How essential to lay MOT right level?

[markyyyyyy]

I’ve compacted my MOT for patio base. There are a couple of areas that are 10-15mm lower than some other areas, is this ok to just use more mortar when laying the slabs (Indian stone)?

Cheers

 

[Notch7]

Provided the overall level is about right, then some localised dips are fine

It’s hard to compact MOT and get it perfect

 

[markyyyyyy]

Ah that’s ok then. I’ve just run a string line from the top of the edge to top of the other edges (finished level of patio) and most areas are approx 75mm (which is correct height I need) and some areas are 80-90mm so I expect I’ll be ok.

I do actually have some MOT left over, is it worth putting a bit more down or is it neither here or there just using more mortar to bring to required height?

 

[SFK]

The more level the MOT, the easier it will be to get the mortar bed right.

And now you have asked, you should do it now otherwise you will kick yourself later.

 

[noseall]

The more level the MOT, the easier it will be to get the mortar bed right.

Whilst there is a lot of truth in that, the main obstacle or hindrance is the calibration of the slabs.

MOT accuracy will deal with the depth or consistency of the depth of mortar bed. However, slabbing becomes infinitely more difficult when the slabs themselves vary massively in thickness.

Even calibrated slabs - píss easy to lay.
Varying thickness slabs - forever lifting and scraping or adding.

Píss easy slabs.....

spot.jpg

• noseall
• 20 Dec 2023

digby3.jpg

• noseall
• 20 Oct 2023

spot2.jpg

• noseall
• 20 Dec 2023

spot3.jpg

• noseall
• 20 Dec 2023

 

[markyyyyyy]

Whilst there is a lot of truth in that, the main obstacle or hindrance is the calibration of the slabs.

MOT accuracy will deal with the depth or consistency of the depth of mortar bed. However, slabbing becomes infinitely more difficult when the slabs themselves vary massively in thickness.

Even calibrated slabs - píss easy to lay.
Varying thickness slabs - forever lifting and scraping or adding.

Píss easy slabs.....

spot.jpg

• noseall
• 20 Dec 2023

digby3.jpg

• noseall
• 20 Oct 2023

spot2.jpg

• noseall
• 20 Dec 2023

spot3.jpg

• noseall
• 20 Dec 2023

So are we saying that you believe I don’t need to adjust the MOT, and just level slabs with mortar bed and mallet the Indian stone level?

 

[noseall]

So are we saying that you believe I don’t need to adjust the MOT,

As long as it's not too high - no.

 

[markyyyyyy]

As long as it's not too high - no.

So in my case 15mm in small sections discrepancy is good?

 

[noseall]

So are we saying that you believe I don’t need to adjust the MOT

Our MOT is up nd down like a horses arse...

mot1.jpg

• noseall
• 9 Mar 2024

 

[23vc]

The MOT should be sloped to the drainage fall too

 

[noseall]

So in my case 15mm in small sections discrepancy is good?

15mm? Are you having a larf? We did end up scraping a wee bit off with the grader (machine excavator), as we were a wee bit too high in places.

 

[Charlie George]

Your beds a bit on the large side, over 60mm in places, you will need about 1.3 tonne of sand at that depth and 9/10 cement, you could top up the MOT a little to save on mixing especially if you've got leftover.

 

[23vc]

Our MOT is up nd down like a horses arse...

mot1.jpg

• noseall
• 9 Mar 2024

What are those smooth ones sold as/called? They look the nuts
Someone’s sheeted them out well for rendering…

 

[markyyyyyy]

Your beds a bit on the large side, over 60mm in places, you will need about 1.3 tonne of sand at that depth and 9/10 cement, you could top up the MOT a little to save on mixing especially if you've got leftover.

I’ve left approx 75mm depth in most areas for:

50mm mortar bed
22mm paving

This will bring me to the correct level (with top of concrete edge) once installed

 

[markyyyyyy]

What are those smooth ones sold as/called? They look the nuts
Someone’s sheeted them out well for rendering…

Ah sorry, yes I see what you mean!