GB2313385A - Gutter installation having weatherproofing lining - Google Patents

Abstract

Method and assembly of parts for a roof gutter installation comprises mounting a sheet metal load bearing shell of channel section carrier formation 24 in a roof valley, which can be used for access during erection of the roof, thermal insulation boards 30, 32 and a weatherproofing lining 40 which is installed in the carrier formation 24 after all other work is complete to prevent damage to the lining 40. The lining comprises an impervious flexible membrane backed by rigid or semi-rigid sheets forming a hinged construction which can be folded longitudinally to facilitate installation. The lining 40 is not attached to the carrier formation 24 so that it is substantially free from stresses caused by expansion etc of the carrier formation 24, preventing damage to the lining 40 and maintaining its weatherproof properties.

Description

GUTTER INSTALLATION This invention relates to gutter installations for buildings and similar structures, particularly but not exclusively for buildings such as commercial premises having substantial areas of pitched roofing, commonly metal clad, with consequent need for disposal of large volumes of rainwater particularly in valleys between runs of pitched roof.

It is known to form gutter installations by providing a laminated construction consisting of a profile sheet metal channel, usually with thermal insulation, and a weatherproofing lining, typically a flexible membrane bonded to the weather face of the gutter shell and sealed by adhesive, welding or the like at the joints or seams.

As the lined guttering is usually installed at a fairly early stage of the roofing process during construction, if only because roofing panels have necessarily to overlie it at the edges, it is often damaged causing leaks even before the building or other structure is completed, or has been so stressed during construction that failure is likely at an early stage after commissioning. This is because the run of gutter is inevitably, if not necessarily, used as an access platform or walkway during the construction work so that the weather side is subjected to quite heavy traffic.

The gutter is also often used for storage of substantial quantities of tools and material. Even if walkboards are provided or used (and this is by no means common) the loading on these will stress and abrade the gutter lining.

Furthermore the metal shell is subjected to movement, particularly thermal expansion and contraction and expansion joints have to be provided in long runs to accommodate this. These stresses are communicated to the bonded lining again leading to eventual failure, particularly at their weakest points, usually the joints.

It will be appreciated that any leakage of guttering to the building interior can cause very serious damage to stock or processes, also that even minor leaks and seepages can be troublesome and expensive to trace and remedy.

The object of the invention is to provide gutter installations of substantially improved reliability, having long service life and requiring minimal repair and maintenance, and which are economical to manufacture and instal.

According to the invention there is provided a method of gutter installation on a building or other structure including the steps of: providing one or more substantially rigid channel section carrier formations and mounting this or these as part of the structure to provide an outer load bearing shell of the gutter which can serve as an access platform or walkway during other work on the structure before said shell is rendered weathertight; and subsequently adding a weathertight lining resting in nested relationship within the shell and jointed and sealed to form an impervious skin, said lining not being added until a stage of the construction when it will not be subjected to any substantial access traffic or loading, and leaving the lining substantially detached from the carrier so that it is substantially free from stressing caused by expansion, contraction or other displacement of the carrier.

Preferably said lining will include thermal insulation, for example panels of pre-cut insulation board, between the carrier and an outermost weatherproof membrane of the lining.

Conveniently the lining consists of or comprises preformed weatherproofing consisting of an impervious flexible membrane with rigid or semi-rigid backing sheets forming a hinged construction which can be folded for positioning within the shell and be opened out into its installed relationship.

An example of the invention is now more particularly described with reference to the accompanying drawings wherein: Figure 1 is a diagrammatic cross-section of an installed carrier formation of a gutter installation, Figure 2 shows said carrier formation with thermal insulation added, and Fig-ure 3 shows the completed gutter installation with indication of the stages of insertion of folded preformed weatherproofing therein.

A commercial building such as a warehouse is constructed largely of metal cladding on a steel framework and has a pitched roof two areas 10, 12 of which slope towards each other to form a valley 14. The roof is of generally conventional construction supported on horizontal purlins 16 and rafters (not shown). The primary roofing surface is in this example corrugated coated steel 18 below which is a layer of insulation 20 and an interior lining panel 22.

In constructing the roof a channel section galvanized steel carrier formation 24 is mounted with side flanges overlapping and secured to the spaced lowermost purlins 16 so bridging the gap between the roof sections and forming the lowermost part of valley 14.

Formation 24 is typically of 1.2mm or thicker gauge and is bolted together in sections through holes and slots permitting movement to accommodate thermal expansion and contraction. No sealant is applied at the joints, in other words no attempt is made to make the assembled carrier formation 24 wholly weathertight at this stage.

Assembly of the roof and other construction work continues with the erected carrier formation 24 left in this state. It can be used as an access platform or walkway and for handling and storage of materials and tools whilst the construction, notably of the roof, is completed.

When the construction has reached the stage at which little or no further traffic along valley 14 is necessary the construction of the gutter installation, in particular its weatherproofing, is completed as follows.

The next stage, Figure 2, is the installation of thermal insulation, formation 24 is lined with pre-cut panels of insulation board along its length, two side panels 30 sloping upwards to fit snugly under drip flashing 32 below the eaves of the two roof sections 10, 12 and a floor panel 32.

Next the lining of the gutter installation is completed by the insertion of preformed weatherproofing 40 shown in Figure 3.

Weatherproofing 40 is manufactured as a laminate of a flexible weather resistant membrane, e.g. of E.P.D.M.

or other known durable waterproof membrane material backed by in this example four semi-rigid longitudinal backing sheets to which the membrane is bonded forming hinges so that weatherproofing 40 can be folded longitudinally as shown by broken lines in Figure 3.

This folding enables weatherproofing 40 to be manoeuvred between the roof eaves into valley 14 firstly as indicated at 40a and then progressively opened out as indicated at 40b until it overlies the exposed faces of the insulation panels 30, 32 covering the bottom and extending up the sides of the gutter profile. Joints between successive lengths of weatherproofing 40 are sealed using conventional techniques appropriate to the weatherproofing membrane material such as adhesives or other bonding compounds or plastics welding.

Preferably a breather membrane is applied over the surface of carrier formation 24, not shown in the drawings, before the insulation panels 30 and 32 are inserted.

As the weatherproofing of the gutter installation is not attempted until the construction work is substantially completed it has not been subjected to wear and damage which would otherwise be almost inevitable.

Furthermore it will be noted that the weatherproof gutter lining rests in nested relationship with the underlying and supporting carrier formation 24 but is not bonded or otherwise attached thereto. Thus differential movement can take place, particularly due to thermal expansion and contraction, of carrier 24 and of the lining independently of each other so that the lining is subjected to minimum stress and strain and the likelihood of seams or joints opening or tearing of the membrane which would cause leakage is very substantially reduced if not entirely avoided.

It is desirable to provide a fall along a gutter to aid flow towards the outfall or outfalls and to prevent or reduce accumulations of standing water. With many known gutter systems such provision is not readily made or is not carried out due to added complexity and cost of construction, e.g. the need to fabricate special metal work and/or provide special supports and packing to achieve the desired longitudinal slope. In an adaptation of the invention a fall is provided by cutting and shaping the insulation so that the lining is given the desired slope within and relative to the (generally level) carrier formation.

While a valley gutter installation has been described it will be understood that the invention may also be applied to other forms and location of rainwater disposal guttering of buildings and similar constructions, e.g. guttering immediately inboard of and bounded by an upstanding parapet or wall.

Claims (13)

1. A method of gutter installation on a building or other structure including the steps of: providing one or more substantially rigid channel section carrier formations and mounting this or these as part of the structure to provide an outer load bearing shell of the gutter which can serve as an access platform or walkway during other work on the structure before said shell is rendered weathertight; and subsequently adding a weathertight lining resting in nested relationship within the shell and jointed and sealed to form an impervious skin, said lining not being added until a stage of the construction when it will not be subjected to any substantial access traffic or loading, and leaving the lining substantially detached from the carrier so that it is substantially free from stressing caused by expansion, contraction or other displacement of the carrier.

2. A method as in claim 1 including providing the lining with preformed weatherproofing comprising an impervious flexible membrane and rigid or semi-rigid backing sheets forming a hinged construction which can be folded for positioning in the shell and opened out into installed relationship thereto.

3. A method as in claim 2 wherein the membrane and backing sheets provide at least three spaced parallel longitudinal hinges along the lining to facilitate its insertion in folded condition between the eaves of two areas of pitched roof sloping towards each other to form a valley with the shell forming the downmost part of the valley, and subsequent opening out laterally within the shell to fit beneath the eaves.

4. A method as in claim 1, 2 or 3 further including the step of installing thermal insulation between the shell and weatherproofing of the lining.

5. A method as in claim 4 wherein said insulation comprises panels of presut insulation board operatively positioned between the carrier formation or formations and an outermost weatherproof membrane of the lining, said insulation being installed in the shell when the lining is added thereto.

6. A method as in claim 5 including installation of a breather membrane to the surface of the shell before installation of said insulation.

7. A method as in claim 4, 5 or 6 including the step of forming the insulation so that the lining slopes longitudinally of the assembled gutter relative to the shell to provide a fall for effective drainage.

8. A method of gutter installation substantially as herein before described with reference to the accompanying drawings.

9. A gutter assembly including a rigid channel section carrier formation operatively forming an outer load-bearing shell, and a weathertight lining for insertion in nested relationship within the shell subsequent to mounting of the carrier formation, said lining comprising an impervious flexible membrane and rigid or serni-rigid backing sheets forming a hinged construction which can be folded longitudinally to facilitate said insertion.

10. An assembly as in claim 9 wherein the lining is hinged at at lest tliiee spaced parallel locations longitudinally thereof.

l l. An assembly as in claim 8 or 9 further including thermal insulation for operative insertion between the shell and the lining.

12. A gutter assembly substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

13. A building or other structure including a gutter installed by the method of any one of claims 1 to 8 and/or a gutter assembly as in any one of claims 9 to 12.