Securing

Loose stone

on Rooftops

A resource for Strata Committees

and Building Professionals to

better understand products and

methods to prevent falling stone.

Low

Cost

Vehic

le tr

affic

Inst

allat

ionCo

oling

/ Te

mpMa

inten

ance

10yr+

War

rant

ySa

fety

Why is stone used for Rooftops?

Cost*

Ÿ Cost - Gravel and plastic are relatively cheap to manufacture. Though patented designs and UV treatment make premium brands expensive.

Ÿ Strength - When filled and compressed properly, high quality grids are able to withstand very heavy vehicles such as mining trucks and other plant equipment

Ÿ Installation - Does not require special skill as grids clip together by hand and stone can be backfilled manually or using earthmoving equipment.

AdvantagesDisadvantages

From an environmental perspective, Local Government is leading State and Federal Governments in Water Sensitive Urban Design (WSUD).

As population density increases so too does building size, and the effects of hard surface foot print on the local environment. Over-development can result in environmental and infrastructure problems (such as overloading fixed capacities of existing stormwater systems).

Consequently, many Councils require new development to maintain a balance of the ‘hard to soft landscaping ratio’. The extent to which councils incorporate WSUD into residential development applications depends mainly on population densities and environmental credentials of the municipality.

Whilst Federal and State government don’t currently offer any rebate for homeowners installing water sensitive paving, many local government councils do provide a financial incentive.

Permeable paving is different from Porous paving. One of the common headaches for homeowners is why councils reject use of some paving products whilst approving others.

Permeable paving is where rainfall can reach the ground water table by trickling down gaps around a hard surface, such as sand between pavers.

Porous paving is where water travels through pores or voids in the hard surface itself. The latter typically has a higher rate of water penetration and larger surface area (capable of capturing more water). Consequently porous options are more favourable with councils in the development application process.

The information in this guide has been compiled by StoneSet, a supplier and installer of Resin Bound Porous Paving. It will be independently approved in March 2019 as suitable for industry directed professional development training for Architects, Engineers and Landscape designers.

Combination

Aest

hetic

ape

al

Non-

Intrus

ive

Safe

for A

nimals

Essentially forms of pest control, there are various means of preventing the undesirable side effects of birds inhabiting urban building spaces. Broadly categorising, these range from ‘physically deturrants’ such as spikes, exclusion barriers like netting, electrical deturrants such as hot wires and ultrasonic emitters and finally chemical baiting programs, particularly where previous methods have failed and peoples safety remains at risk.

What can be done to stop Birds dropping loose stone?

www.tiroearthworks.com.au 0477 646 559 Dianella WA 6059

Solution - Binding Loose Stone

Bind Gravel from below! Don’t Net from above.

What is the ‘best choice’ to stop falling stone?Each pest control product has advantages and cost implications. Barrier controls like bird spikes and netting are most prevalent in cities, typically as it is the first, simplest barrier control people think of, especially during an urgent situation of birds dropping large stone. However compared to simply binding loose stone, planning and rigging bird netting takes more time and is more complicated, meaning a longer quote-supply-installed lead time.

Other methods such as electrical ultrasonic deterrents are expensive and the electrical equipment is exposed to wind and rain and prone to longer term failure. Chemical baiting programs are highly effective and more reliable, however these are more labour intense and therefore more costly. Our cost estimate is provided on page 4.

Post Elevated Netting

Ballast Style Netting

The whole reason natural, loose stone is architecturally specified for rooftops is to protect waterproofing membrane (a man-made, petrochemical product) from the damaging effects of the Sun’s UV rays.

Whilst netting is effective and reliable in the short term, it is still a plastic, polyethylene based material. Regardless of netting being UV stabilised and high density woven, it is constantly under tension and exposed to UV all day, every day.

Alternatively, the PourOn biding resin is never exposed to the sun! After being poured over dry, existing rooftop stone the polyurethane trickles down, coating the stone and curing dry in 12 hours. This binds the stone into a solid, cross -linked matrix, interlocking at multiple touch points between the stone. The result? A very strong binding matrix that is completely water-inert and never exposed to damaging UV rays.

PourOn rooftop bound stone experiences practically no erosion (hidden from UV, Water inert polyurethane no friction or weight from foot traffic, as a rooftop). Consequently, these rooftops effectively bind stone against pests like birds for exceptionally long periods of time.

What Warranties are available to me?Typically you will find warranties offered by contractors providing pest control will not cover damage from falling loose stone.You should double check with your insurance company if such damage is covered by the buildings’ existing Public Liability insurance. Careful consideration should be given to ‘product warranties’ offered and the years-in-trading of each company. For example, many netting suppliers do not warrant damage from storms (which, realistically is when brittle, 5 year old polyethylene netting is most likely to rip). PourOn offers a 15 year warranty (when installed by PourOn) and extends to re-sealing any areas identified as having loose stone. Please read the last page of this brochure for conditions of this warranty.

Low

Cost

Vehic

le tr

affic

Inst

allat

ionCo

oling

/ Te

mpMa

inten

ance

10yr+

War

rant

ySa

fety

Cost*

Ÿ Cost - Gravel and plastic are relatively cheap to manufacture. Though patented designs and UV treatment make premium brands expensive.

Ÿ Strength - When filled and compressed properly, high quality grids are able to withstand very heavy vehicles such as mining trucks and other plant equipment

Ÿ Installation - Does not require special skill as grids clip together by hand and stone can be backfilled manually or using earthmoving equipment.

AdvantagesDisadvantages

From an environmental perspective, Local Government is leading State and Federal Governments in Water Sensitive Urban Design (WSUD).

As population density increases so too does building size, and the effects of hard surface foot print on the local environment. Over-development can result in environmental and infrastructure problems (such as overloading fixed capacities of existing stormwater systems).

Consequently, many Councils require new development to maintain a balance of the ‘hard to soft landscaping ratio’. The extent to which councils incorporate WSUD into residential development applications depends mainly on population densities and environmental credentials of the municipality.

Whilst Federal and State government don’t currently offer any rebate for homeowners installing water sensitive paving, many local government councils do provide a financial incentive.

Permeable paving is different from Porous paving. One of the common headaches for homeowners is why councils reject use of some paving products whilst approving others.

Permeable paving is where rainfall can reach the ground water table by trickling down gaps around a hard surface, such as sand between pavers.

Porous paving is where water travels through pores or voids in the hard surface itself. The latter typically has a higher rate of water penetration and larger surface area (capable of capturing more water). Consequently porous options are more favourable with councils in the development application process.

The information in this guide has been compiled by StoneSet, a supplier and installer of Resin Bound Porous Paving. It will be independently approved in March 2019 as suitable for industry directed professional development training for Architects, Engineers and Landscape designers.

Combination

Aest

hetic

ape

al

Non-

Intrus

ive

Safe

for A

nimals

Essentially forms of pest control, there are various means of preventing the undesirable side effects of birds inhabiting urban building spaces. Broadly categorising, these range from ‘physically deturrants’ such as spikes, exclusion barriers like netting, electrical deturrants such as hot wires and ultrasonic emitters and finally chemical baiting programs, particularly where previous methods have failed and peoples safety remains at risk.

What can be done to stop Birds dropping loose stone?

Problem - Loose Rooftop Stone

Who is responsible for damage by falling stone?The buidlling owner is responsbilbe for peoples safety in and around their property Unfortunately this makes the Owners Corporation of residential Strata Title complex’s liable for damage caused by birds dropping loose stone from the complex rooftop.

Why is large loose stone placed on Rooftops?Despite the danger of birds dropping loose stone from roof tops, Architects and Builders continue to use loose stone for rooftops. There are very good reasons for this.

All flat-top building roofs must be built with sound drainage and waterproofing. The problem is Waterproofing is a synthetic polymer and highly susceptible to UV damage (particularly given flat roofs are exposed to direct sunlight for up to 12hours a day). To protect this waterproofing, a stone or paving product must be used to shade the waterproofing and take the full brunt of the Sun’s UV.

A cement slab can not be poured, because the waterproofing and drains must to be accessible for any future repair works. Segmental style pavers like clay and terracotta pavers could be used, but considering the fabrication and installation costs of pavers is significant. Particularly when the area is not even foot-traffikable, paving the rooftop is cost-overkill, even when compared to a cheap concrete.

Use of a common, ubiquitous stone makes sense. It is cheap to source, it incurs little to no processing after extraction from the quarry, and practically zero installation costs as it is hoisted and spread out into place. Larger, 20mm+ size stone is the cheapest as it is not suitable for use on paths or driveway it and therefore sees much less demand in the building industry.

Therefore, raw untreated larger stone is the most suitable choice to protect waterproofing from UV damage. Except of course, when birds start picking up and subsequently droping this loose stone from 4+ stories up!

Why do Birds pick up stone?Reasons vary across different bird species. Rather than having teeth to chew with, birds possess a gizzard (similar to a stomach). These birds swallow the stone to help crush up food in the gizzard. Other birds can mistake the stone for food, while some birds are simply curious, playful and pesky with stone!

Why aren’t Rooftops paved or concreted?

AdvantagesDisadvantages

What can be done to stop Birds dropping loose stone?

15 Year warranty applies to PourOn installed by StoneSet (or StoneSet ‘Approved Installer’). A full 15 year warranty applies for non-traffked rooftops

with a maximum 20mm size stone. Warranty covers re-sealig areas identified as having loose stone and does not cover damage to property or injury

caused by falling loose stone.

of Bird Pest Control products

Chemical Baiting

Ballast Netting

Elevated Pole Netting

Hot tracks/wires

Ultrasonics + Strobes

15 Ye

ar w

arra

nty*

ZER

O UV d

amag

e Lo

oks

Good

High C

ost

(m²/

yr)

Mid C

ost

(m²/

yr)

DIY C

ost

Optio

n

PourOn Gravel Binding

Solve

d in 2

4hrs

Non I

ntru

sive

ins

talla

tion

Safe

- all

Anim

als

15 Year warranty applies to PourOn installed by StoneSet (or StoneSet ‘Approved Installer’). A full 15 year warranty applies for non-traffked rooftops

with a maximum 20mm size stone. Warranty covers re-sealig areas identified as having loose stone and does not cover damage to property or injury

caused by falling loose stone.

Advantages

From as low as $30/m² (supply)

Low

Cost

Vehic

le tr

affic

Inst

allat

ionCo

oling

/ Te

mpMa

inten

ance

10yr+

War

rant

ySa

fety

Cost*

Ÿ Cost - Gravel and plastic are relatively cheap to manufacture. Though patented designs and UV treatment make premium brands expensive.

Ÿ Strength - When filled and compressed properly, high quality grids are able to withstand very heavy vehicles such as mining trucks and other plant equipment

Ÿ Installation - Does not require special skill as grids clip together by hand and stone can be backfilled manually or using earthmoving equipment.

AdvantagesDisadvantages

Combination

Aest

hetic

ape

al

Safe

for A

nimals

What can be done to stop Birds dropping loose stone?