Get the latest news, expert advice and product inspiration straight to your inbox. If the slabs are bedded on concrete or cement-based mortar, you’ll have more of a chance with pointing or grouting. The first type of sand used is the soft sand, also known as builders sand. Building sand is not used for the laying of block paving or paving slabs unless it is combined with cement and even this mixture can be too soft to lay paving slabs upon. 2. An easy way to achieve this is to gently rub the filled joint with a stick or rubber, and then to softly brush it over before it dries, To avoid the new mortar drying out too quickly, spray the joints lightly with water from time to time. The structural soundness of a render depends on the bonding with the background and between coats. The other type of sand is sharp sand. Either is fine it'll be more difficult to get wet mortar between the slabs where as you can brush in a sand and cement lean mix and let nature do the rest, I'd say though the only thing you'll have to think about is if you want to 'point' between the slabs you won't be able to if you brush in You can also purchase ready-made objects in lawn and garden shops or hobby and craft stores. Pre-mixed roof mortars are also available that are accepted by the NHBC. Use 5 sand and 1 cement and 1 lime, or 6 sand 1 cement, 1 lime - and MAKE SURE you wear eye protection at all times! If you use soft building sand to lay block paving upon it will eventually lead to the paving sinking. Measure the amounts carefully so that each batch will set to a consistent colouring. Incorrect pointing causes irreparable damage to older buildings. Joints deeper than 20 mm will need an initial dubbing out as shrinkage can occur otherwise. Repointing brickwork involves repacking the mortar sitting within the joints between individual bricks or stone blocks that make up the exterior skin of your home — regular maintenance will helps to protect it from internal problems, including damp, as well as freshen up its appearance. If you use soft building sand to lay block paving upon it will eventually lead to the paving sinking. keystone Forumite. I find it easier to make up a fairly dry "biscuit crumb" mix with just a small amount of water. However sharp sand is too 'gritty' for pointing and laying bricks with so builders sand is used. Other aspects, such as the type of brick or stone, or the sand being used will affect the final mix. Mortar is the substance that separates individual masonry units (such as bricks or stone blocks) from one another. How much cement would I need to mix in? Natural Hydraulic Lime mortar consists of two building materials, lime and sand. NHL 3.5 Moderately Hydraulic Lime can be used for permeable masonry materials which is mainly used above ground. Power cables for external lighting is often run inside the pointing so take care. Generally, it is used for bricks, facings, commons, blockwork, bedding, sandstone, limestone, flint, terracotta, cavity and solid walls, pointing or repointing. Builder's sand (or bricklayer's sand) is finer and softer and mixed with cement and water to produce the mortar for laying bricks and blocks. After all, sand is the biggest ingredient of mortar. The base I need is about 3.3m x 2.7m at around 4 inches depth on average. Sand in all its forms has so many uses, but if you get the grade or name of sand wrong, the results can be pretty damaging to your project & reputation.There are over 20 different names for sand & bedding sand itself has over 10 different names. It is used in concrete and can also be used for rendering walls and floors. However, the first half metre of a solid wall without a damp-proof course (as here) holds a lot of moisture so this section is done first — giving it more time to dry. How long the drying process takes depends on the weather and the position of the house in relation to the sun. 0. Repointing brickwork should be high on the priority list when renovating a house. Hi you use both. The mix proportions provide below are a guide from which a mix can be selected to suit the construction and local environmental conditions. Thank you . Then lay your plastic sheet on the ground a short distance from where you are going to use the mortar. Historic lime mortar usually consists of soft sand, sharp sand and N.H.L 3.5 hydraulic lime. NHL 5 … Then lay your plastic sheet on the ground a short distance from where you are going to use the mortar. Always dry lay your patio first, a simple job of laying out the paving as you want the finished patio to be. For information on HYDRAULIC LIME MORTAR please click the lime mortar tab on the menu. Building sand is not used for the laying of block paving or paving slabs unless it is combined with cement and even this mixture can be too soft to lay paving slabs upon. Repointing brickwork is clearly high priority on this wall. Weather struck joints rebate under the stone above and are flush to the edge of the stone below the joint. However what ratio needs to be followed for Stonework pointing 4:1:1 4 sand : 1 OPC 1: Lime. Whether your house is constructed from brick or stone, mortar can make up as much as 15% of its overall surface area — so it isn’t hard to see what a huge impact repointing brickwork can have not only on the stability and performance of your home, but also on its final appearance. Within five hours, a team of two complete this stage on this 24m2 wall. However, if there are open or poorly filled joints that offer no resistance at all then selective repointing will be required. misterhelpful, 24 Mar 2012 #2. Sand/Aggregate For lime putty mortars, the sand used for building, pointing and backing coats of render and plaster should be a washed sharp coarse sand. Pointing of all kinds should be carried out on a dry day and when your patio itself is dry. For high traffic areas, a stronger mix of 3 parts soft sand and 1 part cement can be used.