Flat Roof Pro's Corner

Tag: roof coatings

Metal Roof Coatings

by on Dec.08, 2010, under Flat Roofs

A metal roof can be a challenging roof surface to seal from the elements.  One of the major factors is the constant expanding and contracting of the roof surface itself.  A metal roof can expand and contract as much as 2 inches every 100 feet which can be devastating to fasteners and seams, which 90% of all roof leaks occur at these points.

If you are experiencing problems with a metal roof then the two options are to either replace the roof which can be extremely expensive and time consuming or restore it with a elastomeric roof coating, which can be very cost effective as compared to replacing the roof.

A high quality elastomeric roof can add many years of life to your existing roof, they come in many different forms but the high quality ones are generally more expensive but should be the only choice.  Lower cost coatings dont stretch as well and seldom have the proper UV protection built into them.

Another key feature in Elastomeric roof coatings are the energy savings you will benefit from them.  Immediatly after coating the metal roof surface its temperature can drop as much as 40 degrees or more in a very short period of time.  This reduction in heat transfer from your roof will make your building much cooler and will save your money in your energy bills.

The roof coating however does not simply just work alone, there are steps necessary to ensure that your roof is properly sealed from the elements.  The first thing that must be done is to ensure a clean roof surface, this should be done with a high power pressure washer to remove hard to get roof scum.  Next you need to go around the roof and spray all rusty areas with an inhibitor to stop further corrosion of the metal.  You should then go around and reinforce any where there is a roof penetration with elastomeric roof cement, by penetrations I mean pipes, air ducts, fan units and any other areas where there is something entering through the roof surface.  You them also need to go reinforce or replace rexisting roof flashings that may be running around the roof.  After the roof has dryed the next step is to seal fasteners individually with a rivet guard type material and all missing fasteners should be replaced as well.  After this step you must individually seal every seam with a seam guard, this is usually a roll out tape, a really thick elastomeric cement or a combination of both of pending on the product you are using.

Now finally you can coat your roof with the final roof coating to finish the job.  You will need a roof coatings sprayer which you can pick up from a paint supplier just be sure that you change the sprayer head with the proper size for your roof coating.  You may need a primer coat depending on which product you are using and you should put down two coats of finish roof coating material as well.  Be sure that the roof surface is dry and that now rain is forcasted for the day you decide to finish the roof.  Elastomeric coating will not stick to a wet roof surface so be sure that it is good and dry.  Temperature is also an important factor, it should be no less then 55 degrees to put down the roof coatings to ensure that it cures properly.

That is pretty much how you would go about sealing your metal roof.  You should hire a qualified roof coatings contractor to do the work but if you need to save money you can complete the project yourself.

Leave a Comment :, , , , more...

Asphalt Surface Roof Repair

by on Dec.07, 2010, under Flat Roofs

If you own an old commercial building with a flat roof odds are you have an old asphalt roof of some type.  These roof surfaces are made up of layers of felt paper  and tar stacked up on each other which over the years will or have given you alot of headaches.  They are usually just felt paper or the are covered with a layer of gravel, the gravel in theory was to help keep the roof cooler which it does a little but it makes repair much more difficult.

One of the biggest problem with asphalt surfaces is that they dry up and shrink which eventually leads to cracking and this will cause your roof to leak.  In order to keep your asphalt roof in good condition it must be maintained.  To accomplish this you should have your roof re-coated with an asphalt based coating at least once every five years or so, if you don’t it can lead to expensive and time consuming repairs.  Over the years your roofs crucial oils are weathered out of the roof surface and it must be restored to maintain integrity, if you have areas with standing water then the process speeds up and your roof will fail in that area most likely first.

If you are on of the unfortunates owners of a gravel roof then you can have even bigger problems.   Gravel was put on in a time when it was thought it would be beneficial to help reduce the roofs temperature with cheap gravel, it worked a little but not very much.  Gravel roofs undergo the same problems as a regular felt roof but the leaks and standing water areas are much harder to spot.  Another huge problem is maintaining the roof, in order to do a maintenance coating all the gravel must be removed.  Sounds easier than what it is, you should contract out a gravel suction company to complete this task, but if you are feeling like you need a good workout a few flat shovels and a broom will do the job as well.

Another problem that asphalt roofs face are blistering problems.  Blistering occurs when moisture works it way in between the roof layers and expands forming a huge gas pocket, eventually these pockets will expand to a breaking point and crack open, thus leaving you with a hole in your roof.  If you have blistering problems you must cut them open with a cross cut so you can fold back the edges and fill them in with roof cement, then fold the cut edges back over the cement thus resealing your roof.

There are a few types of roof coatings that can be used to remedy and repair your roof problems.  The most commonly used are asphalt based but if you want a better longer lasting coating you should consider using a elastomeric roof coating, they are much more durable, more energy efficient and longer lasting than asphalt coatings.

Asphalt coatings are generally black or silver in color and have a life span of about five years if appleid correctly.  They are generally the cheapest of the roof coatings but if you decide to go with this system be sure to purchase ones that are fiberglass embedded, they are much better at stopping and repairing leaks.

Elastomeric coatings are generally white in color and have a life span of 10 to twenty years, there are a few with a 20 year warranty as well, but they are very expensive.  Elastomeric roof coatings work very well especially when combined with fiberglass mesh system as its base.

Leave a Comment :, , , , , more...

Looking for something?

Use the form below to search the site:

Still not finding what you're looking for? Drop a comment on a post or contact us so we can take care of it!

Archives

All entries, chronologically...