Tarmac driveway thickness

[scottS3]

Hi, I am looking at getting my driveway tarmac'd. The first company quote 75mm thick of 70/100 10mm dense material, Breedon Enriched I think is the product. The second crowd say it will only need to be 25mm thick, 6mm material. Both are going on the basis that the existing sub base is sound with it only needing type 1 added where required for levelling etc. I'm confident the sub base is all good as its rock solid and you really need to go at it with a pick axe to break through (its a gravel drive at present).

My question is what thickness of tarmac is right? I know it may vary depending on the actual product use but from 25mm to 75mm is quite a difference. I certainly dont want it done cheap, that being said I'm not keen on being ripped off either.

Cheers

Scott

[soad]

Tirty quid and a dahg...

[scottS3]

I'd love a daag but I'd rather have somewhere nice to park my car first

[AlmostUseful]

25mm of 6mm is sufficient for a footway or vehicle crossover of a footway, but you'd still need a binder course beneath that of circa 50-60mm of 20mm agg.

In my opinion 10mm will leave a more open look and I'd prefer 6mm surface course.

[Steve_W]

Scott, have a poke around on this site - very informative: http://www.pavingexpert.com/tarmac02.htm

[AlmostUseful]

The 75m of 70/100 dense that the first lot quoted is a suitable (albeit too thick) binder course, but will still need finishing off.

[scottS3]

Thanks for the replies. One of my main criteria was that what ever was laid needs to be able to withstand trolley jacks & workshop machinery being lifted using a gantry on castors. The man from Breedon said the product he quoted for was best for this application & the other company just said the 6mm would be fine. I did enquire about have a concrete pad in the area I would be doing this kind of stuff, but both have come back & said there is no need. I have another company coming tomorrow to do a third quote.

[AlmostUseful]

I'd use concrete or blocks if i was going to be jacking, whatever bitmac you use you'll get imprints from jack wheels and stands in anything over about 15 degrees!

[jason61c]

the old boy next to me is looking to get his done. its all concrete at the minute, what sort of thickness would need to go on top? Concrete is very sound.

[TA14]

scottS3 said:

The man from Breedon said the product he quoted for was best for this application.

Did he listen to what you said? A common or garden blacktop with no mention of heavy loads, point loads etc. http://www.breedonaggregates.com/asphalt/asphalt-p...

Now have a look at this one: http://www.breedonaggregates.com/asphalt/asphalt-p... point loads, scuffing, rut resistance, high loads.

Your choice

Edited by TA14 on Monday 29th June 21:21

[guindilias]

Both your links point to the same product.;)

[TA14]

guindilias said:

Both your links point to the same product.;)

Oops, thanks.

[scottS3]

Thanks for the links. I'd take a guess that the industrial stuff will be more expensive, however I will ask the man at Breedon.

[scottS3]

Well the 3rd company have been round, and they suggest a concrete pad in the area where I want to do the lifting/jacking. Then 100mm tarmac to the rest of the areas, 60mm first layer then a 40mm wearing course.

[Spudler]

Sounds ott.
75 (50/25) overall is perfectly adequate.
No benefit from going thicker. As with everything, it's all in the prep.

[scottS3]

Spudler, is it just the thickness of the tarmac that is OTT or is putting down concrete OTT as well?

[TA14]

When I was studying 60/40 was standard for a A road although you'd lay that on a 200 thk basecourse. As Spud suggests 75 overall sounds OK for a driveway. For the point loadings in your case I'd probably choose a concrete area but would be concerned about the visual impact - perhaps edge it with block paving. How did the stronger tarmac price compare?

[scottS3]

I haven't had the quote through for the concrete/tarmac combo yet. The guy was here this morning to size up the job. I know it might not look the best but you cant have everything as they say.

I did consider block paving but I have enough of that already as a patio.

[AlmostUseful]

yup, 60 binder 40 surface is road spec, although we'd probably be more like 90/40 for an A road now.

Just had a look at our standard details and our driveway spec at work is 30mm AC10 Close Graded surface (100/150PEN) and 60mm DBM AC20 (40/60PEN)

You could probably drop to 25/75 but given the laying tolerances going for 30/90 won't hurt.

[BigTom85]

For light duty vehicle use I'd go for a minimum of 150mm type-1 subbase (your existing subbase is probably fine, although once you consider you need to lay 80mm asphalt on top if it, how much will be left?), 60mm thick AC20 and 20mm thick AC6. 100/150 pen is fine for hand laying, if its a big area to be machine laid then go for 40/60 pen. by all means use 30mm thick AC10 but this can look a little coarse for a driveway.

As a rule of thumb each layer needs to be between 2.5 to 3 times the thickness of the largest stone in the material you are using.

I'd get into the habit of using some sheet metal or similar under your jacking points and axle stand points. My tarmac drive is really marked from these things, although I don't care for the time being as I want it block paved in the not-too-distant.

Edited by BigTom85 on Tuesday 30th June 15:27

Edited by BigTom85 on Tuesday 30th June 15:28