Cement and mortar.......

[chris lowe]

Hi all, I'm aiming to build a small retaining wall in my back garden and am a tad confused about the 'ingredients' needed. Can I just mix a bag cement with the appropriate amount of sand and add water or do I have to add lime as well? I'm going to have a small foundation and then a single skin wall. Are the mixes for the foundation and mortar different? As you can tell I"m a bit of a novice so any advice would be most appreciated Cheers Chris

[Andrew Gabriel]

In this context, lime acts as a plasticiser, making the mortar nicer to handle. You can buy plasticiser as an additive to the water instead. You don't have to use it at all though.

A retaining wall isn't a completely trivial task though. There are two issues -- walls have to be specially designed to hold back a bank of earth, or the earth will just push the wall over. You need to think about how moisture is going to be handled. The earth will keep the wall wet, which will make it liable to frost damage depending on the absorbancy of the bricks used, and it will force salts through the wall which can result in staining of the brickwork. You need to arrange for drainage from the soil, and you should either use a waterproof membrane to protect the brickwork or use low absorbancy (engineering) bricks.

Foundations would normally be concrete, not mortar.

[chris lowe]

SO what is the difference between concrete and mortar??

[ARWadsworth]

may get you started Chris.

HTH

Adam

[chris lowe]

thanks!!!!

[Astral Voyager]

My brother-in-law, a brikkie, always puts a shot of washing up liquid in the mix. I assume this is to do the same job.

Mel W.

[Mike P]

.. >

.. >"Andrew Gabriel" wrote: .. >

.. >> In this context, lime acts as a plasticiser, making the mortar .. >> nicer to handle. You can buy plasticiser as an additive to the .. >> water instead. You don't have to use it at all though. .. >

.. >My brother-in-law, a brikkie, always puts a shot of washing up liquid in the .. >mix. I assume this is to do the same job. .. >

.. >Mel W. .. >

Yes .. works a treat .............. and makes the cement smell real nice if you use a lemony one ;-)

Mike P

[chris lowe]

Ok then I'll make sure I get the grapefruit flavour - much nicer.............!!!!!!!!!

[Rick]

1 bag of cement = 2 buckets of cement = 4 shovels. So a now you can work out how many shovels of sand to use. I mix 1/2 a bag of cement at a time. I avoid very hot times of day when the stuff dries before it sets. Use a mixer to get the consistancy right as thats real important You can use a plasticiser, but most modern cements contain some. Unless the retaining wall is high, then no need to worry about engineers caculations. You need weep holes for water in the bottom of the wall, drill them in when you are done. You need a trowel of the right size, with a BIG handle. I use a 6 inch rounded one, not the big 9 inch ones. I built a while house using these "tips" having never done any brick work before.

Rick