How to make cold lay asphalt less porous?

Question

Yesterday I finished off a job replacing a gully to add channel drainage on the driveway. The area we dug up (around 2m²) was topped off with 5cm (2") of cold lay asphalt laid in 2x 2.5cm (1") stages. For each stage the asphalt was rammed down hard using a handheld tamper.

Product used: https://www.hanson-packedproducts.co.uk/en/products/asphalts/drive-repair-macadam

The end result is quite a porous asphalt. A lot more noticeably porous than the rest of the driveway which will have been laid with hot asphalt. I'm in the north of England and the freeze-thaw cycle is consistent. I don't want this new patch of asphalt to start breaking up after only a few years.

Is there a technique to finish off cold lay asphalt/tarmac which fills in that porosity?

Thanks.

Answer 1

I would use a sealer and sand, first I would pour the sealer on just enough to almost fill the area, then with clean dry sand sprinkle it on top and work it in so it looks black, when it drys it will be much smother and will not hold water like the porous surface will and the sand provides a binder and helps to reduce the “slick” or slippery texture. I have done this with hot tar and latex sealing blends.