The Brew Cabin

Posted: **Thu May 26, 2016 8:40 pm**

Hi, after getting some invaluable help from the site ref the front of my house I turn my attention to the back.
I wish to build a raised patio from the rear of my extension, the patio doors will open directly onto it. Height is 1 meter, width and length are both 5 meter.
I want to build it out of block, with a rendered face, and flag the top. One important question I need answered is,
Will I get away with single leaf block?
Also for the back fill I am planning on using brick and concrete rubble I already have in the garden, which I will mix with sharp sand and whack down. Will this suffice?
I plan to put in weep holes and have gravel inside at the base of the w?all to allow drainage.
I will leave enough room at the top to allow for 75 mm of dolomite and 75 mm full coverage cement (1 to 5 sharp sand and cement mix)
I understand my fall needs to be away from the house but I haven't yet worked out what it needs to be. Any idea's greatly appreciated.
Can someone let me know if I'm on the right track.
Cheers

Posted: **Fri May 27, 2016 12:29 am**

single skin of block laid flat but not block laid traditionally

filling with rubble will likely lead to settlement as you won't be able to compact it correctly if you had a month to leave it to settle in might help before topping off the surface

Posted: **Fri May 27, 2016 8:49 pm**

Cheers for that Giles. It had occurred to me I may have to lay the blocks flat. A couple of questions.
What do you recommend back filling with?
Will I be ok putting the top row of blocks only on edge?. I assume these will need to be trimmed to give me my fall away from the house.
Many regards

Posted: **Sat May 28, 2016 8:46 am**

Keep blocks flat and build the fall into the last course by keeping a tight bed at the one end and a fatter bed at the top.
Over that distance a 50mm fall will do. It's a large volume to fill so if you must use your rubble cap it with a weak concrete mix. If there's a lot of rubble you may need to do this in layers, bedding subsequent layers into the concrete. Put your drainage pipes where the last layer finishes when building remaining layers with the granular sub-base. May not be strictly necessary as your paving will prevent any water permeating into the sub-base, but, just in case.

Posted: **Sat May 28, 2016 9:52 am**

we are doing a raised patio on a big house at the moment 1200mm high we are using block and beam and leaving a void underneath rather than filling, but we do a lot of block and beam in house so have access and experience at it.

the best fill is in granular layers of 0-40mm or 0-20mm in layer 100-150 compacted as you go

Posted: **Sat May 28, 2016 10:00 pm**

Giles have you got a wide span for the block and beams for the patio? Are you putting any intermediate supports under the beams to get rid of any flex?

Posted: **Sun May 29, 2016 5:49 pm**

rxbren wrote:Giles have you got a wide span for the block and beams for the patio? Are you putting any intermediate supports under the beams to get rid of any flex?

no only 2m but there is limited bounce once blocked and grouted

Posted: **Thu Jun 02, 2016 1:29 pm**

I too am starting out on a similar build. A raised Patio with rendered walls of side laid blocks filled with compacted rubble,caped with concrete and then porcelain tiles (non-slip R11) finish.

I was expecting to install a damp proof course after a couple of courses of blue engineering bricks. Are you installing a DPC?

This is an diagram of my DPC plan. Is this the approach the pros would take?

Diagram

The Brew Cabin

Raised patio block construction