if it is hot outside, the reflective part of your foil insulation must face outside. if it is freezing outside, the best orientation of the reflective part is inside. if you press the foil side of the insulation tight up against the wall (foil facing outward), the radiant barrier will not work.
If there is no dead air space, it doesn't matter which way the metallic side is facing.
When installing faced insulation, the facing should always point toward the interior, heated, or air-conditioned space. For example: On exterior walls, the facing should touch the drywall. In attics, the facing should point down toward the ceiling below.
Installing it
No air space means no thermal value. The reflective side must be facing downwards when in roofs, upwards when installed underneath a floor and inwards when installed in walls.
Foil has a shiny side and a dull side because of how it is manufactured. Unless you are using foil that's labeled non-stick, which does have a non-stick side, it does not matter what side you use. Both the shiny and dull sides can be used the same way to cook, freeze, and store food.
If you are wondering how to install the foil backed insulation on your walls here you have few tips to consider. if it is hot outside, the reflective part of your foil insulation must face outside. if it is freezing outside, the best orientation of the reflective part is inside.
Aluminum foil reflects heat from both its dull and shiny sides equally. While aluminum foil has a dull and shiny side, there is no difference in how either side reflects heat.
Install the Foilboard® GREEN rigid insulation panel to the external face of the studwork, ensuring the anti-glare side is facing out, measure the area you require. Tape all penetrations, joints and gaps using the Foilboard® green PVC tape, ensuring the stop of cold / hot air transfer.
One of the most important rules of insulation installation order is to install the thickest layer of insulation first, and then add thinner layers on top of it. This is because the thicker the insulation, the higher the R-value, and the more effective it is at preventing heat transfer.
In finished attic rooms with or without dormers, insulate (2A) between the studs of "knee" walls, (2B) between the studs and rafters of the exterior walls and the roof, (2C) and ceilings with unconditioned spaces above. (2D) Extend insulation into joist space to reduce air flows.
What is the pink fluffy stuff on the walls? The pink fluffy material is usually fiberglass insulation, commonly used for its safety and efficiency. It does not contain asbestos.
Vapor barrier materials are installed on the warm side of the insulation in a building assembly, as determined by climatic conditions. In warm climates, it will be on the exterior and in cold climates, it will be on the interior.
Faced insulation is ideal for spaces that have no existing insulation, such as exterior walls, attic ceilings, crawl spaces, and exterior basement walls. Please note that the proper way to install it is to have it installed facing outward or towards the person installing it.
Insulation boards are no exception to this rule, and it's important to leave an air gap between them and the surface they're installed on.
Foam Board or Rigid Foam
They provide good thermal resistance (up to 2 times greater than most other insulating materials of the same thickness), and reduce heat conduction through structural elements, like wood and steel studs.
(The general rule for insulation is that the facing always goes toward the conditioned space.)
By utilizing spray foam insulation on your building, you can significantly reduce both heating and cooling costs. Installing this material in a building without insulation will reduce costs by, on average, 50% right away.
It is important to leave a small air gap between boards and the mineral wool in order to stop damp forming. Remember that insulating between the joists will create a cold roof space as the heat is kept underneath the insulation like a blanket.
An air space must exist on a minimum of one side of the product (always on the reflective side (residential attic – preferably oriented facing down)). Radiant barriers by definition do not require an enclosed air space to provide benefit. This application (radiant barrier) is typically installed in a ventilated attic.
Q: Which way does the metallic side of R-Tech face? A: The metallic facer on R-Tech may provide additional R-Value if it is facing a dead air space of ¾˝ or more. If there is no dead air space, it does not matter which way the metallic side is facing.
Reynold's Kitchen, an aluminium foil manufacturer since 1947, says: "It's perfectly fine to place your food on either side so you can decide if you prefer to have the shiny or dull side facing out." It's simply a result of the manufacturing process. The performance of the foil is the same, whichever side you use.
People often ask which side of aluminum foil is nonstick. The answer is that it doesn't matter which side faces up or down when you're cooking with traditional aluminum foil—but if you're working with a specific nonstick variety, which has a protective coating, be sure to use the side recommended by the manufacturer.
Fun fact. Both sides are just as reflective as each other. The difference is that one reflects light and heat in the same direction like a mirror, while the other reflects it in random directions (technical term is random scatter). So no, no difference.