Roofing Material Analysis
I saw my selected roofing material posted in a thread recently, which prompts me to share the selection and the associated process. Our design will not have a great deal of roof coverage, however, our most high ranking criteria is to ensure long term durability, low maintenance and lastly noise reducing and insulative values.
Our criteria for selection were cost, appearance, ease of installation and maintainability. Cost was one of the more complex to assess as we need to bear in mind how the selection impacts substructure design and cost, as well as long term maintainence costs in order to understand the complete "cost" for each material.
After much debate, the supplier we selected is Onduline. I think the best way to summarize our process is in a very basic pro's and con's for each of the three materials we compared.
NOTE: This is a delta comparison only, as individual location, installation fees, supplier relations and negotiation strength all play in to the actual costs, I did not list the "bottom peso" cost. I find that you can get quotes etc., here in the Philippines, but until the job is done, you cannot accurately state costs since we have that ever present concern over there being a "misunderstanding sir". As part of this blog, it is my intent to share the various costs of the selected materials in the final summary. As with any of my entries, I STRONGLY encourage each to research extensively each aspect of your project and make the decision that is right for you. This is not a sales pitch for our selected product as it may not be suitable for every application.
Plain corrugated metal roof panels
PRO's: Low cost, readily available, ease of installation, low cost of installation
CON's: High maintenance (need to paint before installation and in the future, vulcaseal sealer around screws), loud during rain (minor concern), no insulative value
Tile roof material
PRO's: Appearance more high end, maintenance low, insulative value higher (due to subsurface required), quieter in rain.
CON's: High cost, high cost of installation, additional materials required to support tile material, insulative value higher than metal, increases to structural component strength to support added weight.
Onduline fiberglass panels
PRO's: Cost slightly above metal panels, Installation cost same as metal panels, slight insulative advantage over metal, slight noise reduction over metal, low long term maintenance, apparent ease of installation
CON's: New material for workers to handle, learning curve should not be long, More expensive fasteners (screws and caps)
So the pro/con list makes the decision pretty clear, for us, as even when I assigned costs to the cost related criteria, the Onduline panels came out only marginally higher than the metal panel option. I like the screw/screwcap installation method and would likely add some vulcaseal to the screw caps as an added measure of leak resistance over thermal expansion. Also, as I looked further into the various options, I was encouraged by the lack of propensity for the fiberglass material to acrue mold. Of course, the metal would be resistant as well, but require re-painting. The tiles, possibly not so resistant without regular maintenance.
We were not able to find a reliable source for developing cost comparison data for regular asphalt shingles. Our structural design will support this material as a selection and we intend on seeking a source and looking into this material to round out our comparison, when the project is underway.
An additional consideration for me was that I did not find the Onduline material until having made the decision to go with metal panels, so my roof support structure design worked with that material, and substituting the Onduline was a simple task without changes to much of the completed design.