GB2595749A

GB2595749A - A floor system

Info

Publication number: GB2595749A
Application number: GB2019491.6A
Authority: GB
Inventors: Banks Nigel; Cowell James; Jowett Mark; O'donoghue Patrick; Sopala Mark
Original assignee: Ilke Homes Ltd
Current assignee: Ilke Homes Ltd
Priority date: 2020-12-10
Filing date: 2020-12-10
Publication date: 2021-12-08
Anticipated expiration: 2040-12-10
Also published as: GB2595749B; GB202019491D0

Abstract

The present application describes a floor system (100) for a modular building, comprising a main frame (102) for supporting a floor thereon and comprising a plurality of elongate frame members; a first panel assembly (110) attached to each outer face of the main frame defined by respective ones of the frame members, wherein each first panel assembly comprises a lower elongate support member (111) for engagement with a respective one of a plurality of spaced apart support pads for supporting the building; and a second panel assembly (130) coupled to each outer face of each first panel assembly, wherein a lower surface of each second panel assembly is vertically offset above a lower surface of each first panel assembly to thereby define a secondary void (162) below each second panel assembly in fluid communication with a primary void (160) located under the floor. This allows air circulation between the subfloor void and wall cavities. A method of installing a building including such a floor system is also described.

Description

A FLOOR SYSTEM

The present invention relates to a floor system for a building and in particular, but not exclusively, to a floor system for a modular building.

The use of prefabricated sections or modules for assembling an overall building structure is now commonplace, particularly in the modular building industry. Modular buildings have many different single or multi-storey applications, including domestic dwellings, commercial offices, school, hospitals, military housing, and the like. The buildings are around 60-90% completed off-site in a factory-controlled environment, and transported and assembled at the final building site. This can comprise the entire building or be components or subassemblies of larger structures to be assembled on-site. In many cases, modular contractors work with traditional general contractors to exploit the resources and advantages of each type of construction.

Completed modules are transported to the building site and assembled by crane.

A typical construction of a modular section includes a number of vertically oriented outer wall frame assemblies attached to both a horizontally oriented base or floor frame assembly and a horizontally oriented ceiling frame assembly. Vertically oriented inner wall frame assemblies are also attached to the base and ceiling frame assemblies to define a desired internal room layout of the modular structure. The frame assemblies typically comprise steel C-sections and the wall frame assemblies are typically bolted and screwed to the base and ceiling frame assemblies.

Apertures are defined in the frame assemblies for the installation of correspondingly 25 sized and shaped windows and doors.

To enable the full benefits of mass production, such as the use of production lines and automation, without requiring significant complexity of machines, standardisation of components is required. As such, common structural frame assemblies are typically used for modular building fabrication and construction.

The ground floor assembly of a modular building typically includes a steel frame suitable for supporting the wall assemblies etc. above. The frame is typically supported on spaced apart concrete foundation pads to provide a cavity below the frame in between the pads. However, corrosion of the floor frame by moisture becoming trapped and/or rising from below ground is common and over time undesirably compromises the integrity of the structure. Condensation accumulating on the inner and outer surfaces of the steel framework is also commonplace, particularly in cold temperatures, which further encourages corrosion.

It is an aim of certain embodiments of the present invention to provide a floor system for a modular building which is configured to minimise corrosion by moisture below ground level and extend the minimum structural life of the floor system from the current standard of 60 years to 100 years.

According to a first aspect of the present invention there is provided a floor system for a modular building, comprising: a main frame for supporting a floor thereon and comprising a plurality of 15 elongate frame members; a first panel assembly attached to each outer face of the main frame defined by respective ones of the frame members, wherein each first panel assembly comprises a lower elongate support member for engagement with a respective one of a plurality of spaced apart support pads for supporting the building; and a second panel assembly coupled to each outer face of each first panel assembly, wherein a lower surface of each second panel assembly is vertically offset above a lower surface of each first panel assembly to thereby define a secondary void below each second panel assembly in fluid communication with a primary void located under the floor.

Optionally, each second panel assembly is spaced apart from the first panel assembly to define a cavity therebetween.

Optionally, each second panel assembly is spaced apart from the first panel 30 assembly by at least one spacer element attached to the first panel assembly.

Optionally, each second panel assembly comprises an elongate support member extending along its lower surface and across the width of the cavity.

Optionally, the elongate support member comprises a horizontally oriented web and a pair of opposed vertically oriented flanges.

Optionally, the web comprises a plurality of apertures along its length.

Optionally, the second panel assembly comprises an insulation panel supported by the elongate support member.

Optionally, the second panel assembly comprises a layer of brick slips bonded to an outer face of the insulation panel.

Optionally, the second panel assembly comprises bitumen paint applied to an outer face of the brick slips at below ground level.

Optionally, the first panel assembly comprises an upper elongate member opposed to the first elongate member for supporting a floor.

Optionally, a vapour control layer is disposed between the floor and the upper elongate member.

Optionally, the first panel assembly comprises insulation between the upper and lower elongate members.

Optionally, the system comprises a cement particle board attached to an outer face of each first panel assembly and extending from an upper region thereof towards a lower region.

Optionally, the cement particle board terminates before the lower region.

Optionally, the system comprises a damp proof membrane located on the cement particle board and extending downwardly to wrap around the lower region of the lower elongate member.

Optionally, the system comprises a breather membrane located on the damp proof membrane and optionally wraps around the lower region of the lower elongate member.

Optionally, the system comprises insulation board attached to the lower surface of the elongate frame members.

Optionally, the system comprises floor board attached to the upper surface of the elongate frame members, the first panel assembly and the second panel assembly.

According to a second aspect of the present invention there is provided a building comprising a floor system according to the first aspect of the present invention.

Optionally, the building comprises a plinth for supporting a plurality of paving slabs around the building, wherein the plinth extends upwardly from the ground to define a substantially vertically oriented inner face spaced apart by a predetermined distance from an outer face of the second panel assembly.

Optionally, the predetermined distance is around 50mm.

According to a third aspect of the present invention there is provided a method of installing a building, comprising: lowering a preassembled floor system according to any of claims 1 to 18 on to spaced apart support pads to define a primary void below the floor system, wherein an underside of a respective one of the first panel assemblies of the floor system engages with an upper surface of a corresponding one of the support pads, and wherein a secondary void is provided on an outer side of the first panel assembly and under the second panel assembly of the floor system.

Optionally, the method comprises: constructing a plinth for supporting a plurality of paving slabs around the building, wherein the plinth extends upwardly from the ground to define a substantially vertically oriented inner face spaced apart by a predetermined distance from an outer face of the second panel assembly.

Optionally, the method comprises using the outer face of the second panel assembly as a datum to construct the plinth.

Description of the Drawings

Certain embodiments of the present invention will now be described with reference 10 to the accompanying drawings in which: Figure 1 illustrates a cross sectional view of a floor system according to certain embodiments of the present invention.

Detailed Description

As illustrated in Figure 1, a floor system 100 according to certain embodiments of the present invention for a modular building includes a galvanised steel frame 102 formed from spaced apart joist members extending between longitudinal side members. Two layers of mineral fibre insulation 104 are provided between the joist members. The steel frame 102 supports a 22mm chipboard floor deck 105 and a vapour control layer 106 is located therebetween. A 50mm polyisocyanurate (RR) insulation board 108 is mounted to the underside of the steel frame, A first panel assembly 110 is secured to a corresponding outer face of the steel frame 102 by suitable fixings, such as bolts or self-tapping screws for example. The first panel assembly 110 includes upper and lower C-section elongate steel members 111 defining the upper and lower boundaries of the assembly and spaced apart, vertically oriented stud members (not shown) extending therebetween. The first panel assembly 110 may terminate at floor level, as illustrated, and support a threshold transition piece 132 to provide level access through a door, for example. Alternatively, the first panel assembly 110 may extend vertically upwardly beyond floor level to provide a wall panel assembly extending up to a ceiling.

The first panel assembly 110 includes mineral wool insulation 112, aptly in the form of loatts' or panels, between the stud members thereof. Cement particle board (CPB) 114 is secured to the outer face of the first panel assembly 110 to extend from its upper edge downwardly to its lower edge, i.e. full height. Alternatively, the CPB may terminate slightly before the lower edge by around 10mm, for example, to prevent it "grounding" on the foundation pads described further below. Where the first panel assembly is a wall assembly, the CPB extends around 300-600mm up the outer face of the first panel assembly. The remaining height of the wall panel assembly is covered with oriented strand board (OSB) or a Gypsumr" based particle board having a thickness of 12.5 to 15mm. A high-density polyethylene film 116 with a self-adhesive backing, such as RIW SbeetsealTM tanking sheet with a bitumen/rubber self-adhesive layer, is applied to the outer face of the CPB and onto the OSB and laps under the lower edge thereof to extend under and around the lower steel C-section of the first panel assembly 110. The polyethylene film acts as a first water-and water vapour-proof barrier to protect the steel below ground level.

A breather membrane 118 is located over the OSB hoard and laps over the polyethylene film layer 116 to provide a second water-and water vapour-proof barrier to protect the steel and sheathing board above ground level.

At least one elongate spacer element 121, such as a timber batten, is located on the breather membrane 118 and secured to the cement board 114. The or each batten is around 15mm thick and is horizontally oriented. Alternatively, a plurality of vertically oriented and spaced apart, parallel timber battens may be provided. Where the first panel assembly 110 is a full wall assembly, the vertical battens would be much longer to extend the height of the wall assembly.

Expanded polystyrene (EPS) board 120 having a thickness of around 120mm is secured to the timber batten's to thereby define a cavity 122 between the EPS board and the breather membrane 118. The cavity 122 acts as a drainage cavity to minimise the build-up of moisture, such as condensation, on the outer face of the first panel assembly 110 and to allow any condensation or moisture that has accumulated therein to run downwardly under the influence of gravity and out of the cavity. Aptly, a perforated aluminium 'starter track: 124 is located along the bottom region of the EPS board 120 to support the same in position, wherein one of the two vertically oriented flanges of the C-section extends up the outer face of EPS board and the other one of the two vertically oriented flanges of The starter track extends partially up the breather membrane 118. The substantially horizontal web portion of the starter track thereby extends across the bottom of the cavity to partially close it oft whilst being perforated to allow moisture to escape. The starter track 124 aptly includes around 1 Omm perforation holes in the web portion thereof and is fixed by its inner flange to the cement particle board 114.

Rows of brick slips 126 are adhered to the outer face of the EPS board 120 and pointed using a suitable pointing mortar. Bitumen paint 128 is applied to the outer faces of the brick slips below ground level. The EPS board 120, starter track 124, and brick slips 126 thereby provide a second panel assembly 130 spaced apart from the first panel assembly 110 by the battens to define the cavity therebetween A marine ply threshold board 132 is installed over the first and second panel assemblies 110,130 to provide support for a door frame 134 and an aluminium threshold strip 136 extending across the door threshold. The marine ply board 132 is aptly wrapped in a damp proof membrane, such as RIW sheetseal, Where a door is not present, the second panel assembly 130 extends upwardly beyond the floor to form a second wall panel assembly and the brick slips extend up the outer face of the EPS board 120 thereof.

As illustrated in Figure 1, during installation, the lower floor including the floor system 100 of a dwelling to be constructed is lowered by crane on to preformed and spaced apart concrete pads 150. The under-surface of the first panel assembly 110 engages with the upper support surface of a corresponding pad 150 which is protected by another damp-proof membrane, such as RIW sheetseal. The pads provide a primary ventilated void 160 beneath the floor system through which air can flow to minimise/prevent the build-up of moisture on the steel frame. A secondary void 162 is also provided on the outer side of the first panel assembly 110 and under the second panel assembly 130.

The outer face of each outermost concrete pad 150 is used as a datum when lowering the ground floor construction on to the pads such that the outer face of the brick slips of the second panel assembly 130 vertically align with the outer face of the outermost concrete pads. A brick plinth 170 is then buiit up around the building structure using the outer face of each outermost concrete pad 150 as an initial datum followed by the outer face of the brick slips of the second panel assembly 130 as a Thither datum to ensure a gap 172 of at least around 50mm is provided between the brick plinth and the floor system 100. This ensures the secondary void 162, and in turn the primary void 160, is well ventilated. The gap is at least around 50mm to prevenl any debris, such as leaves of the like, becoming stuck, building up, and blocking the gap and in turn holding moisture against the outer surface of the brick slips and preventing airflow through the primary and secondary voids 160,162.

Paving slabs are laid on the brick plinth and around the structure to be spaced around 10mm therefrom and to fall away from the structure to ensure water run-off.

Certain embodiments of the present invention therefore provide a floor system for a modular building which is protected from corrosion by any moisture coming up through the foundations. The floor system is configured to ensure a well-ventilated void is maintained under and around the structure. The floor system is also configured to provide a datum for efficient and accurate construction of a brick plinth relative to the building structure to ensure a sufficient and uniform gap is provided between the plinth and the building structure to allow for efficient ventilation below the floor system.

Claims

Claims 1. A floor system for a modular building, comprising: a main frame for supporting a floor thereon and comprising a plurality of elongate frame members; a first panel assembly attached to each outer face of the main frame defined by respective ones of the frame members, wherein each first panel assembly comprises a lower elongate support member for engagement with a respective one of a plurality of spaced apart support pads for supporting the building; and a second panel assembly coupled to each outer face of each first panel assembly, wherein a lower surface of each second panel assembly is vertically offset above a lower surface of each first panel assembly to thereby define a secondary void below each second panel assembly in fluid communication with a primary void located under the floor.
2. The floor system according to claim 1, wherein each second panel assembly is spaced apart from the first panel assembly to define a cavity therebetween.
3. The floor system according to claim 2, wherein each second panel assembly is spaced apart from the first panel assembly by at least one spacer element attached to the first panel assembly.
4. The floor system according to claim 2 or 3, wherein each second panel assembly comprises an elongate support member extending along its lower surface and across the width of the cavity.
5. The floor system according to claim 4, wherein the elongate support member comprises a horizontally oriented web and a pair of opposed vertically oriented flanges.
6. The floor system according to claim 5, wherein the web comprises a plurality of apertures along its length.
7. The floor system according to any of claims 4 to 6, wherein the second panel assembly comprises an insulation panel supported by the elongate support member.
8. The floor system according to claim 7, wherein the second panel assembly comprises a layer of brick slips bonded to an outer face of the insulation panel.
9. The floor system according to claim 8, wherein the second panel assembly comprises bitumen paint applied to an outer face of the brick slips at below ground level.
10. The floor system according to any preceding claim, wherein the first panel assembly comprises an upper elongate member opposed to the first elongate member for supporting a floor.
11. The floor system according to claim 10, wherein a vapour control layer is disposed between the floor and the upper elongate member.
12. The floor system according to claim 10 or 11, wherein the first panel assembly comprises insulation between the upper and lower elongate members.
13. The floor system according to any preceding claim, comprising a cement particle board attached to an outer face of each first panel assembly and extending from an upper region thereof towards a lower region.
14. The floor system according to claim 13, wherein the cement particle board terminates before the lower region.
15. The floor system according to any preceding claim, comprising a damp proof membrane located on the cement particle board and extending downwardly to wrap around the lower region of the lower elongate member.
16. The floor system according to claim 15, comprising a breather membrane located on the damp proof membrane and optionally wraps around the lower region of the lower elongate member.
The floor system according to any preceding claim, comprising insulation board attached to the lower surface of the elongate frame members.
The floor system according to any preceding claim, comprising floor board attached to the upper surface of the elongate frame members, the first panel assembly and the second panel assembly.
A building comprising a floor system according to any preceding claim.
The building according to claim 19, comprising a plinth for supporting a plurality of paving slabs around the building, wherein the plinth extends upwardly from the ground to define a substantially vertically oriented inner face spaced apart by a predetermined distance from an outer face of the second panel assembly.
The building according to claim 20, wherein the predetermined distance is around 50mm.
A method of installing a building, comprising: lowering a preassembled floor system according to any of claims 1 to 18 on to spaced apart support pads to define a primary void below the floor system, wherein an underside of a respective one of the first panel assemblies of the floor system engages with an upper surface of a corresponding one of the support pads, and wherein a secondary void is provided on an outer side of the first panel assembly and under the second panel assembly of the floor system.
23. The method according to claim 22, comprising: constructing a plinth for supporting a plurality of paving slabs around the building, wherein the plinth extends upwardly from the ground to define a substantially vertically oriented inner face spaced apart by a predetermined distance from an outer face of the second panel assembly.
24. The method according to claim 23, comprising using the outer face of the second panel assembly as a datum to construct the plinth. 17. 18. 19. 20. 21. 22.