Types Brick as masonry

Bond is a pattern in which the bricks / Stones / AAC blocks/concrete blocks are laid as walls, paving to provide the strength, durability, uniformity and good look. There are many types of bonds based on the look, method of installation and structural considerations.

Mainly or most widely used masonry bonds are:

     1.     Stretcher Bond / Running Bond

     2.     Header Bond

     3.     English Bond

     4.     Flemish Bond

a.     Single Flemish Bond

b.     Double Flemish Bond

    5.     Dutch Bond

    6.     Common Bond / American Bond

    7.     Facing Bond

    8.     Rat Trap Bond

    9.     Edge bond (Silverlock’s bond or Soldier’s course)

   10.  Raking bond:

a.     Diagonal Bond

b.     Herring-bone bond

   11.  Zigzag bond

   12.  Garden wall bond

a.     English Garden wall bond

b.     Flemish Garden wall bond

   13.  Sussex bond

   14.  Dearne’s bond

   15.  Stack Bond

    Let see the pattern of each bond:

1.     Stretcher Bond / Running Bond:

     2.     Header Bond

     3.     English Bond

     4.     Flemish Bond

a.     Single Flemish Bond

b.     Double Flemish Bond

    5.     Dutch Bond

    6.     Common Bond / American Bond

    7.     Facing Bond

    8.     Rat Trap Bond

    9.     Edge bond (Silverlock’s bond or Soldier’s course)

   10.  Raking bond:

a.     Diagonal Bond

b.     Herring-bone bond

   11.  Zigzag bond

   12.  Garden wall bond

a.     English Garden wall bond

b.     Flemish Garden wall bond

   13.  Sussex bond

   14.  Dearne’s bond

   15.  Stack Bond 

    Cutting the blocks / bricks:

     

Other than building wall, especially bricks were used for waterproofing material normally said as "Brick Bat Coba". Brickbat waterproofing is one of the oldest methods of waterproofing, and with new modern waterproofing products available in the market, brickbat waterproofing has become absolute these days.

General specificaiton of brick bat coba is: 

Application of Slurry under Base coat: The bonding slurry (prepared using E 135, water and cement in ratio of 1:1:3) shall be applied over the dampened surface with brushes including the joints between the floor slab and the parapet wall, holes on the surfaces and joints of pipes in masonry/concrete. The application of the slurry should continue up to a height of 300 mm over the adjacent wall. Bonding slurry should also be applied up to a height of 150 mm over pipe projection etc.
Laying Base coat: Install 25mm thick mortar (prepared using CM 1:4 admixed with E 160 at a dosage of 200 ml per bag of 50 Kg cement), over the wet / tacky bonding slurry. Packing all corners and pipe penetrations. The application of the mortar shall be continued up to a height of 300 mm over the adjacent walls.
Placing of Brick bat: Brick bats of size 40 (Or lesser depending the minimum thickness of Brick Bat Coba) to 75mm thick shall be placed over the mortar bed by hand packing having minimum 15mm thick mortar below the brick bats and suitable gaps in between. Only fully burnt bricks shall be used and the brick bats shall be well soaked before laying. Application of another layer of bonding slurry after curing of the above surface for a minimum period of 24 hours. Then filling the gaps between the brick bats with mortar.
Laying Finishing Layer: Immediately on applying the mortar is still green, a 20mm thick layer of mortar, without leaving any joints shall be applied over the entire surface including the coving. The surface shall be neatly finished with bonding slurry and finished smooth with steel trowel. The surface shall have proper slope towards the drain out let pipe. The finished surface shall be allowed to dry for a while till a string mark can easily be made on the surface, when 300mm x 300 mm square marks shall be made over the entire surface.
Curing: The entire surface shall be flooded with water by making bunds with weak cement mortar, water shall be made to remain on the surface for a minimum period of two weeks during which it can be observed if there are any leakage or not.

    

Advantages of brick bat coba:

1. Can be done by used / broken bricks.

2. Can be left exposed for foot traffic.

3. Option to provide slope.

Disadvantages of brick bat coba:

1. Increase in load because of use of brick, sand, cement at higher thickness.

2. Consumes time, manpower.

3. Need skilled man-power.

4. Possible mistakes in the workmen ship.

5. Rigid, not flexible, hold water in it.

6. Thermally, not stable and non-UV

7. Verry difficult to repair, if leakage found.

Because of modern construction chemicals, this has been replaced by liquid-applied coating and sheet applied membranes. But, still, some prefer to use coba system by adding construction chemicals like integral / crystalline, etc admixtures including replacing the brick with lightweight aggregates like thermocol.

Many thanks to Google.com, Doc88.com and to my teachers..... from where these details were collected.

Common doubts in Waterproofing

1.   When we are using the primer, why should we do surface preparation very thoroughly? Primer should work as good bonding agent in between.            

Primer applied on the non-prepared surface, primer will stick to the contaminants. But this does not mean that the contaminants will remain bonded to the surface. Hence, the subsequent applied material will bond to the contaminants at the bottom and contaminants leaves the surface.

2. What tile adhesive shall be used on waterproofing coating? All adhesives should work. Even on polyurethane coating?

This doubt is very simple, but the answer is in chemistry of the product. All waterproofing coatings works for one goal and that is waterproofing the surface but chemically they are/may be different. For examples, Acrylic, cementitious acrylic, SBR based, Integral based, Crystalline based – these are good compatible with cementitious tile adhesive. Some type of waterproofing membrane like, polyurea, polyurethane, urethane is very different from the previous ones. These are made up of very close linked polymer structure, hence they form vert tight surface which will not allow subsequent material to bond by mechanically and even not by chemically. So, we have 2 options, first to ask the manufacturer that which adhesive is compatible and the second is to conduct the Pull-Off test at site level and take a joint decision along with client.

3.  Need to create the slope (Avg 2-5mm thick) over the waterproofing coating which is 1.2mm thick. Can we use cement slurry?

Generally waterproofing membranes are flexible as they must be stretchable to bridge the crack.

Cement slurry which will become rigid after drying will have low tensile strength, applied on waterproofing membranes, it will crack. Hence, it is recommended to apply any flexible levelling compound over the waterproofing membranes. This type of flexible levelling compounds will have more tensile strength and will not crack.

In case, if the thickness of sloping material is high say min 15mm, then it can be done with Cement sand mortar with/without admixed with admixture say, integral/crystalline/SBR, etc.

4. Vitrified tiles installed using Pre-mixed adhesive over the waterproofing coating is failed. Then, how can you say tile adhesive will work in this case?

Before we get in the answer, first let us understand how Pre-mixed adhesive and adhesive works differently.

Pre-mixed adhesive means formulated powder mixed with formulated liquid, supplied in air tight product. When you apply this adhesive, it starts de-hydration, liquid part evaporates, material get hard as tile bed bonding with the tile bottom and the surface. Tiles adhesive are supplied in the powder form, needs to mix with water and then applied. Polymer/chemical will hold the water, chemical utilizes while reaction and forms hard tile bed bonding between the tile bottom and the surface.

In this case, client used Premixed adhesive to install the vitrified tile which are impermeable, over the waterproofing coating which is also impermeable, then where is the way to liquid to evaporate? Adhesive remains wet, does not dry almost same as the air-tight bag. So, it will not get hard, not create the bond with tile or with the surface. In case if client use tile adhesive, tile adhesive does not need space to evaporate the water, it will use the water in chemical reaction, dries, get hard, achieve good bond with tile and surface.

5. Why we cannot use any primer / sealer for any toping material, as all primer and sealer will seal the porosity of the surface and provide the clean surface?

Primer and sealer are not same by function and by the chemistry. Primers, seals the surface, supress the fine dust (up to certain limit), bonds to the surface chemical/mechanically, provides chemically compatible surface for toping material. Whereas sealers, seals the surface, provides different look to the surface, provides breathability to the surface (some sealers only) and in most cases they do not gives compatible surface to the other toping materials.

Manufacturer designs the chemistry of the primer according the system. So, it is not good for client or to an applicator to re-design the system and test.

6. Client and applicator says there is problem in the product. Applicator says, he is using our product and similar other’s product since many years and not seen this type of problem.

Whenever the problem rises at site level, it is obvious that everyone put blame on the product sometimes the sales officers of the manufacturer also. Here, everyone should know that all manufacturer has some set of rules to be followed before production and the stores department releases the product to the market. Once the technical team and R&D, finalize the product, production department produces the product and pack it. Technical team, randomly pick the packed product and conduct the testing. After passing all the test, product will be approved to handover to the stores department. Products will be manufactured in tons together in batch wise. These products will be dispatched to the end users as per request.

Let us assume, that there is a complaint in the product, then this should be reported from all the places where product has been sent. How comes, only one site or two sites will have the problem?

Other than this, it is necessary to observe the site condition and the site work procedure where there are multiple peoples will be working with their own set of rules and knowledge under different site condition.

For still more problems before application, while application and after application, please refer to:

https://annayyachandrashekar.blogspot.com/2018/03/protect-products-from-nature-so-that.html

https://annayyachandrashekar.blogspot.com/2018/11/problems-and-solution-in-resin-flooring.html

As per the time line, we try to keep this data updated.

Common doubts in Tiling

1. What tile adhesive shall be used on waterproofing coating? All adhesives should work. Even on polyurethane coating?

This doubt is very simple, but the answer is in chemistry of the product. All waterproofing coatings works for one goal and that is waterproofing the surface but chemically they are/may be different. For examples, Acrylic, cementitious acrylic, SBR based, Integral based, Crystalline based – these are good compatible with cementitious tile adhesive. Some type of waterproofing membrane like, polyurea, polyurethane, urethane is very different from the previous ones. These are made up of very close linked polymer structure, hence they form vert tight surface which will not allow subsequent material to bond by mechanically and even not by chemically. So, we have 2 options, first to ask the manufacturer that which adhesive is compatible and the second is to conduct the Pull-Off test at site level and take a joint decision along with client.

2. Vitrified tiles installed using Pre-mixed adhesive over the waterproofing coating is failed. Then, how can you say tile adhesive will work in this case?

Before we get in the answer, first let us understand how Pre-mixed adhesive and adhesive works differently.

Pre-mixed adhesive means formulated powder mixed with formulated liquid, supplied in air tight product. When you apply this adhesive, it starts de-hydration, liquid part evaporates, material get hard as tile bed bonding with the tile bottom and the surface. Tiles adhesive are supplied in the powder form, needs to mix with water and then applied. Polymer/chemical will hold the water, chemical utilizes while reaction and forms hard tile bed bonding between the tile bottom and the surface.

In this case, client used Premixed adhesive to install the vitrified tile which are impermeable, over the waterproofing coating which is also impermeable, then where is the way to liquid to evaporate? Adhesive remains wet, does not dry almost same as the air-tight bag. So, it will not get hard, not create the bond with tile or with the surface. In case if client use tile adhesive, tile adhesive does not need space to evaporate the water, it will use the water in chemical reaction, dries, get hard, achieve good bond with tile and surface.

3. Why we cannot use any primer / sealer for any toping material, as all primer and sealer will seal the porosity of the surface and provide the clean surface?

Primer and sealer are not same by function and by the chemistry. Primers, seals the surface, supress the fine dust (up to certain limit), bonds to the surface chemical/mechanically, provides chemically compatible surface for toping material. Whereas sealers, seals the surface, provides different look to the surface, provides breathability to the surface (some sealers only) and in most cases they do not gives compatible surface to the other toping materials.

Manufacturer designs the chemistry of the primer according the system. So, it is not good for client or to an applicator to re-design the system and test.

4. Moisture testing is necessary for the old and visible dry floors/walls?

There are 2 types of moisture in the structure. Surface moisture and the rising moisture. Moisture which is on the surface is surface moisture. Moisture in the matrix of the substrate but may/may not be on surface is supressed moisture and this may rise to the surface anytime, so it is called as rising moisture. Sometimes moisture may rise to the surface from the water sources like, pond, garden, river, water pipe leakage, etc., hence this is also called as rising moisture.

Surface moisture and moisture from the water pipe line leakage may be at any floor level of the structure. Whereas, rising moisture will be at the floor which is next to the soil or below soil level.

Considering the both situation, it is always suggested to the moisture test at least by plastic sheet method Or simple apply (DPM) Damp Proof Membrane.

For more accuracy, you can use electronic moisture testing instruments for surface moisture test and deep moisture test. For more details on moisture testing, refer: https://annayyachandrashekar.blogspot.com/2017/09/moisture-testing.html

5. Client and applicator says there is problem in the product. Applicator says, he is using our product and similar other’s product since many years and not seen this type of problem.

Whenever the problem rises at site level, it is obvious that everyone put blame on the product sometimes the sales officers of the manufacturer also. Here, everyone should know that all manufacturer has some set of rules to be followed before production and the stores department releases the product to the market. Once the technical team and R&D, finalize the product, production department produces the product and pack it. Technical team, randomly pick the packed product and conduct the testing. After passing all the test, product will be approved to handover to the stores department. Products will be manufactured in tons together in batch wise. These products will be dispatched to the end users as per request.

Let us assume, that there is a complaint in the product, then this should be reported from all the places where product has been sent. How comes, only one site or two sites will have the problem?

Other than this, it is necessary to observe the site condition and the site work procedure where there are multiple peoples will be working with their own set of rules and knowledge under different site condition.

6. Mesh Backed Stone / tile and Mosaics, de-bonded. Why?

If the following points are not observed, followed, then the failure is guaranteed. 

• All mesh/backing must be well adhered to the tiles, Mosaics with any form of mesh backing, and stone tiles which are resin mesh backed are not suitable for external wall tiling.

• At least 75% of the stone tile rear face must be exposed and fixed with tile adhesive – otherwise the tiles must be mechanically fixed. At least 75% of the mosaic tessera rear faces must be exposed and fixed with tile adhesive, the backing mesh must not deteriorate in service, otherwise mosaic tiles cannot be used.

• The mesh/backing on mosaics for wet/external areas must be water-resistant and the mesh glue should show no loss of adhesion with prolonged immersion.

(as per BS 5385 and The Stone Federation guidance - Appendix.

For still more problems before application, while application and after application, please refer to:

https://annayyachandrashekar.blogspot.com/2018/03/protect-products-from-nature-so-that.html

https://annayyachandrashekar.blogspot.com/2018/11/problems-and-solution-in-resin-flooring.html

As per the time line, we try to keep this data updated.

Hollow sound in tiles: Good or bad?

What is hollow sound:

When tile / stone hit, if the sound heard was high-pitched sound, then it the tile stone were bonded good. If you hear a lower-pitched sound, then there is gap between the stone to adhesive OR adhesive to substrate and this is called hollow sound.

How to test the hollowness?

>             Coin hit test.

>             Steel ball bearing hit test.

>             Metallic chain beat test.

>             Metallic chain beat test. (It may break your tile/stones)

>        Adjustable Hollowing Hammer Test Drumstick 
                                              

Why hollowness occurs?

>             Un-sound substrate.

>             Improper surface preparation.

>             Inadequate thickness of the adhesive.

>             Contaminants at back of tile / stones.

>             Installation of tile/stone on the finished open time adhesive, i.e., skin formed adhesive.

>             No twisting action at the time of installation of tile/stone.

>             Substrate deflection, vibration, movement.

>             Installation of tile / stone on movement / expansion joints.

Hollow sound is good when tile / stone were installed on:

>             a less-dense substrate material, for example, wood versus concrete

>             a substrate or configuration that has open (hollow) spaces, for example, a wood-framed         floor or steel-framed wall

>             an installation substrate or component with intentional voids – for example, some                 uncoupling membranes and hollow-core concrete slabs.

>             In spot bonding method at wall area.

Many thanks to Google.com, Doc89.com, CNA Handbook,

Why to maintain tile & stone joints grout?

Nothing is static. It is known to everyone that everything in this world moves at its own speed or due to its properties and it is especially true in buildings. Concrete and mortar expand and contracts so do with wood and other building materials also. Hence, the basic answer is the movement and it is very important to accommodate this movement or else this movement will cause the failure of the materials installed. Here are some of the failures caused by the movement:-

In the above photos, it is observable that the tiles/stones are installed without joint gaps and the installed tiles/ stones are unable to accommodate the movements, as a result, debonding and popping up occurs.

What makes the tiles/stones to move?

The tiles / stones fixed on the wall/floor will also make movement due to many reasons. The following are a few reasons which make the installed tiles/stones to move:-

Physical Building Movement: This is the movement of vibration and deflection caused by the process of installation of other building application / materials. This type of movement is the most common and will lead to failure if the proper measures are not implemented. 

Shrinkage of Concrete / Mortar: Shrinkage of concrete/mortar occurs during the process of curing and hydration. In today’s world, fast track construction has become normal to install tiles/stones over new concrete/mortar surfaces that may not undergo all the shrinkage that it shall. In many cases, you may see tiles / stones tented up over new installations. The continuous shrinkage of concrete takes place; as a result the gap is formed in between tiles / stones and concrete / mortar.

Thermal Movement: The thermal movement includes temperature fluctuations and changes in the environment. It is easy to understand in case of exterior applications. All installed tiles / stones are subjected to the continuous cycle of cooling and heating systems, that heat and cool the air. Moving air across the installation will cause the temperature to fluctuate and results in movement.

In exteriors, imagine an installation exposed to the sun, these installations can reach surface temperatures up to 140°F (60°C). If a quick rain shower comes and douses the installation with cool rain. In this instance, the surface temperature will drop to 70°F (21°C) within a few seconds. This type of stress needs to be accommodated by joints between the tiles / stones or else, debonding occurs. Interior installations that have skylights or area surrounded by windows and glass doors needs to be treated as exterior applications.

Moisture: In some cases, the finish material used shall absorb moisture due to its porosity. Over time, this absorption of moisture shall cause growth in the finish material. This growth can lead to loss of bond, if place is not available to accommodate movement.

Dissimilar Building Materials: The use of dissimilar materials in the construction is unavoidable and this leads to dissimilar joints. There will be always movement in between the two different building materials, if they are not treated well, this movement will transfer to the surface where tiles/ and stones are present.

Is the paper joint is not enough?

If we install the tiles / stones side by side, allowed to cure and dry for 24 hrs. After that, it needs the sealing of joints. For any material, used to grout the joint gap, shall need some surface to adhere strongly, so that it avoids the penetration of water, acid and other contaminants to the substrate on which the tiles / stones are installed. But, in case of paper joints the surface of adhesion is very small and the provided grout material will goes off making the place for the contaminants. These contaminants will spread around the edges of the tiles creating unhygienic surface all over the installation.In all the above mentioned cases, it is best honour to provide joint gaps between the tiles/ stones, so that it can accommodate the movements. What if, we provide the paper joint i.e. installing the tiles/ stones just side by side?   

Whatever the material which has been used as grout for provided paper joint, will definitely fails within a short period and causes the effect as shown in the photos. The weak paper joints will show the way to dirt, moisture, chemicals and other contaminants to get inside the substrate from the top and may causes weakness in the substrate.

In order to avoid the failure of substrate and also to increase the durability of the tiles / stones, it is strongly recommended to provide the minimum joint of 2 mm between the tiles / stones and grouted with proper recommended grouts.

Other uses of tile joint grouting:

If in case of any problem and tile / stone needs to be removed and re-fitted with new. The process will be every easy. 

Tile and stone joints will avoid the cracks extension and avoid the damages to the adjacent tile & stone.

Hides the the imperfection of tile & stone edges.

Improves the look, beauty/handsomeness, and appearance…

Accommodates the movement.

Provides the easy cleanable surface, hence no chance of place to mould growth.

Many thanks to google.com, doc4242, dindoc, from where the details have been collected.