Bricklaying advice

[Glen H]

Any bricklaying advice out there regarding the best Mix for a garden retaining wall ?

To set the scene – I am planning a level base for a decent sized shed in the garden – but the base will be constructed so as it can be transformed/extended into a brick garage in the future, so the perimeter brickwork will be built up to the DPC and then in-filled with a concrete base that in the future will be the garage floor. (the inner skin will finish 150mm below the outer so as the base can be cast over it.)

This is slightly complicated as this area of the garden drops 800mm over the 20ft base so the base wall also becomes a retaining wall at the bottom end and then backfilled in the middle – I have done proper stepped foundations all around and will be building a double skin wall of the ‘English Bond type’ (or at least up to the DPC level – then transferred into single skin with columns)

Question is - what’s the best mix for the Mortar ? I want to buy the raw materials rather than the pre-mixed bags that cost £££, and was planning 1 part cement to 4 sand to give it a bit extra strength and looking to use the Blue circle ‘Mastercrete’ cement with the additives in but there are 2 types of Mastercrete CEM I and CEM II – which would be the best one ??

Any other advise welcome

[slater]

Mortars

A mortar is a mixture of materials for joining masonry units. The basic materials are cement, sand and water, but other materials such as lime or air-entraining agents (plasticisers) may also be used to improve working properties and durability.

Types of mortar

There are several different types of mortar to consider, and these are set out below.

Cement mortar

This type of mortar in the proportions of 1:3 cement: sand is generally only used for foundations and below damp proof course.

Cement:lime mortar

This has good plasticity and is easy to spread. It also has good water retention and bonding properties.

Air-entrained (plasticised) mortar

This has similar working properties to cement:lime mortar. The entrained air also gives the hardened mortar improved freeze/thaw resistance.

Masonry cement mortar

This combines the features of cement:lime and air-entrained mortars. Blue Circle Masonry Cement mortar is easy to prepare, requiring only the mixing of the cement with sand and water. Neither hydrated lime nor mortar plasticiser is required.

Sulfate-resisting mortar

This type of mortar may be required in some ground conditions or with bricks containing sulfates. Improved resistance to sulfate attack can be provided with Blue Circle Sulfacrete.

Hope this helps as a general rule the mortar should not be stronger than the material to be bonded. General bricklayingis usually 5-1 we use ordinary Portland cement  3-1for roofing Mastercrete does away with the need for any additional placticisers.

Lewis

[Mark Stanton]

1:3 (cement sand) below DPC

1:6 (cement:sand) above DPC

Be careful of height of retained material - if you PM me your e-mail address I have some standard masonry retaining wall details I can send you for guidance if it helps  

[Terry Everall]

For bricks you cant go far wrong with 1cement to 4 sand. Use a palsticer to help workability or try adding washing up "fairy" liquid instead

[Mark Stanton]

Good old Fairy trick - try not to if you can cos it stains brickwork when rained on   and seems to bring out the salts    

[chrisshorty]

6 sand to 1 cement i use fairy all the time on sites and have never had a problem with it so i would say use it you will need someting purely for useability and it save knocking it up all the time with water.

i would get the ordinary blue circle cement with as i have already said fairy.

alo i wouldnt build it in english bond i would just do it normally with wall ties from one skin to the other.

[John Loudon - Sponsorship Liaison]

Use lime instead of fairy. I used 5 :1 on my recent project. b****y stuff gets everywhere and on everything. Also worth getting one of these if you are doing a lot and have little experience. It makes life a lot easier

[Glen H]

Cheers guys - all useful stuff I will take on board but no-one has advised on the 2 types of Mastercrete so if anyone has an opinion on this then please shout up - these already have the Palsticiser's mixed in so no need for the fairy

Mark - PM coming your way

John - Brciky tool is sat waiting in the Shed.

Glen

[pistonbroke]

dont lay brick if theres any danger of frost it'll blow the cement  

[Man On The Clapham Omnibus]

What kind of sand is right for this chaps? Maybe any kind... I see 'sharp' and 'soft' in my travels.

[dombanks]

is brick laying difficult with one of those tool things?

i want to replace some of the windows in my conservatory with a solid wall. i was thinking about doing it myself but have always been put off by the brick laying part of it. I asked the guy who was bulding next doors wall on their conservatory and he said it was too small a job for him to care. the wall is not load bearing and backs onto nextdoors wall so it doesnt have to be great.

[dhutch]

Its not mega hard at all.

- If its not going to be seen from the outside, and plastered on the inside, i would be be happy to do it.

- If your inexperienced (like me) then the thing that changes is just that it takes longer to attachive the same goal.

You can get it as good and a stright. You just ended up taking one in five bricks back off to add more motor, cleaning up more motor, messing around with bits of string more, or whatever.

Daniel

[Glen H]

What kind of sand is right for this chaps? Maybe any kind... I see 'sharp' and 'soft' in my travels.

'Soft' or otherwise known as 'Builders sand' is for Mortar.

[dhutch]

Sharp is used for concreteing, and not a huge amount else.

[Man On The Clapham Omnibus]

Glen H, dhutch, thanks!