Mortar thickness for first course

[acurachris]

Hi

I've seen posts on this before but slightly different thickness of mortar!

I need four courses to my block and beams from the foundation bottom. The foundation is pretty level although it's higher in one corner by about 20mm. The foundation is 310mm down from my finished B&B level at the high point and 330mm down from the finished B&B level at the other corners.

I would prefer to level the first course if possible although that would mean laying a 30mm mortar bed for a lot of the first course and making the other 10mm or so up over the next three courses. Is 30mm a bit big or will it be okay?

If the whole foundation was level, i could lose the difference over the courses, but as it's higher in one corner, that would be more awkward or is this still the best way? It would mean four 20mm mortar joints in places instead.

Someone mentioned mortar / slate / mortar... to make up the bed, is this still considered good practice?

Or I could try (i have a stone cutter/saw) and cut concrete blocks to 85/90mm high and use these as first row. Better?

Or i could lay concrete blocks on their side as the first course and then have a reduced mortar bed for the remaining courses to about 7-8mm.

Cheers.

 

[^woody^]

The second one

 

[acurachris]

The second one

Thanks for replying.
When you say second, you mean...

Someone mentioned mortar / slate / mortar... to make up the bed, is this still considered good practice?

or

I could try (i have a stone cutter/saw) and cut concrete blocks to 85/90mm high and use these as first row

Cheers

 

[Charlie George]

Use 73mm concrete common for 2/3 course will make it easier.
Jim

 

[^woody^]

lay concrete blocks on their side as the first course and then have a reduced mortar bed for the remaining courses to about 7-8mm

That if it works.
Or a variation.
You don't need to be messing about cutting and splitting blocks.

 

[Charlie George]

Laying a block on its side will leave you 15mm for 4 beds on 310mm end

 

[acurachris]

Thanks for the replies.

Laying a block on its side will leave you 15mm for 4 beds on 310mm end

Yes, I'll work down from the needed level on my gauge rods and will have cut the bottom blocks/use bricks in that particular area as necessary I guess.

Use 73mm concrete common for 2/3 course will make it easier.

Yes, i suppose 73mm would've been better, although I have 65mm engineering bricks now. Might considered this still though! Wanna buy some 65mm engineering bricks?

 

[Charlie George]

Is it not possible to drop height of beam 10mm or so,that would help if not critical,remember beams also have a camber so will be higher in centre.