Minimum Falls to new membrane decks and gutters in the Auckland Council region,

There have been a few changes lately with regards to the minimum fall requirements for gutters, decks and flat roofs in the Auckland region. We now have clarification and approval from both ARDEX and Auckland city council for the following minimum falls;

For ARDEX Butynol,  ARDEX Shelterbit (Torch-on) and ARDEX TPO

Roofs:  - 1:30 (2 Degrees)
Decks - 1:40 (1.5 Degrees)
Gutters - 1:100 (.6 Degrees)

NB: Although 1:100 is the MINIMUM requirement for gutters, we always advise as much fall as is possible under the circumstances!

If you would like some further information follow the link below to the Auckland council website:
http://www.aucklandcouncil.govt.nz/SiteCollectionDocuments/buildingpropertyconsents/forms/ac1136externalmembranesregister.pdf

Green Roofs, Living Roofs - Beautiful and Environmentally sound

I was asked last week if we install membranes for green roofs - the answer? An emphatic 'yes!'

Green roofs, (or living roofs as they are sometimes known), are both beautiful and environmentally sound.

Green roofs reduce storm water runoff, reduce heat reflection, and, provide insulation. Additionally, plantings  absorb Co2 and the flora creates habitat for fauna which further benefits the eco-system of the roof and its surrounds.

Although popular in Europe, green roofs are less common in NZ - which really is a shame. As our cities become more intensely populated it's become more important than ever to consider the overall affect that structures have on both the occupants and the surrounding environments. Why have a flat grey roof when you could have a flowering meadow - or a deck with lush grass instead of tiles?

From a technical perspective there are several membrane options available. Personally we prefer to use sheet membranes, butynol, eco-butynol, or TPO.

There are also bitumen based torch on membranes, however we refuse to use them for green roofs as the capping layer usually has herbicide impregnated into it, to prevent roots causing damage - it's a purely personal belief, but I think herbicides are a bit contradictory to the concept of green roofs - the chemicals will ultimately end up in the environment - not good!

With Butynol or TPO water runoff is 100% potable - it just makes more sense!

If you're considering a green roof or want to know more, please give us a call - we'd love to be involved 

Torch on/ Nuraply Vs. Butynol - which is the best?

I get asked a lot about which type of roof membrane is the best - Bitumen based torch on systems or a rubber system like Butynol?

The honest answer is  - neither. Both are great products when installed properly, and both suit different applications.

Torch on products are widespread, there are at least half a dozen companies importing these types of systems (all of which are not created equally!) into NZ currently, from a variety of places (USA, Italy, Holland, Belgium  Middle east). This naturally means that there are many more sales reps promoting these products to Architects and builders than Butynol, which is made in NZ by one manufacturer (Ardex, in Christchurch).
Although other suppliers buy Butynol off Ardex and re-brand it as their own, commercially speaking it is more in their interests to promote products they import and can make better margins on.

We've been running for over 10 years now and have laid pretty equal quantities of both products. Our experience tells us that the answer to the debate really lies in asking the correct questions. Eg, what is the substrate? Is the job a roof, gutter, or, deck,?  Is water being collected for drinking? Will it be walked on / tiled/ covered? What aesthetics are required? How much detailing?

At Masterseal our policy is to consider each job on its merits and provide recommendations based on experience - we always ask ourselves; 'If this was my house, what would I use?'  Because when it's all said and done we're about watertight, robust solutions that last. No cutting corners, no commercially driven 'axes to grind', just the best product for the job, and the best workmanship EVERY TIME.

Undertile Butynol

We've just added a fantastic new product to our range - Ardex WPM750 aka Undertile Butynol.

This innovative product is for use in bathrooms prior to tiling.
Undertile butynol is strong - much stronger that traditional liquid applied or 'paint on' systems, has heat welded seams and is fully compatible with most tile adhesives.
Among its many excellent attributes is its fast turnaround time - it can be tiled on only 1 hour after installation and is installed in one visit - no waiting for a second coat!

If you'd like to know more about this or any of our bathroom waterproofing systems, including Newline shower bases, please give us a call!

Bevan @ Masterseal NZ ltd

Nuraply and other single layer bitumen membranes.

We've been receiving more and more 'SOS' emails from people with leaking Nuraply and other Single layer bitumen (torch on)  roofs lately, so I thought I'd take a moment to post about them.

For a few years now it's been required by councils that all 'torch on' or bitumen based membranes be double layer systems. This was to bring NZ into line with overseas practice, and also due to a high number of failures of single layer systems.

Unfortunately for many home owners this change came too late, and they are now stuck with an ailing single ply bitumen based roof.

There are a few common issues:

- Break down of membrane due to UV (often seen as crazing, and cracking)
- Loose membrane due to adhesive failure
- Raised or wrinkled sections (often in conjunction with the above symptoms)
- Failing seams
- Failing Gel coats (eg on NURAPLY systems)

NB: If you collect rainwater for drinking off of your roof it is crucial that your gel coat is intact or that the surface is painted - Un-coated bitumen contains carcinogens and is not suitable for potable water!

Very often these issues are present together and exacerbate over time.

The good news is that these issues can be remedied - there are a number of different solutions depending on the nature and severity of any problems. If in doubt, please get in touch - we're always happy to answer your questions and suggest a solution.

Bevan@ Masterseal NZ ltd