The Brew Cabin

Posted: **Wed Jul 13, 2005 4:17 pm**

Hi, half way through laying 50 square metres of Indian Sandstone (3 sizes). I'm leaving a 10mm gap between flags as this is what the 3 size pattern requires. One edge of the patio is up against my house and is therefore fixed.

It was all going well until I have moved further down the edge of my house (I'm about half way down the house). I'm not sure for the reason, but I'm finding it more and more difficult to fit the flags in with a 10mm mortar. At times the gap is reduced to half that, and at worst in a couple of places the flags are nearly touching. This is only affecting 4 or so flags at the moment. I cannot see why this would be happening unless a) the house is not straight or b) my flags are not uniform width and/or are not square.

The other side of the patio is not fixed and will join a lawn so this can move slightly if required. I've stopped at the moment to try and resolve this, rather than carry on and the problem getting worse and worse and eventually not being able to fit a flag in the required area.

Any advice as to how to proceed would be greatly appreciated. I would rather remedy the problem now and allow proper widths for the remaining half of the patio.

Please help as I am low on moral

Posted: **Thu Jul 14, 2005 3:53 pm**

The reason for your problem is explained right at the bottom of the Random Layouts page.

Let's say you have a 900mm flag and you lay two 450mm flags alongside. You'd think they'd match exactly, but because there needs to be a 10mm joint, you actually end up with 450+10+450=910mm. If you use three 300mm flags, it's even worse, as you get 300+10+300+10+300=920mm.

With all these random layouts, you need to 'balance' the joints. Ideally, you aim for a 10-12mm joint, but you have to accept that some will be 8mm and some will be 15-18mm. No joint should be less than 6mm and none wider than 20mm as absolute min-max values.

So: you lay and area of paving, then stand back and 'spread' the joints to even them out. Some will be opened up a touch, other's might be closed down a smidgen, but the overall aim is to create a balanced look, with all joints in the 8-18mm range as far as possible.

Only after the joints have been balanced should you point up. If you point up before balancing the joints, you end up having to redo the lot.

Posted: **Thu Jul 21, 2005 9:14 am**

Thanks for the advice Tony. I have discovered that the extension on the house is not actually true square so the further along I got, the tighter it got.

To combat this, I left the flag against the house out as they would need to be trimmed. I carried on finishing everything else and then did all the cuts at the end.

The Brew Cabin

Help! joint widths decreasing whilst laying riven - How can i sort this out