I am researching for uni, got an enviroment project mainly to do with highways and transport.
Been writing about the Urban Heat Island effect due to the vast amounts of landscape overtaken with tac mac especially in the UK, from my understanding (which is minimal on this subject at the moment) we could reduce the Urban Heat Island effect by colouring tarmac producing a lighter colour. Also Green roofs could help but how do structures react to having green roofs ( i know that roofs are designed to carry vast snow loads which may never occur in the buildings life) but can green roofs be added to existing structures? or is it just viable to be incorperated into new builds? If anyone has a knowledge of environmental engineering or a structural engineering knowledge, I would be greatful any input or suggestions
Thanks
Tony
Link removed/

You could start here

There is a lot that could be done, that isn't for many reasons.

Green roofs are useful, but really are just another patch stuck on the underlying problems - probably more useful for drainage rather than heat island problems.

Be careful of so called "reflective" tarmacs - you can end up re directing heat to where you really don't want it.

One thing you may want to look at is how to capture the heat that falls on tarmac and use it for winter use - as a kick off take a look at this - look at interseasonal heat storage and let your imagination go from there.

Regards

OMS

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Failure is always an option

Having learn somthing...

One of the new school building had a 'green roof' near to where I am. Lots of claims were made when it was installed, but a few years down the line and it has gone from needing a good mowing to the current brown field look.

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Norman

I guess Green Roofs can also help in reducing or maintaining heat thats why they are used in tree houses, and plant nurseries...

Roofing Services

One of the new institution developing had a 'green roof' near to where I am. Plenty of statements were created when it was set up, but a few decades down the range and it has gone from requiring an excellent cutting to the present Turkish area look.

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Allied Roofing Services
info@alliedroofingservices.com
Crestwood, IL, 60445 USA
(708) 415-4474

Hi Roger,

Green Roofs or Sedum Roofs because of the Sedum Plant used are ideal with improving the surface water run off from roofs and are used in helping to obtain the 20% renewables from new builds or large refurbishment construction projects. (government directive) They can also assist with heat containment as well.
As long as they are maintained on an annual basis, their growth rates are very slow; cleared of debris, dead leaves etc they look fine.
What ever you do don't ever incorporate a green roof if there is a problem with Japonese Knotweed in the close proximity of the site or location.
I was recently managing a school construction project where a green roof was specified. Later we discovered there was substantial knotweed growth on a nearby river bank.
So the green roof was omitted and we then changed the spec of the roof i.e. enlarged the ZED sections for the flat roof construction to enable an array of photo voltaics to be fitted to achieve the 20% renewables.
I hope this helps.
Keep up the banter!

One of the problems with this type of roof is the extra structural requirements, and a nightmare with penetrations, according to the structural engineers at the place where I work, in Canada.

Although, arguably, the extra structure translates to extra mass which is all good in damping diurnal swings of the building indoor temperature.

I would have thought penetrations would be no more "difficult" than normal - at lesst they haven't been on any projects I've worked on that had green roofs.

Regards

OMS

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Failure is always an option

Hi Mr OMS , I don't enough idea about it until posted here.

Thanks

Green rooftops are often determined as one of two major types: comprehensive, or superficial green rooftops, and comprehensive, or deep green rooftops. These kinds have different features and performances and are suitable for different design objectives, architectural requirements and ceiling conditions.

Why pay for slates or tiles when you can dig it out of your garden. You need to get the liner right and protect it while you lay the turf. Also, barge boards tend not to last so do without if you can. Wild flowers are easy but if its not tended, it will end up looking like any other garden.

Quite common where I live and I'm currently planning to retrofit a felt foof.

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Chris Matheson MInstMC

learning a lot from this site....

Nowadays, therea re really a lot of people who wants to live the dream of green living. In my opinion, I prefer it since it helps a lot in our environment and also helps to conserve energy and many other advantages like, green roofs last longer than conventional roofs

Green roofs are useful, but really are just another stuck patch on the underlying problems - probably more useful for drainage rather than heat island problems.

Edited: 28 March 2013 at 03:16 AM by laptopfullcare