Claims:We claim:

1. An improved building-envelop for constructing new generation buildings, comprising:

• a plurality of building blocks made of cellular light-weight concrete (CLC) containing nano-admixture;

• said building blocks forming various building components for making the building-envelop according to the preconfigured building layout;

• a plurality of layers of coatings applied to the external sides of said building-envelop; and

• another plurality of layers of coatings applied to the internal sides of said building-envelop;

wherein said nano admixture is mixed on-site or off-site to be thoroughly impregnated into said cellular light-weight concrete (CLC) to form a cement matrix composite having a higher flexural strength and compressive strength and increased interfacial interaction therebetween and thus reduces the crack propagation in said cement matrix used as a cement composite for making the building-envelop for new generation buildings.

2. Building-envelop as claimed in claim 1, wherein said nano admixture comprises surface treated carbon nanotubes (CNT) thoroughly mixed into said cellular light-weight concrete (CLC) and impregnated therein to form a cement matrix composite having a higher flexural strength.

3. Building-envelop as claimed in claim 1, wherein said nano admixture comprise surface treated carbon nanotubes (CNT) thoroughly mixed into said cellular light-weight concrete (CLC) and impregnated therein to form a cement matrix composite having a compressive strength.

4. Building-envelop as claimed in claim 1, wherein said nano admixture comprises nano materials thoroughly mixed into said cellular light-weight concrete (CLC) and impregnated therein to form a cement matrix composite having an increased interfacial interaction therebetween to reduce crack propagation in said cement composite to be used for making said improved building-envelop for new generation buildings.

5. Building-envelop as claimed in anyone of the claims 1 to 4, wherein said building-envelop coated with said plurality of layers comprising:

• external single coating of nano weather thermal insulation primer;

• two coatings of nano heat insulation weather resistance putty applied on said primer coated external side;

• two coatings of nano weather thermal insulation paint applied externally to complete said building-envelop from outside; and

• single coating of nano primer applied inside said building-envelop;

• two coatings of nano heat insulation putty applied on said primer coated internal side;

• two coatings of nano heat insulation finish paint applied internally to complete said building-envelop from inside;

wherein each layer of coating is dried for a predetermined time to ensure proper adhesion thereof to said building-envelop or said previously coated external or internal side thereof in order to obtain a predefined low thermal conductivity in said building-envelop for new generation buildings.

6. Building-envelop as claimed in anyone of the claims 1 to 5, wherein said nano admixture comprises surface treated carbon nanotubes (CNT) mixed with nanosized calcium (Ca), iron (Fe), silicon (Si), zinc-oxide (ZnO).

7. Building-envelop as claimed in anyone of the claims 1 to 6, wherein said building-envelop exhibits low thermal conduction having a U-value in the range of 1 to 1.5 W/m2K.

8. Building-envelop as claimed in anyone of the claims 1 to 7, wherein said building-envelop exhibits resistant to fire for approximately 2 to 3 hours.
9. A method for constructing a low-conductivity building-envelop as claimed in anyone of the claims 1 to 8, wherein said method comprises the steps of:

• constructing a building-envelop using a plurality of Cellular Light-weight Concrete (CLC) blocks incorporated with said nano-admixture and joined together according to the desired building layout;

• externally coating a single layer of nano weather thermal insulation primer coating on said building-envelop;

• applying two layers of a nano heat insulation weather resistance putty coatings on said primer coated external side of said building-envelop;

• applying two layers of a nano weather thermal insulation paint on said putty coated external side of said building-envelop to complete said building-envelop from outside; and

• applying a single layer of a nano primer coating inside said building-envelop;

• applying two layers of a nano heat insulation putty coatings on said primer coated internal side; and

• applying two layers of a nano heat insulation finish paint coatings on said putty coated internal side of said building-envelop to complete said building-envelop from inside;

wherein each layer of aforesaid coatings is dried for a predetermined time to ensure proper adhesion thereof to said building-envelop or said previously coated external or internal side thereof in order to obtain a predefined low thermal conductivity in said building-envelop for new generation buildings.

10. A method for constructing an improved building-envelop for new generation buildings, comprising:

• thoroughly mixing a nano-admixture consisting of surface treated carbon nanotubes (CNT) with nanosized calcium (Ca), iron (Fe), silicon (Si), zinc-oxide (ZnO) on-site or off-site into Cellular Light-weight Concrete (CLC) to form a cement matrix composite;

• making a plurality of building blocks out of said cement matrix;

• making various building components, e.g. wall/s etc. for making said building-envelop according to the preconfigured building layout;

• externally coating a single layer of nano weather thermal insulation primer coating on said building-envelop;

• applying two layers of a nano heat insulation weather resistance putty coatings on said primer coated external side of said building-envelop;

• applying two layers of a nano weather thermal insulation paint on said putty coated external side of said building-envelop to complete said building-envelop from outside; and

• applying a single layer of a nano primer coating inside said building-envelop;

• applying two layers of a nano heat insulation putty coatings on said primer coated internal side; and

• applying two layers of a nano heat insulation finish paint coatings on said putty coated internal side of said building-envelop to complete said building-envelop from inside;

wherein each layer of aforesaid coatings is dried for a predetermined time to ensure proper adhesion thereof to said building-envelop or said previously coated external or internal side thereof in order to obtain a predefined low thermal conductivity in said building-envelop for constructing new generation buildings.

Digitally Signed.

Dated: this 28th day of December 2018. (SANJAY KESHARWANI)
APPLICANTS’ PATENT AGENT
For: MAHINDRA LIFESPACE DEVELOPERS LIMITED. , Description:FIELD OF INVENTION

The present invention relates to modern buildings being constructed by the real estate sector. In particular, the present invention relates to improved envelops for buildings. More particularly, the present invention relates to a low thermal conductivity envelop for such new generation buildings.

BACKGROUND OF THE INVENTION

The conventional building-envelops normally consist of red clay bricks, precast solid cement concrete blocks or precast hollow concrete blocks made of a mixture of cement, fine gravel and sand. A semi-finished building-envelop is made by using a reinforced structure suitably partitioned by such precast solid or hollow cement-concrete blocks according to the desired and sanctioned building layout. Subsequently a thin coating of plaster composed of mortar including cement and sand is externally applied on such semi-finished building-envelop. Similarly, in prefabricated building structures, the building-envelop components are similarly finished by externally applying a thin coating of plaster composed of mortar including cement and sand. Therefore, the building-envelop or the components thereof normally have substantial weight and their supporting structures should be designed to be quite sturdy. Moreover, the external plaster also requires sufficient time to dry to finish such conventional buildings.

PRIOR ART

As discussed above, the building-envelops are quite heavy and also require costly materials to be used for making cement-concrete solid or hollow blocks. Further, due to higher weight of the supporting/reinforcing structures, these are also required to be made heavy and thus they become expensive. In recent times, Cellular Lightweight Concrete (CLC) is often used for making these building blocks to make the building structures lighter in weight.

DISADVANTAGES WITH THE PRIOR ART

The building-envelop made of red clay bricks is not an environment friendly product. Because most fertile part of soil i.e. top soil is being used for making these red clay bricks and this causes substantial environmental degradation. Moreover, a large amount of heat is also required for making these red bricks, which also requires huge volume of wood or other heat releasing fossil fuels. The major disadvantage even with solid or hollow cement-concrete blocks is that these are heavier in weight and significantly increase the dead load on the building structure. In addition, these blocks are not thermally efficient enough.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

The object of the present invention is to provide a building-envelop having a lower thermal conductivity value in comparison to the building-envelops presently available in the market.

The object of the present invention is to provide a building-envelop component, which is light-weight, thus reduces the dead load on building structures and is thereby more economical to make.

Another object of the present invention is to provide a building-envelop, which has low water absorption value and thus prevents any possibility of water seepage therethrough during rains.

A further object of the present invention is to provide a building-envelop, which improves worker’s productivity and is thus cost-effective to make.

A still further object of the present invention is to provide a building-envelop, which has excellent flexural and compressive strength.
A further object of the present invention is to provide a building-envelop, which effectively hinders any crack propagation in the cement composites being used in modern building structures.

These and other objects and advantages of the present invention will become more apparent from the following description when read with the accompanying figures of drawing, which are, however, not intended to limit the scope of the present invention in any way.

DESCRIPTION OF THE INVENTION

In order to achieve the above-mentioned objects of the present invention and to overcome the disadvantages associated with the building-envelop and their components presently available in the market, in accordance with the present invention, the inventors have developed a low thermal conductivity envelop for new generation buildings.

Accordingly, a lightweight building-envelope component has been developed, which does not require any mortar or cement and sand plaster to be applied externally. This also leads to a new method of producing a low-cost building-envelop component.

At present, Cellular Lightweight Concrete (CLC) is used for making building blocks, which are prone to water seepage therethrough. Therefore, for improving the water impermeability of the building blocks made of CLC, in accordance with the present invention, a nano admixture containing carbon nanotubes (CNT) is added to the mixture composition.

The use of surface treated multi-walled carbon nanotubes increases the flexural strength, compressive strength and failure strain of the cement matrix composite. This also enhances the interfacial interaction between CNT and Calcium-Silicate- Hydrate (C-H-S) gel, which produces high bonding strength between the reinforcing elements or reinforcement in general and the cement matrix used.
Thereby, crack propagation in cement composites used in modern building structures is effectively checked. CNT also bridges across voids and cracks in the building blocks and ultimately helps in load transfer in case of any undue tension therein. With this construction and method of production, a less impervious, light-weight building-envelop component is successfully obtained.

These light-weight components are used for making the building-envelop in accordance with the invention. The walls constructed by these improved building blocks are then coated with weather and thermal resistant nano putty and nano paint, which converts the entire building-envelope composition into a weather resistant building-envelope with better heat insulation than the conventional brick and concrete walls or constructions using existing solid or hollow cement-concrete blocks for making buildings.

SUMMARY OF THE INVENTION

In accordance with an embodiment of the present invention, there is provided an improved building-envelop for constructing new generation buildings, comprising:
• a plurality of building blocks made of cellular light-weight concrete (CLC) containing nano-admixture;
• the building blocks forming various building components for making the building-envelop according to the preconfigured building layout;
• a plurality of layers of coatings applied to the external sides of the building-envelop; and
• another plurality of layers of coatings applied to the internal sides of the building-envelop;

wherein the nano admixture is mixed on-site or off-site to be thoroughly impregnated into the cellular light-weight concrete (CLC) to form a cement matrix composite having a higher flexural strength and compressive strength and increased interfacial interaction therebetween and thus reduces the crack propagation in the cement matrix used as a cement composite for making the building-envelop for new generation buildings.
Typically, the nano admixture comprises surface treated carbon nanotubes (CNT) thoroughly mixed into the cellular light-weight concrete (CLC) and impregnated therein to form a cement matrix composite having a higher flexural strength.

Typically, the nano admixture comprise surface treated carbon nanotubes (CNT) thoroughly mixed into the cellular light-weight concrete (CLC) and impregnated therein to form a cement matrix composite having a compressive strength.

Typically, the nano admixture comprises nano materials thoroughly mixed into the cellular light-weight concrete (CLC) and impregnated therein to form a cement matrix composite having an increased interfacial interaction therebetween to reduce crack propagation in the cement composite to be used for making the improved building-envelop for new generation buildings.

Typically, the building-envelop coated with the plurality of layers comprising:

• external single coating of nano weather thermal insulation primer;

• two coatings of nano heat insulation weather resistance putty applied on the primer coated external side;

• two coatings of nano weather thermal insulation paint applied externally to complete the building-envelop from outside; and

• single coating of nano primer applied inside the building-envelop;

• two coatings of nano heat insulation putty applied on the primer coated internal side;

• two coatings of nano heat insulation finish paint applied internally to complete the building-envelop from inside;

wherein each layer of coating is dried for a predetermined time to ensure proper adhesion thereof to the building-envelop or the previously coated external or internal side thereof in order to obtain a predefined low thermal conductivity in the building-envelop for new generation buildings.
Typically, the nano admixture comprises surface treated carbon nanotubes (CNT) mixed with nanosized calcium (Ca), iron (Fe), silicon (Si), zinc-oxide (ZnO).

Typically, the building-envelop exhibits low thermal conduction having a U-value in the range of 1 to 1.5 W/m2K.

Typically, the building-envelop exhibits resistant to fire for approximately 2 to 3 hours.

In accordance with the present invention, there is also provided a method for constructing a low-conductivity building-envelop, the method comprises the steps of:

• constructing a building-envelop using a plurality of Cellular Light-weight Concrete (CLC) blocks incorporated with the nano-admixture and joined together according to the desired building layout;

• externally coating a single layer of nano weather thermal insulation primer coating on the building-envelop;

• applying two layers of a nano heat insulation weather resistance putty coatings on the primer coated external side of the building-envelop;

• applying two layers of a nano weather thermal insulation paint on the putty coated external side of the building-envelop to complete the building-envelop from outside; and

• applying a single layer of a nano primer coating inside the building-envelop;

• applying two layers of a nano heat insulation putty coatings on the primer coated internal side; and

• applying two layers of a nano heat insulation finish paint coatings on the putty coated internal side of the building-envelop to complete the building-envelop from inside;

wherein each layer of aforesaid coatings is dried for a predetermined time to ensure proper adhesion thereof to the building-envelop or the previously coated external or internal side thereof in order to obtain a predefined low thermal conductivity in the building-envelop for new generation buildings.

In an embodiment of the present invention, there is provided another method for constructing an improved building-envelop for new generation buildings, comprising:

• thoroughly mixing a nano-admixture consisting of surface treated carbon nanotubes (CNT) with nanosized calcium (Ca), iron (Fe), silicon (Si), zinc-oxide (ZnO) on-site or off-site into Cellular Light-weight Concrete (CLC) to form a cement matrix composite;

• making a plurality of building blocks out of the cement matrix;

• making various building components, e.g. wall/s etc. for making the building-envelop according to the preconfigured building layout;

• externally coating a single layer of nano weather thermal insulation primer coating on the building-envelop;

• applying two layers of a nano heat insulation weather resistance putty coatings on the primer coated external side of the building-envelop;

• applying two layers of a nano weather thermal insulation paint on the putty coated external side of the building-envelop to complete the building-envelop from outside; and

• applying a single layer of a nano primer coating inside the building-envelop;

• applying two layers of a nano heat insulation putty coatings on the primer coated internal side; and

• applying two layers of a nano heat insulation finish paint coatings on the putty coated internal side of the building-envelop to complete the building-envelop from inside;

wherein each layer of aforesaid coatings is dried for a predetermined time to ensure proper adhesion thereof to the building-envelop or the previously coated external or internal side thereof in order to obtain a predefined low thermal conductivity in the building-envelop for constructing new generation buildings.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described with reference to the accompanying drawings, in which:

Figure 1A shows a portion of the wall of a new generation building-envelope produced in accordance with the present invention.

Figure 1B shows a cross-sectional view of the wall-portion shown in Fig. 1A.

Figure 2 shows a flow chart of the method adopted for producing the building-envelope in accordance with the present invention.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Figure 1A shows a portion of the wall of a new generation building-envelope produced in accordance with the present invention. The external side thereof is represented by reference numeral 10 and the internal side by 20. A section plane P-Q-R-S is also marked, which is used to show the cross-sectional view of this wall-portion in Figure 1B described further below.

Figure 1B shows a cross-sectional view of the wall-portion shown in Figure 1A which clearly shows various constituent layers applied on the wall portion made of a plurality of Cellular Lightweight Concrete (CLC) blocks incorporated with nano-admixture used for making a low thermal conductivity envelop for new generation buildings configured in accordance with the present invention. As shown in Figure 1A, the external side of this wall-portion is marked 10 and internal side is marked 20. The nano-admixture is either prepared either on-site or off-site, i.e. in concerned industry. Subsequently this nano-admixture is utilized for producing these CLC blocks. A plurality of these CNT impregnated CLC blocks are then placed for making the wall-portion shown in Figure 1A at the desired location as per the sanctioned/desired layout of the building-envelop. After the construction of the required building-envelop 100, a single coat of nano weather, thermal insulation primer 12 is applied on the external side 10 of the building-envelop 100 and it is left to dry for a predetermined time. Thereafter, two coats of nano heat insulation weather resistance putty 14 is applied over the aforesaid nano weather thermal insulation primer coated external side and it is left to dry for a predetermined time. Finally, two coats of nano weather thermal insulation paint 16 is applied to externally to complete the low thermal conductivity building-envelop and it is left to dry for a predetermined time. Now, a single coat of nano primer 22 is applied from the inside of the building-envelop 100 and left to dry for a predetermined time. Thereafter, two coats of nano heat insulation internal putty 24 is applied and it is left to dry for a predetermined time. Finally, two coats of nano heat insulation internal finish paint 26 are applied on the inside and it is left to dry for completing the finished low thermal conductivity building-envelop configure in accordance with the invention for new generation buildings, a wall-portion of which is exemplarily shown in Fig. 1A.

Figure 2 shows a flow chart of the method adopted for producing the low thermal conductivity envelop for new generation buildings, a wall-portion of which is exemplarily shown in Figure 1. Initially, the CLC blocks are produced on-site or in a manufacturing plant off-site by using nano admixture. These CLC blocks are then brought to the site for construction of the building-envelop. According to the building-envelop layout, a plurality of CLC blocks are placed for constructing wall/s or component/s of the building-envelop according to the invention. Subsequently, these walls or components of the building-envelops are externally coated in sequence, first with a single coat of nano weather, thermal insulation primer, then two coats of nano heat insulation weather resistance putty and finally two coats of nano weather thermal insulation paint to externally complete the low thermal conductivity building-envelop. Similarly, a sequential internal coating is carried out by first applying a single coat of nano primer, then two coats of nano heat insulation putty and finally two coats of nano heat insulation finishing paint to internally complete the low thermal conductivity building-envelop. It is ensured that each of the above-mentioned external or internal coats is allowed a sufficient time for drying, to ensure proper adhesion of each coat subsequently applied on the previously applied coating. This drying time can be predetermined for achieving the desired optimum performance.

As described above, this low thermal conductivity building-envelop for new generation building uses nano materials, such as Carbon Nano Tubes (CNT), Nano Ca, Fe, Si, ZnO etc. and thus it exhibits a low thermal conduction of U-value in a range of 1.061 to 1.336 W/m2K (refer to Table- I). It exhibits fire resistance for more than 2.5 hours and has an improved density and impermeability for the building-envelop. There is reduced shrinkage of the building block components. This low-conductivity building-envelop also shows an improved tensile strength, crack resistance, thereby hindering any crack propagation in the cement composited used therein. Table-I below indicates the different values applicable for U- value calculation for the building-envelop made with CLC-nanotechnology combination as discussed above:

Table-I

Wall Assembly: External to Internal U-value calculation
Layer from External to Internal Density (lb/ft3) Thickness
(micron) R-value
ft2.°F.h / BTU
Min Max
External Air Film NA - 0.15 0.17 Ashrae 90.1- 2004
External Wall Paint NA 40-60 0.2 0.35 ECBC
External Wall Primer 30-50 0.2 0.25 ECBC
External Wall Putty 1000-3000 0.30 0.45 ECBC
(Page 53)
CLC Block Section 177800-228600 2.1 2.3 ECBC
Internal Wall Putty NA 1000-3000 0.30 0.45 ECBC
(Page 53)
Internal Wall Primer 30-50 0.20 0.25 ECBC
Internal Wall Paint 40-60 0.20 0.35 ECBC
Internal Air Film - 0.60 0.78 Ashrae 90.1- 2004
Total 4.25 5.35
R- value K.m2/W 0.75 0.94
U- value W/m2.K 1.336 1.061

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

The low thermal conductivity building-envelop configured in accordance with the invention for new generation buildings has the following advantages:

• lower thermal conductivity value than conventional building-envelops plastered with mortar (cement plus sand) plaster.

• light-weight to reduce dead load on building structures and thus more economical to make.

• Low-water absorption value to prevents water seepage therethrough.
• Improves workers’ productivity and thus cost-effective to make.

• Excellent flexural and compressive strength.

• Effectively hinders crack propagation in cement composites used therein.

It is to be understood that the present invention is not limited in its application to the details of the construction and to the arrangements of the components as mentioned in the above description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, the terminologies used herein are for the purpose of description and should not be regarded as limiting.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept.

Therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

The description provided herein is purely by way of example and illustration. The various features and advantageous details are explained with reference to this non-limiting embodiment in the above description in accordance with the present invention.

The descriptions of well-known components and manufacturing and processing techniques are consciously omitted in this specification, so as not to unnecessarily obscure the specification. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Therefore, while the embodiments herein have been described in terms of preferred embodiments, the skilled person will recognize that the embodiments herein can be practiced with modification within the spirit and scope of embodiments described herein.

The skilled person can easily make innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies, assemblies and in terms of the size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.
Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to implies including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention.