Problems.

[Mad_angler1]

Hi guys new here but followed this site extensively, just laid 3 weeks ago 50msq of block paving in the garden. It's a rectangle walled in on a angle as the whole garden runs back towards the house, about 3ft rise from top to bottom, could not lay it level due to garage at top, at the bottom end it meets a wall that drops 4ft to the next level. On one side of the wall steps are cut into it and along the rest of the wall in iv installed drainage channel that moves water down to the next level

The problem I have is after rain we have had in the last 2 days some of the blocks in front of the steps have sunk when stepped on, iv lifted a few and the bedding layer has basically liquified.

It all was installed with between 100 and 150mm of MOT1 on top of fabric and stone dust bedding layer at a minimum of 25mm but at this particular point it's quite deep around 80mm as I had to make up to the level of the steps,

Not sure what to do next, after some checks this dust does not seem to react well with water just goes to mush, it was recommended by Travis perking as the stuff every one uses so I'm not sure what to do next

Any ideas as I'm concerned the whole thing is going to go this way

Thanks in advance

[Dave_L]

Bedding layer incorrect material and much too deep.

I fear there is only one answer and you aren't going to like it - but I'll leave it to the block paving guys.

[r896neo]

80mm is far too deep as you know. Quarry dust is also widely quoted by armchair tradesmen such as counter staff in merchants as ''oh this is what everyone lays on''

I was in B&Q looking for a tiny amount of MOT type 1 to finish a small job, i only needed maybe 75KG and i couldn;t find it so i asked. He took me over to the quarry dust and said, this is what you want. He then proceeded to argue with me when i told him he was totally wrong, saying all the guys that come in here use that.

As you have found to your cost it holds water like a sponge.

I'm sorry there is no easy way to say this but as Dave mentioned you should lift it and relay. The sooner you do it the cleaner the blocks will come up.

[Mad_angler1]

Thanks guys, seriously not happy re the dust a I specifically went to order the correct sand and was told to use the dust as it was what everyone used.

What I'm hopping I will get away with os lifting that perticular part a few feet around build up with mot1 and lay those on sand.

Lifting the whole lot is not an option right now due to other things but I do appreciate your advice.

I'm hopping as it the lowest point that's adding to the problem so if I resolve that the rest will be ok.

[Bob_A]

it was recommended by Travis perking as the stuff every one uses so I'm not sure what to do next

Sounds typical of my local TP who took over my very good independent builders merchant and fecked it up.

Bet you was charged way over the odds as well

[seanandruby]

Photos would be good. You need to lift and relay.

[Dave_L]

Yes I'm sure a localised lift and relay making sure the bedding is at the correct layer thickness will remedy the problem in the short term.

Don't worry, us professionals don't always get it right..............

[lutonlagerlout]

as said
lift and relay the affected areas with type 1 and 35mm of compacted grit sand
LLL

[Mad_angler1]

Hi guys got another question. I used 4 pallets to do the top section of the garden. After laying I noticed we had a distinct colour diferance between the first 2 pallets and the second two, they were delivered 2 days apart from the same place, as we finished the first two almost on a straight line its very noticeable, the fist ones almost look wet compared to the second ones that look far drier

I'm hoping it will weather out but any ideas

see below pick

[rimexboy]

The best you can do now is try and mix them in...

When you buy x amount you mix as you lay to avoid what you have got now..

[mickg]

you should always lay from 2 - 3 packs of block at the same time so they are blended together, the effect what you have got is because you laid 1 pack at a time

[TheRockConcreting]

It's not something i've ever done, but won't sealing solve this problem?

[lutonlagerlout]

as mick said you should always mix from all the packs at once
however the darker ones just look a bit wetter to me
give it a while and they will blend
LLL

[Dave_L]

I'd give it a summer and towards the end when the blocks are as dry as can be, seal them with a sealant.

I know the pros here don't endorse it but I had a similar problem and sealed the driveway with Thomsons Driveway Seal (in a gold can) and it sorted the problem, the customer was happy.

Making sure the blocks are dry is the key here otherwise you are just sealing in moisture which will cause you grief.....