last longer than one, so makes sense to me.
Its a very specialist area, so as long as you've done your research on the reputation of the contractor you choose, you should be fine to take their advice.
Be aware that spray and chip is also very popular with fly by night contractors, who's only specialism is on ripping folks off !
Hi Bobbi - thanks for the response.
Two coats came in at £20 per square metre from one guy and the other was £7.40 psm for one coat. (Both include VAT)
When you're doing 217sqm it kinda makes a big difference in cost!
Both contractors recommended (and def not fly by night / pikeys!!).
Cheers
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