GB2446451A

GB2446451A - A roof or wall oversheeting system

Info

Publication number: GB2446451A
Application number: GB0702340A
Authority: GB
Inventors: William Frank Price
Original assignee: ALASTAIR ROXBURGH PRICE; DEREK FRANK PRICE; ROBERT WILLIAM PRICE
Current assignee: ALASTAIR ROXBURGH PRICE; DEREK FRANK PRICE; ROBERT WILLIAM PRICE
Priority date: 2007-02-07
Filing date: 2007-02-07
Publication date: 2008-08-13
Anticipated expiration: 2027-02-07
Also published as: GB2446451B; GB0702340D0

Abstract

A building system comprising a plurality of structural support 3s, a first building structure 1 supported by the structural supports, and a second building structure 12 is disclosed. The building system might be a roof or wall structure. The second building structure 12 is located adjacent to the first building structure 1. The building system includes at least one support assembly 6 that supports some of the weight of the second building structure 12, and which extends through an aperture in the first building structure 1. The building system also includes a sealing means, the sealing means 16 being arranged on the support assembly to seal the aperture in the first building structure. The sealing means comprises a resilient seal 16 that is axially compressible on application of pressure in an axial direction, and is adapted to expand axially if such pressure is released, to maintain sealing of the aperture. A support assembly, and a method of repairing a building, are also disclosed.

Description

I

"Building System" The present invention relates to a building system comprising a first building structure and a second building structure located adjacent to the first building structure. The present invention also relates to a method of repairing a pre-existing building, and to a support system for a building system. The building structure may be a roof or a wall.

Industrial and commercial roofs and walls have, for approximately 30 years, used foam insulation in conjunction with profiled metal sheets or membranes, such as bitumen felt and plastic. These installations, in many cases, are now reaching the end of their life and require replacement.

Most foam insulation materials, such as polystyrene, polyurethane and polyisocyanurate will burn and, in many cases, give off toxic gases, and as such are difficult and expensive to dispose of. Therefore, foam insulation materials are largely disposed of in landfill sites, which are becoming scarce and expensive. The foam insulation materials may ultimately have to be shredded, which is even more expensive.

A further problem with conventional roofs is, if they were not recently built, they may not conform to present-day building regulations for thermal insulation. Buildings with such roofs need extra heating, which is expensive, and which also contributes to greenhouse gases and global warning, thereby damaging the environment.

According to a first aspect of the present invention, there is provided a building system comprising: a plurality of structural members; a first roof structure supported by the structural members; a second building structure located adjacent to the first building structure; and at least one support assembly that supports some of the weight of the second roof structure; wherein the support assembly is fixed to one of the structural members such that the support assembly transfers said weight of the second building structure directly to the structural member.

By "directly" it is meant that the transfer of weight occurs independently of the first building structure.

By "structural member", it is meant any member to which a roof/wall is connected, and which supports that roof/wall.

Optionally, the building structure could be a roof structure. In this case, the structural members are typically purlins, and the second roof structure is typically located above the first roof structure.

Alternatively, the building structure could be a wall structure. In this case, the structural members are typically cladding rails, and the second wall structure is typically an outer wall, whilst the first wall structure is an inner wall.

Transferring the weight of the second building structure directly to the structural member has the advantage that no, or negligible, weight is brought to rest on the first building structure, prolonging the life of the first building structure, and providing a safe building system. This is especially beneficial if the first building structure has been in use for a considerable period of time, and may be quite weak.

Another advantage is that the fixing of the support assembly to the purlin is secure and unaffected by any compression of the first building structure.

Such compression of the first building structure may be caused by the gradual compression, over a period of time, of a foam insulation component of the first building structure.

Using two building structures, one adjacent to the other, gives improved insulation of the building, both by having two barriers against heat loss, and by making it possible to incorporate insulation material into both the first and the second building structures. This benefits the environment and saves costs, because less heating of the building will be needed.

Typically, the support assembly extends through an aperture in the first building structure.

Preferably, the building system also includes a sealing means, the sealing means being arranged on the support assembly to seal the aperture in the first building structure.

Sealing the aperture has at least two benefits. Firstly, rain is prevented from entering the sealed aperture whilst the building system is being installed/constructed/repaired. Secondly, in use, the sealed aperture prevents vapour from rising from the inside of the building, through the aperture and into the roof/wall cavity, and forming condensation in the cavity.

Typically, the sealing means comprises a seal and a nut, and the seal is arranged on the support assembly between the aperture in the first building structure and the nut. Optionally, the nut is a wing nut.

Optionally, the support assembly has external screw threads and the nut has internal screw threads engaged therewith.

Preferably, the seal comprises a resilient seal that is axially compressed belween the nut and the aperture in the first building structure, such that on any release of pressure on the resilient seal by the first building structure, the resilient seal will expand to maintain sealing of the aperture.

Such embodiments have the advantage that effective sealing is maintained, even if the first building structure compresses over time.

Typically, the support assembly comprises a support means and a fixing device.

Typically, the support means is cylindrical. The support means could be a hollow or solid cylinder.

Preferably, the support means is hollow and the fixing device is located within the support means and engaged with the structural member to fix the support assembly to the structural member.

Typically, the fixing device comprises screw threads.

Preferably, the fixing device comprises a self-tapping screw. Alternatively, the fixing device could comprises a self-drilling screw or a bolt.

Preferably, the support means comprises an outer sleeve and an inner sleeve located within the outer sleeve.

With two sleeves, each of the outer and inner sleeves can have a thinner wall thickness than would otherwise be required.

Alternatively, the support means comprises a single component.

Typically, the support means comprises a plastics material.

Optionally, the support means is entirely formed from a plastics material.

Plastic is beneficial, because it is a poor conductor of heat, and as such, can contribute to the prevention of "cold bridging" in the building system.

Cold bridging is where outside temperatures are transferred to the inside of a building, by conduction through highly conductive materials, e.g. metal.

Preferably, there is no unbroken path of metal to metal contact between the structural member and the second building structure. Such embodiments help to prevent or eliminate "cold bridging".

Preferably, both the first building structure and the second building structure comprise insulation material.

According to a second aspect of the invention, there is provided a method of repairing a pre-existing building comprising a first building structure supported by structural members, comprising the steps of: supporting a second building structure adjacent to the first building structure, on at least one support assembly; and fixing the support assembly to one of the structural members such that the support assembly transfers the weight of the second building structure directly to the structural member.

Typically, the building structure comprises a roof structure. Alternatively, the building structure comprises a wall structure.

Repairing the existing building whilst retaining the first building structure eliminates the need to dispose of the first building structure (and costs thereof), and the consequent damage to the environment, e.g. through burning or dumping in a landfill site. Advantageously, any insulation material already included in the pre-existing roof or wall can remain as part of the roof/wall, saving wastage, and already providing a basic amount of insulation for the repaired and improved roof/wall.

Repairing the building by adding a second building structure adjacent to the first building structure gives the possibility of improving the insulation of the building, both by having added a further barrier against heat loss, and by providing the possibility to add further insulation material as part of the second building structure. This also benefits the environment because, with reduced heat loss, less heating of the building will be needed. Hence, this also gives a further cost saving.

Additionally, installing a second building structure without removing the first building structure is inherently less disruptive to people and processes operating in the building.

Typically, the method includes the step of making an aperture in the first building structure and connecting the support assembly to the structural member through the aperture.

Preferably, the method includes the step of sealing the aperture in the first building structure.

Optionally, the step of sealing the aperture includes: fitting a resilient seal around the support assembly; compressing the resilient seal in the axial direction against the aperture in the first building structure; and fixing the resilient seal in its compressed configuration, such that, on any release of pressure on the resilient seal by the first building structure, the resilient seal will expand to maintain sealing of the aperture.

Preferably, the method includes adding further insulation material as part of the second building structure. This further insulation material may be any insulation material, for example, mineral wool insulation.

Typically, the support assembly comprises a hollow support and a fixing device, and the method includes the steps of inserting the fixing device through the hollow support and engaging the fixing device with the structural member.

According to a third aspect of the present invention, there is provided a support system for a building system comprising: a hollow support adapted to support a building structure; and a fixing device adapted to fit within the hollow support; wherein the hollow support terminates in a lower face, and wherein the fixing device has structural member-engaging means extendible through the lower face of the hollow support.

Preferably, the support system also includes a sealing means adapted to seal an aperture in the building system.

Typically, the sealing means comprises a seal and a nut. Optionally, the nut is a wing nut.

Typically, the hollow support has external screw threads, and the nut has internal screw threads for engagement therewith.

Preferably, the seal comprises a resilient seal that is axially compressible on application of pressure in an axial direction, and adapted to expand axially if such pressure is released.

Typically, the hollow support is cylindrical.

Typically, the structural support-engaging means of the fixing device comprises screw threads.

Preferably, the fixing device comprises a self-tapping screw. Alternatively, the fixing device could comprise a self-drilling screw or a bolt.

Preferably, the hollow support comprises an outer sleeve and an inner sleeve.

Alternatively, the hollow support comprises a single sleeve.

Preferably, the hollow support comprises a plastics material.

Typically, the hollow support is entirely formed from a plastics material.

According to a fourth aspect of the present invention, there is provided a building system comprising: a plurality of structural supports; a first building structure supported by the structural supports; a second building structure located adjacent to the first building structure; and at least one support assembly that supports some of the weight of the second building structure; wherein the support assembly extends through an aperture in the first building structure, and wherein the building system also includes a sealing means, the sealing means being arranged on the support assembly to seal the aperture in the first building structure.

Typically, the sealing means comprises a seal and a nut, and the seal is arranged on the support assembly between the aperture in the first building structure and the nut. Optionally, the nut comprises a wing nut.

Typically, the support assembly has external screw threads and the nut has internal screw threads engaged therewith.

Preferably, the seal comprises a resilient seal that is axially compressed between the nut and the aperture in the first building structure, such that on any release of pressure on the resilient seal by the first building structure, the resilient seal will expand to maintain sealing of the aperture.

Such embodiments have the advantage that sealing is maintained, even if the first building structure compresses over time.

The building system of the fourth aspect of the invention may optionally include any of the features of the building system of the first aspect of the invention.

According to a fifth aspect of the present invention, there is provided a method of repairing a pre-existing building comprising a first building structure supported by structural members, comprising the steps of: making an aperture in the first building structure; fixing a support assembly to the pre-existing building; supporting a second building structure on the support assembly; and sealing the aperture in the first building structure.

Typically, the step of sealing the aperture includes: flthng a resilient seal around the support assembly; compressing the resilient seal in the axial direction against the aperture in the first building structure; and fixing the resilient seal in its compressed configuration, such that, on any release of pressure on the resilient seal by the first building structure, the resilient seal will expand to maintain sealing of the aperture.

The method of the fifth aspect of the invention can optionally include any of the steps of the method of the second aspect of the invention.

According to a sixth aspect of the present invention, there is provided a support system for a building system comprising: a support means having external screw threads; and a fixing device adapted to fix the support means to the building system; and a sealing means adapted to seal an aperture in the building system, the sealing means comprising an annular seal and a nut, the nut having internal screw threads adapted to engage the external screw threads on the support means.

Optionally, the nut is a wing nut.

The support system of the sixth aspect of the invention may optionally include any aspects of the support system of the third aspect of the invention.

For the avoidance of doubt, in embodiments according to the first, second and third aspects of the invention, a sealing means is not an essential element. In embodiments according to the fourth, fifth and sixth aspects, the weight of the second building structure being directly transferred to the structural member is not an essential element.

An embodiment of the invention will now be described, by way of example only, and with reference to the followings drawings, in which:- Fig I shows a perspective view of a roof system according to the invention, the roof system comprising a support assembly; Fig 2 shows a side view with interior detail of the roof system of Fig 1; Fig 3 shows a sectional view along the line X-X of Fig 2; Fig 4 shows a sectional view similar to Fig 3, but of a second embodiment of roof system, including a support assembly which comprises two sleeves; and Fig 5 shows a side view with interior detail of a third embodiment of roof system, including a support assembly attached at an alternative location.

Figs I to 5 relate to embodiments of the invention in which the "building structure" is a roof structure, and in which the "structural members" are purlins.

Referring to Figs I to 3, and starting from a lower end, the roof system comprises metal purlins 3 (only one shown). Supported on the purlins 3 is a first roof structure comprising an upper roof skin IA, a lower roof skin I B and foam insulation 2. The upper roof skin IA is profiled (corrugated), with ribs lAP and troughs IAT on either side of the ribs. In this embodiment, the ribs lAP are trapezoidal. The first roof structure and the metal purlins 3 comprise a pre-existing, conventional British roof.

Referring particularly to Fig 2, a circular aperture 5 is cut out of one of the ribs lAP in the upper roof skin IA. A piece of foam directly underneath the aperture 5 has been cut out of the foam insulation 2, along with a circular piece of the lower roof skin I B, to leave a cylindrical hole 4 corresponding in shape to the circular aperture 5. The circular aperture of the lower roof skin I B is preferably cut out of a raised portion of a minirib of the lower roof skin I B. Extending through the aperture 5 and cylindrical hole 4 is a support assembly. The support assembly comprises a hollow cylindrical plastic sleeve 6 (a support means) and a fixing device.

The sleeve 6 is made entirely from plastic and is around 24mm in diameter, 200mm in height, and has a wall thickness of around 8mm. The sleeve 6 is typically injection moulded. The sleeve 6 is seated on the purlin 3 at the bottom of the cylindrical hole 4. The plastic sleeve 6 has an outer surface having threads 7 at a lower end thereof, the threads 7 extending along about half of the length of the sleeve 6, to a point beyond the circular aperture 5.

Seated around the plastic sleeve 6, on top of the circular aperture 5, is a compressible sealing washer 16. Seated on top of the sealing washer 16 is a nut 15, typically of plastic, e.g. NylonhM. The nut 15 has internal threads that are engaged with the external threads 7 on the sleeve 6. The nut 15 is a wing nut and has tightening wings so that its location on the threads 7 can be adjusted by a spanner.

The sealing washer 16 comprises a resilient seal that is axially compressed between the nut 15 and the aperture 5 in the upper roof skin IA.

The sealing washer 16 and the nut 15 together form a sealing means, with the washer 16 being arranged on the sleeve 6 between the circular aperture 5 and the nut 15 to seal the aperture 5.

The fixing device comprises a metal self-tapping screw 8 (typically stainless steel), which is located in the hollow sleeve 6. A lower portion of the screw 8 is provided with self-tapping screw threads 8T. The screw tip extends through the lower roof skin I B and into the purlin 3, so that the support assembly is fixed to the purlin 3.

An upper end of the plastic sleeve 6 supports some of the weight of a second roof structure, which comprises a profiled (corrugated) metal or plastic roof sheet 12. The second roof structure also includes a metal sub-purlin 11 (an aluminium extrusion) and mineral wool insulation filling 17.

The sub-purlin 11 is z-shaped in cross-section (see Fig 3), and has upper and lower portions (11 U, ilL) lying in planes parallel to corresponding portions of the purlin 3, and a perpendicular connecting portion 11 C. The lower portion IlL of the sub-pu nm 11 is attached to the upper end of the sleeve 6 by the screw 8, which has been inserted through an aperture in the lower portion 11 L and into the sleeve 6. The screw head 8H bears on a metal sealing washer 10, which in turn bears on a plastic sealing washer 9, which rests on top of the aperture in the lower portion 11 L of the sub-purlin 11.

The profiled roof sheet 12 is fixed to the upper portion 11 U of the sub-purlin 11 by a plurality of fixing screws 13 (one shown), which engage in apertures in the upper portion 11 U. Metal sealing washers 14 are located between the screw heads and the apertures.

A significant amount of the weight of the profiled roof sheet 12 and the sub-purlin 11 of the second roof structure is transferred via the sleeve 6 directly to the purlin 3. It is envisaged that usually, a plurality of sleeves 6 would be located at substantially equal intervals (e.g. about 1 metre intervals), to support the entire area of the profiled roof sheet 12, and the word "significant" is used to indicate that the entire roof sheet 12 would not be supported on one single sleeve 6.

By "directly" it is meant that this transfer of weight occurs independently of the first roof structure. This is possible because the sleeve 6 sits directly on the purlin 3. Hence, no or negligible weight bears on the upper roof skin IA of the first roof structure, prolonging its life, and providing a safe roof system.

By altering the height of the sleeve 6, the height of the second roof structure above the first roof structure can be varied.

A method of repairing a pre-existing roof will now be described.

The pre-existing roof comprises the metal purlins 3 and the first roof structure described above.

Firstly, the circular aperture 5 is cut out of one of the ribs lAP in the upper roof skin IA. Next, a piece of foam directly underneath the aperture 5 is cut out of the foam insulation 2, and a corresponding circular hole is cut out of the lower roof skin I B, to produce the cylindrical hole 4.

The nut 15 is screwed onto the threads 7 of the sleeve 6 from a lower end thereof, until it is substantially at the end of the threads 7, in around the middle of the sleeve 6. The compressible sealing washer 16 is inserted over the sleeve 6 from the lower end thereof so that it sits underneath the nut 15.

Next, the sleeve 6 (with nut 15 and sealing washer 16 thereon) is inserted into the circular aperture 5 and the cylindrical hole 4 so that it sits on the purlin 3. The sealing washer 16 is larger than the aperture 5, and therefore rests on top of the aperture 5.

The sub-purlin 11 is then attached to the upper end of the sleeve 6, by holding the sub-purlin 11 in position on top of the sleeve 6, by locating the metal sealing washer 10 and plastic sealing washer 9 on the self-tapping screw 8, and by inserting the self-tapping screw 8 through the aperture in the lower portion 11 L of the sub-purlin 11 and into the sleeve 6. Rotating the self-tapping screw 8 tightens the connection of the sub-purlin 11 to the sleeve 6. Rotating the self- tapping screw 8 also engages the screw threads 81 into the purlin 3 to fix the sleeve 6 to the purlin 3.

The following two steps may take place in either order.

The profiled roof sheet 12 is fixed to the upper portion 11 U of the sub-purlin 11 by fixing screws 13 and sealing washers 14. Although only one exemplary support assembly 6, 8 and one fixing screw 13 is shown, typically, many such support assemblies 6,8 and fixing screws 13 are provided, substantially equally distributed to support the entire profiled roof sheet 12. Hence, Figs I to 3 show merely part of a series of similar support structures.

The nut 15 (which was at the upper end of the threads 7) is screwed downwardly along the threads 7 such that it compresses the sealing washer 16 in the axial direction against the circular aperture 5 in the upper roof skin IA, to seal the aperture 5. The axial direction is defined by the longitudinal axis of the sleeve 6.

After the nut 15 has been screwed downwardly to compress the sealing washer 16, the mineral wool insulation filling 17 is added, as shown, in the cavity between the first roof structure and the profiled roof sheet 12. The second roof structure effectively includes the insulation filling 17, and is bounded by the upper roof skin IA of the first roof structure and the profiled roof sheet 12.

Sealing the aperture 5 has two benefits. Rain is prevented from entering the sealed aperture whilst the roof is being constructed. After construction, the sealed aperture prevents vapour from rising from the inside of the building, through the aperture 5 into the space between the upper roof skin IA and the profiled roof sheet 12, and condensing on contact with the profiled roof sheet 12.

Over time, the foam insulation 2 of the pre-existing roof (which may already be quite old at the time of repair) will compress and get thinner, and as this happens, the upper roof skin IA moves downwards.

On the release of pressure on the sealing washer 16 by the upper roof skin IA moving downwards, the sealing washer 16 (compressed when the nut 15 is tightened against it) will re-expand axially so that it still presses on the aperture 5 to maintain sealing of the aperture 5. Hence, such embodiments of the invention are able to provide long-lasting, efficient sealing of the pre-existing roof, even after the insulation 2 has further compressed.

Fig 4 shows a partial view of an alternative embodiment, which is similar to Figs I to 3, apart from the differences discussed below. Where parts are identical, the same reference numbers have been used.

The Fig 4 embodiment differs in that its support means consists of an outer sleeve 106A and an inner sleeve 106B. Both sleeves 106A, 106B are tubular, with a wall thickness of around 4mm. The outer sleeve 106A has an inner bore, in which the inner sleeve 106B is received in a close lit.

The inner sleeve I 06B has an inner bore of around 8mm in diameter.

The outer sleeve I 06A has an exterior surface that is provided with threads 107 along its entire length, and a smooth interior surface. The inner sleeve 106B is unthreaded.

The Fig 4 embodiment also differs in that its plastic sealing washer 109 has an inner bore of larger diameter than the corresponding washer 9 in Figs I to 3. The inner diameter of the plastic sealing washer 109 corresponds to the outer diameter of the inner sleeve I 06B, whereas the inner diameter of the metal sealing washer 10 corresponds to the diameter of the shank of the self-tapping screw 8.

The inner sleeve I 06B is longer than the outer sleeve I 06B by a distance equal to the thickness of the lower portion II L of the sub-purlin 11 and the thickness of the plastic sealing washer 109. The inner sleeve I 06B extends up through the aperture in the lower portion II L and abuts against the metal sealing washer 10. This is in contrast to the embodiment of Figs I to 3, in which the sleeve 6 does not extend upwardly of the aperture in the sub-purlin 11.

An advantage of the Fig 4 embodiment is that the wall thickness of each sleeve 106A, 106B is thinner, as compared to the embodiment of Figs I to 3, to provide a support means of the same overall dimension.

Referring now to Fig 5, an alternative embodiment is shown, in which the same components have identical reference numbers, and modified components are designated with the primed reference numbers. Fig 5 is very similar to Fig 2, the main difference being that the sleeve 6' extends through a trough IAT' in the upper roof skin IA', instead of through a rib lAP'. This embodiment may be more appropriate for use in repairing roofs that have an upper roof skin IA' with ribs lAP' that are narrower than the diameter of the sleeve 6' (around 24mm). The sleeve 6' and self-tapping screw 8' may be optionally, but not necessarily, shorter than the sleeve 6 and screw 8, and the threads 7' may cover a shorter length of the outer surface thereof, compared to the threads 7. One advantage of all of the embodiments of Figs I to 5 is that the

weight of the profiled roof sheet 12 and the sub-purlin II of the second roof structure is transferred via the sleeve 6 directly to the purlin 3. By "directly" it is meant that the transfer of weight occurs independently of the first roof structure. This is because the sleeve 6 sits directly on the purlin 3. Hence, no or negligible weight is brought to rest on the upper roof skin IA of the first roof structure, prolonging its life, and providing a safe roof system. This is especially beneficial if the invention is used to repair a pre-existing roof, which has been in use for a considerable period of time, and may already be quite weak.

A further advantage is that, because most of the weight of the second roof structure is being transferred to the purlin 3 independently of the first roof structure, this weight is not pressing down on the upper roof skin IA of the first roof structure. Hence, compression of the foam insulation 2 in the first roof structure (which occurs over time) is not accelerated.

Yet another advantage is that, as the second roof structure is fixed by a secure fixing (the self-tapping screw 8) directly into the purlin 3, whilst avoiding any direct, load-bearing connection to the first roof structure, the fixing of the second roof structure is always secure, and unaffected even if the first roof structure compresses over time.

A further advantage is that the aperture in the first roof structure is sealed, which prevents or reduces condensation building up within the roof system, and protects the interior of the building from rain and other bad weather, during construction/installation/repair.

Another advantage is that "cold bridging" is prevented. Cold bridging is where outside temperatures are transferred to the inside of a building, by conduction through highly conductive materials, e.g. metal.

The profiled roof sheet 12 of the second roof structure is fully insulated from both the first roof structure and the purlin 3, by the sleeve 6 and the plastic sealing washer 9. The self-tapping screw 8 is metal and therefore carries a path of good conduction from the metal purlin 3, to the top of the screw 8.

However, in Figs 2 and 5, the screw 8 is insulated from the metal sub-purlin 11 by the plastic sealing washer 9 and by the plastic sleeve 6; there is no metal-metal connection at this point.

Likewise, in Fig 4, the self-tapping screw 8 is insulated from the metal sub-purlin 11 by the plastic sealing washer 109 and by the plastic inner sleeve I 06B; again, no metal-metal connection.

Hence, there is no path of good conduction linking the second roof structure with either the first roof structure or the purlin 3, and cold bridging is therefore prevented.

The use of the invention in the field of repairing a pre-existing roof has the advantage that the life of the roof may be extended by around 50 years, whilst improving the insulation of the building, with minimal creation of waste and impact on the environment. The profiled roof sheet 12 may typically comprises aluminium roofing/cladding, which generally requires no maintenance, and is fully recyclable and has considerable scrap value.

Hence, the invention substantially assists in reducing fuel/heating costs and extending the life of a roof of a building that would normally require to be replaced.

A further advantage is that around 90% of the components used in the present invention are recyclable and easily separated for selected disposal. This is in contrast to conventional roof systems, which typically include components that are permanently secured together and cannot be separated for disposal and recycling.

Modifications and improvements may be incorporated without departing from the scope of the invention. For example, in these embodiments, the corrugations of the first roofing structure are trapezoidal, however, alternative embodiments may have different configurations, e.g. rounded.

The invention can also be applied to non-corrugated roofs.

The apparatus and method of the above invention do not necessarily relate only to repair of pre-existing roofs, and can equally be applied to construction of new roofs.

The sleeve 6 of Figs I to 3 could alternatively have threads covering the entirety of its exterior surface, or a larger proportion of its exterior surface.

Having a significant proportion of the exterior surface of the sleeve 6 being threaded is beneficial, because this allows the sleeve 6 to be used with first (pre-existing) roof structures having a wide variety of thicknesses (depths). The threads should preferably extend for a greater length than the largest possible envisaged thickness of first roof structure, so that the some threads will always be above the aperture 5, even in the thickest roofs. Typically, the threads extend to about 100mm from the base of the sleeve 6.

The outer sleeve 106A of Fig 4 could have threads on a smaller proportion of its exterior surface.

The order in which the method steps are carried out is not essential to the invention and may be altered, if practical.

The fixing device does not necessarily comprise a screw 8 that extends through a bore of a sleeve. In an alternative embodiment, the support assembly could comprise a solid body.

The mineral wool insulation filling 17 could be fibreglass, rock fibre, or could be replaced by any other suitable insulation material.

In an alternative embodiment, it is not essential to cut an aperture in the lower roof skin 1 B. Instead, the cylindrical hole 4 could solely be through the insulation material 2, and the base of the sleeve 6 could be seated on top of the lower roof skin I B, instead of directly in contact with the purlin 3.

The invention may be applied to walls in the same way as applied to roof, to over-clad an existing masonry or metal wall or to produce a new, double-skinned wall. In this case, an inner wall would take the place of the first roof structure, and an outer wall would take the place of the second roof structure. Optionally, the inner wall could be a pre-existing wall, which is being reinforced/repaired in the method of the invention. The apparatus and method used would be the same as described for roofs.

For example, a hole would be formed in the inner wall through to the cladding rail and the sleeve 6 would be attached to the cladding rail using the self-tapping screw 8, etc. All features of the invention may optionally be applied to this embodiment.

The invention is suitable for repairing/upgrading bonded panel roofs, membrane/felt roofs, and composite panel roofs (not exclusively). The first roofing structure does not necessarily have a corrugated upper skin; for example, membrane/felt roofs typically have a corrugated lower skin and a flat panel bonded to an upper side thereof, providing a flat upper roof surface. In this case, the invention would work in the same way, with the sleeve 6 being inserted through the flat panel and the corrugated lower skin; the seal and nut being located around the aperture in the flat panel.

Claims

Claims 1. A building system comprising: a plurality of structural

supports; a first building structure supported by the structural supports; a second building structure located adjacent to the first building structure; and at least one support assembly that supports some of the weight of the second building structure; wherein the support assembly extends through an aperture in the first building structure, and wherein the building system also includes a sealing means arranged on the support assembly to seal the aperture in the first building structure, the sealing means comprising a resilient seal that is axially compressible on application of pressure in an axial direction, and is adapted to expand axially if such pressure is released, to maintain sealing of the aperture.
2. A building system as claimed in claim 1, wherein the building structure is a roof structure. * ** * * S
3. A building system as claimed in claim 1, wherein the building * S*S structure is a wall structure. S. S * . . * S.

25
4. A building system as claimed in any preceding claim, wherein the : *. sealing means includes seal compression means. *SSS

S S..
5. A building system as claimed in claim 4, wherein the seal compression means comprises a nut.
6. A building system as claimed in claim 5, wherein the seal is arranged on the support assembly between the aperture in the first building structure and the nut.
7. A building system as claimed in claim 5 or claim 6, wherein the support assembly has external screw threads and the nut has internal screw threads engaged therewith.
8. A building system as claimed in any preceding claim, wherein the support assembly comprises a support means and a fixing device.
9. A building system as claimed in claim 8, wherein the support means is hollow and the fixing device is located within the support means and engaged with a structural support to fix the support assembly to the structural support.
10. A building system as claimed in claim 8 or claim 9, wherein the fixing device comprises screw threads.
11. A building system as claimed in claim 10, wherein the fixing device *:*::* comprises a self-tapping screw, a self-drilling screw or a bolt. *S.. * * *S*.
12. A building system as claimed in any of claims 8 to 11, wherein the support means comprises an outer sleeve and an inner sleeve located 25 within the outer sleeve. * .*
13. A building system as claimed in any of claims 8 to 11, wherein the *** support means comprises a single component.
14. A building system as claimed in any of claims 8 to 13, wherein the support means comprises a plastics material.
15. A building system as claimed in claim 14, wherein the support means is entirely formed from a plastics material.
16. A building system as claimed in any preceding claim, wherein there is no unbroken path of metal to metal contact between the structural supports and the second building structure.
17. A building system as claimed in any preceding claim, wherein both the first building structure and the second building structure comprise insulation material.
18. A building system as claimed in any preceding claim, wherein the support assembly is fixed to a structural support such that the support assembly transfers said weight of the second building structure directly to that structural support.
19. A method of repairing a pre-existing building comprising a first building structure supported by structural supports, comprising the steps of: S..

making an aperture in the first building structure; *..: locating a support assembly in the aperture; : 25 fixing the support assembly to the pre-existing building; : *. supporting a second building structure on the support assembly; * and S..

sealing the aperture in the first building structure by the steps of: fitting a resilient seal around the support assembly; compressing the resilient seal in the axial direction against the aperture in the first building structure; and fixing the resilient seal in its compressed configuration, such that, on any release of pressure on the resilient seal by the first building structure, the resilient seal will expand to maintain sealing of the aperture.
20. A method as claimed in claim 19, wherein the step of fixing the support assembly to the pre-existing building comprises fixing the support assembly to one of the structural supports, such that the support assembly transfers the weight of the second building structure directly to the structural support.
21. A method as claimed in claim 19 or 20, wherein the support assembly comprises a hollow support means and a fixing device, and the step of fixing the support assembly to the pre-existing building comprises inserting the fixing device through the hollow support means and engaging the fixing device with one of the structural supports.
22. A method as claimed in any of claims 19 to 21, wherein the building structure comprises a roof structure. * ** * * * * **
23. A method as claimed in any of claims 19 to 21, wherein the building S...

structure comprises a wall structure.

25
24. A support assembly for a building system comprising first and : *, second building structures located adjacent to each other; * wherein the support assembly is adapted to support some of the S..

weight of the second building structure; and wherein the support assembly has a sealing means arranged thereon, the sealing means comprising a resilient seal that is axially compressible on application of pressure in an axial direction, and is adapted to expand axially if such pressure is released; wherein, in use, the support assembly extends through an aperture in the first building structure, and the sealing means seals the aperture in the first building structure.
25. A support assembly as claimed in claim 24, wherein the sealing means also includes seal compression means for compressing the resilient seal.
26. A support assembly as claimed in claim 25, wherein the seal compression means comprises a nut.
27. A support assembly as claimed in any of claims 24 to 26, wherein the support assembly comprises: a support means having external screw threads; and a fixing device adapted to fix the support means to the building system.
28. A support assembly as claimed in claim 27 when dependent on claim 26, wherein the nut has internal screw threads adapted to engage the external screw threads on the support means. * S..

*..:
29. A support assembly as claimed in claim 27 or claim 28, wherein the 25 support means is hollow and wherein the fixing device is adapted to fit : *. within the support means. S..
30. A support assembly as claimed in claim 29, wherein the support means terminates in a lower face, and wherein the fixing device has structural support-engaging means extendible through the lower face of the support means.
31. A support assembly as claimed in claim 30, wherein the structural support-engaging means of the fixing device comprises screw threads.
32. A support assembly as claimed in claim 31, wherein the fixing device comprises a self-tapping screw, a self-drilling screw or a bolt.
33. A support assembly as claimed in any of claims 27 to 32, wherein the support means comprises an outer sleeve and an inner sleeve.
34. A support assembly as claimed in any of claims 27 to 32, wherein the support means comprises a single sleeve.
35. A support assembly as claimed in any of claims 27 to 34, wherein the support means comprises a plastics material.
36. A support assembly as claimed in claim 35, wherein the support means is entirely formed from a plastics material. * I. * * * * **
37. A building system as hereinbefore described with reference to the ** *:*. drawings.

25
38. A method as hereinbefore described with reference to the drawings. * ** * S S S...

*
39. A support assembly as hereinbefore described with reference to the S..

drawings.