How to take a rusty roof and get it looking like new
July 4 2014
RUSTY BROWNBUILT ROOFING IRON THAT WAS ABLE TO BE SALVAGED.
DO YOU HAVE A RUSTY GALVANIZED IRON ROOF THAT NEEDS TO BE COATED WITH A LONG-LASTING, ANTI-CORROSION, WATERPROOFING MEMBRANE PAINT SYSTEM.
Modern Maintenance Products have been providing cutting edge products for rusty roofs since 1993 saving the owners many thousands of dollars. Our product range has been tried and tested in New Zealand’s rugged conditions and has proven to be a very durable and hard wearing product.
See below for some hot tips to know before you get started.
Before you can coat your rusty roof , one needs to inspect the roof and check for the following problems.
(1) Does the roofing iron along the drip line into the gutters, have any small pin-holing along the ends of the sheets?
If so, then using a mirror or by feeling under the sheets, check for scale rust.
If it is badly corroded, the term, rusting from the underside out applies and no matter how much anti –corrosion coating you apply to the top side, it will not stop the corrosion from the underside.
If this is the case, and the rest of the iron appears in relatively good condition, albeit that the zinc cathodic protection is diminishing and showing signs of surface rust, then the bottom of the sheets can be cut and new slip sheets can be inserted along the gutter line.
Before these are installed and especially if in a coastal environment,
It would be advisable to apply the Noxyde anti-corrosion coating to the underside of the sheets before installing.
(2) Corrosion on the underside of steel roofs is caused by chloride or salt laden air being blown up into the roof cavity and if it does not get regular rain washing, will cause the zinc or previously painted sheets to rust.
So if in a coastal environment or if the roof is in a factory situation where atmospheric chemical corrosion from within may be a problem, then it is also necessary to check under the building paper and along the roof capping’s for any underside corrosion.
If it is excessive then you might find that all the overlaps have corrosion between the sheets and it might be a case of replacing the entire roof.
If on the other hand, the underside is corrosion free but the topside has surface rust forming, then your roof can be prepared and coated with Noxyde, the only anti- corrosion waterproofing membrane on the
market in New Zealand.
(3) If the roof has been checked and found to be sound, then the final process would be to check the fasteners to make sure they are all still sound.
The Noxyde anti-corrosion water-proofing membrane is going to completely seal up around these forming a flexible rubber like finish.
That will not crack or become brittle for its lifetime of 15-20 years plus.
(4) The most cost effective method of applying the Noxyde coating is with an approved airless spray unit.
The coating will be applied in two coats to achieve a minimum dry film thickness of 350 microns forming a thick polymer rubber membrane that will allow for 200% elongation and will handle any thermal expansion when the roof heats up in the sun.
(5) Noxyde is a single component, odourless waterbased product that can be washed up in water, has excellent shelf life, and a 30 year plus recorded performance history for complete corrosion protection without losing its flexibility.
If you have any questions about this process, then please contact us.
We have some very skilled Applicators who can advise you and apply the product, if it is established that your roof is salvageable.