I am on a quest to get weed growth on my driveway under control once and for all and keep it that way. I realise that there is no magic solution and that brushing on a monthly basis will be required but I also want to make sure that I am setting myself up for success. Hence I got your book (see pictures) and why I am on this website now.
When I paid through the roof for my house back in 2007 the driveway was one of the standout features that made me want to buy. With the arrival of a couple of kids, work and a bad back caused by damaged L5/L6 vertebrae (like yourself but it would seem no where near as bad) the driveway has fallen away. Its fair to say it has seen better days.
Anyway I am looking for your advice on how best I might fill the joints in between the blocks to help prevent weed growth. The paving is uneven and rounded at the edges which facilitates weed growth around nearly every block. I had previously tried a sealent. I paid a fortune for it and it lasted 2 years. I then tried a dry sand/cement mixture. I just swept it in and allowed the rain to take effect. I did not take the time to go around and pack it in with a copper pipe/trowel (as I have seen on a video recently). I think the unevenness and quantity of the blocks would make this a difficult task but if is what is required then I am willing to do it.
I have attached some pictures of my driveway and I was hoping you might take a look and set me down the right path - no pun intended
with that type of block, you have variable width joints, but at their narrowest they are probably just too narrow for a bound jointing material, such as, say, the new VDW 815 which is intended for 2-6mm joints.
There are weed-proof jointing sands on the market but the only one I've ever seen actually live up to its promise is the BioSand, and even that only gives you 12 months. Beyond that, the manufacturer requires you to jet wash it out and replace with new....that's a nice moneyspinner for them, of course, but it does seem to be the only way to get year-long protection from that product. All of the other alleged weed-proof sands have a working life measured in weeks, it seems.
So, why would anyone use these rather than relying on a good weedkiller? Sodium Chlorate, as nasty and as much of a fire hazard as it is, does a damned fine job, but you can no longer get it without written permission from the Home Secretary, Sepp Blatter and Boutros Boutros Ghali. The next step down is a long-lasting poison based on glyphosate. PathClear is good, but so bloody slow to work, and you are not supposed to use it more than once a year. Resolva is fast but only zaps the current weeds - it doesn't seem to prevent new ones emerging.
On an unsealed section of my own block paved driveway, I'm currently using Resolva to kill off weeds and then PathClear a week or so later to give longer-term protection. It's not 100%, but it is the best combination I've tried to date, and I'd say it's 90-95% effective.
On another part of the driveway which was sealed with a very expensive quality urethane sealant about 5 years ago, the first signs of weed re-colonisation have appeared this year, so that will have to be subjected to the weedkiller treatment any time now, but I have had 5 years without any joint weeds, just a bit of algae/lichen on the surface which washes off easily enough...but at an amortised cost of around 300 quid per year!
The best route for you, I suspect, is to get the whole pavement thoroughly washed and the top 5-8mm of jointing material jetted out, then soak with a long-term weedkiller such as the PathClear, before re-jointing with fresh KDS or BioSand. Regular dousing with Round-Up or Resolva or even bleach will keep colonisation down to a minimum, and it's a very basic, minor task which takes only minutes per month.
If you did want to consider a sealant, then for flexible block paving you really do have to stump up for a top-of-the-range heavy duty sealant to have any chance of it lasting more than 12 months. The problem with far too many of the cheaper sealants for CBPs is that they crack when the blocks move (after all, it *is* a flexible pavement) and that immediately provides ingress for weeds. Oh yes! The surface remains clean-ish and stain resistant, but the joints are compromised, which sort of defeats the object of the exercise.
Tony you're a legend. Thanks for the detailed reply!
The last time I put a sealent on it the guy used picseal. He charged 1,500 I believe. I think a lot of that cost was labour. I watched the video on your youtube channel and it looks fairly straight forward so I might just try and purchase it myself and give it a go.
So my plan is:
- Powerwash
- Biosand - Not sure where I can source this in Ireland. When I type it into google there seems to be a couple of places offering it but more for filtering purposes in septic systems. I presume it will do the same job - http://www.septicsystems.ie/SandPolishingFilters.htm
- Sealent (not sure if you would recommend Picseal?) As I said when the guy did it last time round it was good for 2 years so I would be happy enough with that outcome). If you got 5 years from Resiblock maybe that is the one to go for.
- Apply PathClear
- Brush once a month
- Use Resolva to keep any weeds that sprout up at bay.
Sounds like a good plan to me
Edit - Having done some more research I can see that there is a local supplier that offers jointing sand. They offer 2 types:
"Regular Jointing Sand – Ideal for all paving except for Bergerac or open jointed paving.
Stablising Sand – Used for Bergerac and open jointed paving.Specially designed to “stick� to-gether when its gets wet"
Would a kiln dried silica sand do instead of a biosand or ordinary brush in paving sand?
Stiofain
I recently used resiblock on a small area for my Mum. She is very happy with the result. 9M2 approx took almost 5 liters, with 2 coats. It is not cheap.
I found a company that stocks Biosand but they want to know what the spec of the sand that I need is. I presume he is relating to the number of particles per certain grams or something to that effect. I'm just wondering if you know what I should be looking for here?
Eejits! The BioSand *is* a jointing sand. There's no alternative spec - you can't have, say, superfine BioSand or a-little-bit-coarse BioSand - it's all the same stuff, and it's been designed for used with block paving!
This wouldn't be Ray you were talking to, would it???
Hi Stephen
I know I am new to this forum and do not know what type of sealant you used, but on the contrary I have found it does work very well indeed. I have tried many but would now only use a quality polyurethane one (not acrylic). The sand stays solidly in the joint preventing weed growth. One caveat however - if the paving moves to any significant degree cracks may open up in the bonded sand, where weed growth can occur. However if I get a call from one of my customers (I guarantee no weeds for 3 years) I simply go back pull out the odd weed by hand and place some new sealant in the joint using and old washing up bottle.
Hope that helps?
GGG
