Concrete And Mortar

Mortar consists of cement, builders and and water whilst concrete consists of cement, sharp sand, gravel aggregate and wate. It is important to understand the differences between the two as this is the fundamental premise for any major building work you may carry out.

Additives can also be included in the mix and these will give special properties to the final mix. I will list the most popular additives and the effects each has below:

Plasticizer makes the mortar makes a lot more workable.

Waterproofing agents improve the water resistance of either concrete or mortar.

PVA adhesive imporves the adhseive qualities of the mortar.

For quantities less than a large bucketful it is most convenient to purchase a pre-mixed bag which you can find at most DIY stores. This cuts down on your overall costs and means you are not left with part bag of additives that you may never use or will perhaps degrade over time. Larger quantity means that a trip to the builders merchant will save you money so it's worth taking a trip out to get your "ingredients". Most merchants will offer a free deliver service or if it is chargeable, the cost should be more than acceptable to the cost of the overall project. For larger quantities you will also most probably need an electric or petrol mixer which can usually be hired or if you are lucky borrowed. The prospect of hand mixing a large quantity of concrete or mortar is one not often relished by even the hardiest of builders.

A final alternative is the increasingly popular pre mix delivery which entails a container with a full mix of cement arriving and the mix being poured directly into situ. This is usually more expensive than a hand mix but obvisouly has the benefits of time saving and not to mention an aching back.

Basic mix quantities

This is a rough guide to mixing and each job will have it's own specifics, such as temperature, moisture and location. As a guide 10 Kg of dry ingredients makes about enough mortar to lay somewhere around 15 bricks. Using a standard mix 1:2:4, 2Kg of dry ingerdients (with a low water content and using 20m aggregate) makes approximately 1 cubit meter of wet concrete.

A standard bag of cement weighs fifty kilograms add to this 115Kg of sand and 195Kg of aggregate will give you about .17 cubic mreters of aggregate. To help you get a proportion of what 0.17 meters is, it is enough to pour a slab measuring roughly 1mx1mx150mm and 1 cubic meter is enough for a slab measuring 3.3mx3mx100mm.

So weigh up (no pun intended) what you need and as with everything, it's all in the planning. For some the pre-made and delivered is the way while some like to save the money, keep the budget tight and go all out at the builders yard. Either way, it's not something to be afraid of and most prjects go smoothly - just be patient and take your time and above everything make sure you give it good time to set and keep the pets away from it till it's set!