Getting Reflective and Vent


Anyone in the Caribbean who has walked on a steel roof will attest to the incredible heat created by the sun.
What's more painful is the radiated heat below, in the very place protecting us from the sun's rays.

Our forefathers knew what to do. The age old art of tropical ventilation. High ceilings, Jalousie windows, simple louvers and louvered shutters, gable roof vents and hip on gable roofs creating wrap around porches were just some of the practical, sensible ways in which people kept cool on blistering hot days.


As the demand for block wall homes became the answer to 'moving up' from Granny's chattel house and the costs of cement outstripped the price of lumber, be it local or imported, so the old skills of wood and the common sense of construction began to fade away. So much so, that today, although some draftsmen and builders are moving towards environmentally practical designs, the majority are still producing concrete boxes, not unlike hothouses with ill chosen windows and negligible ventilation. The abundant use of T111 beaded plywood on rafters, with a covering of corrugated roof sheeting has given rise to a resurgence of the high ceilings of old, but with the same caveat; do you have a designer who understands enough about ventilation to release the radiated heat from the roof vault, while keeping nocturnal predators out?

Each house design, in its unique way, has its own set of opportunities to create a comfortable tropical environment, without massive electrical bills generated by a huge air conditioner, or enormous exposure to the risk of mosquitos by day or by night.


Beyond finding an architect, designer or builder who understands the huge benefits of natural air flow, you can begin the process of controlling your comfort by installing Ply-foil Radiant Barrier Insulation underneath your roof panel.

This will dramatically reduce radiated heat in your home, add energy efficiency to your property while reducing your utility bills.

Most building materials, tend to absorb a large percentage of the radiant energy they encounter as heat. However, tests have shown that one sheet of Plyco Plyfoil Insulation in the center of an airspace reflects 97% of radiant heat. This means heat rays pass through it at a rate of only 3%.

Properly installed and taped, it provides an excellent vapor barrier, assists in limiting condensation and features the top classification of burn and flame spread ratings.  It does not absorb water and does not mildew.

ECMIL recommends Ply-foil as part of complete roof sheeting solutions.
Recent temperatures have moved this material from accessory to necessity.

Ply-foil Radiant Barrier Insulation will change the overall temperature in your home.


For those with lowered ceilings and the inevitable hot house loft, it is more than likely that your outside eaves, or overhangs are boarded, but can access the ceiling void of your home. If this is so, then the installation of Soffit Vents will release large amounts of radiated heat from your loft area, while allowing outside air to circulate. These vents can be opened and closed manually (seasonal), can have removable screens to prevent unwelcome intruders into your attic space and come in many shapes and sizes.

To calculate how much soffit vent space you will require:

  • Work out the square footage of your attic space.
  • Divide this figure by 150 - As a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space.

The vent square footage should then be divided equally on opposite sides of the roof to balance inflow and outflow of air.


Wall vents, above doors or windows can make a tremendous difference, especially when a house needs to be closed up during bad weather.  'A Gable Vent' is the answer to the comment "...ventilation to release the radiated heat from the roof vault." Often in a diamond or circular configuration, this vent is located high up the gable wall, at either end of the building and was the standard means by which most gable roof timber structures were cooled in earlier times.

For the more adventurous among us, keeping the direct sun off the walls of a house, works wonders in conjunction with the above suggestions. I am suggesting a simple roofed porch or walkway running the length of an extremely sun drenched wall. This can make a world of difference to indoor temperatures.

These are some cost effective choices. It is always easier to include a ventilation plan from the outset of the house design. It then becomes integral to every design decision made. But the truth is that there are many more homes which need to convert to a cooling plan than new houses with the advantage of considering this from the outset.

Discuss this with your architectural and construction professional and embark on a cooling strategy,
customized for your home.

Ask your ECMIL sales representative about Plyfoil when you decide on a new or updated roof. When you experience its effects, it will give you a comfortable temperature to truly reflect upon!


energy efficient, installation friendly & cost effective

Find out more ...

NB. This article is for general information purposes only and is meant as an incentive to the reader, who should then research and seek advice from their architectural and construction professionals to confirm that the ideas expressed are possible within the building codes of their territory or within the limitations of their home's architecture. ECMIL only recommends their own products and third party products which they supply, as part of their company's roofing solutions to customers.

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