With steel roofing for barndominiums, shouses and post frame (pole) buildings comes condensation.
When atmospheric conditions (in this case temperature and humidity) reach dew point, air’s vapor is able to condense to objects colder than surrounding air temperature. Once vapor condensing occurs, droplets are formed on cool surfaces. This is partly why warming a vehicle’s windshield with a defroster can prevent glass ‘fogging’.
When a building’s interior air meets these conditions, air vapor will condense to cool surfaces. Steel roofing cooled by exterior air temperature often provides this surface. Droplets formed will combine as they contact one another, continuing to do so until they are too large to be supported by surface tension. At this point, dripping will occur, essentially raining on your structure’s contents.
Commonly (when addressed at all during construction) solutions to this problem have often involved creating a thermal break. A thermal break reduces contact between a structure’s warm interior air and cooler metal roofing, thereby reducing or eliminating overall condensation. Installing a reflective radiant barrier, often termed Vapor Barrier, involves laying rolls of faced ‘bubble wrap’ across your building’s purlins prior to roof steel installation. Ideal weather conditions are required for this as even a slight wind can make this a challenging or altogether impossible task. This can cause jobsite delays and may bring progress to a halt while a structure remains unprotected to weather. Even when ideal weather conditions are present, installing a reflective radiant barrier can be a very dangerous task, requiring builders to expose themselves to awkward material handling on a building’s bare roof framing. These risks and delays often generate additional costs for both owners and builders, but have often been necessary with reflective radiant barrier being the only relatively affordable option to prevent interior dripping.
New materials and production methods offer a better solution. Utilizing polyester fabric’s absorption characteristics and their integral application during roll-forming, most better quality steel roofing roll formers offer a ready-to-install roofing panel with integral drip-protection. I.C.C. is a pre-applied solution reaching jobsites ready for immediate installation. Delays and increased jobsite workload caused by problems associated with radiant reflective barriers are eliminated by this product. Also, due to this solution’s simplicity, panels with I.C.C. install using the same methods, fasteners and time similar panel-only installations require. No changes to installation processes are necessary, with an exception of time and effort saved.
It works because this polyester membrane simply retains liquid until atmospheric conditions allow it to be re-evaporated. This is because polyester is hydrophilic, meaning water is attracted to it. It acts as a wick, harmlessly absorbing condensing vapor. Rather than preventing condensation, it provides an absorbent layer to detain condensing vapor until it can re-evaporate as temperatures increase and humidity decreases.
What product do you suggest for the radiant reflective barrier? I keep reading what NOT to use and not what the product is.
Georgeana’s building has roof steel with a factory applied Integral Condensation Control, not sure where you intend to use a radiant reflective barrier.
With the I.C.C. product installed on the roof panals, can closed cell spray foam be applied directly over this product?
No, you want to closed cell spray foam directly to bare steel.