Product: Reach Barrier Silvertanium Reflective Attic Insulation
Best Place to buy:
Home Depot:4 ft. x 250 ft. Silvertanium Radiant Barrier Insulation
Specifications: comes in 4ft. x 250 ft. Reflective 95%; Emissivity <0.05
Pros: light weight; easy to install; made in the USA from recycle material.
Cons: Typically not sold in store, you have to order it online.
My Rating: 10 out of 10
Reach Barrier Silvertanium Reflective Attic Insulation Product Overview
Silvertanium from Reachbarrier is a low-e product designed to be part of an attic insulation system though it can be used in other parts of our house as well. It is a double sided reflective foil with micro perforations to allow water vapor to pass through. It reflect 95% for infrared and has an emissivity of 0.05 making it a low-e material. It comes in a 4 foot by 250 foot roll that weights about 20 pounds. You can cut it with regular scissor but it resisting tearing and puncturing. The basic idea is you roll it out and staple a section to the under side of your rafters so it will reflect the radiant heat from your roof in the summer. You can alternately or additional lay it over your attic insulation. This will reflect the radiant heat in the attic in the summer or reflect radiant heat from your house in the winter. The very small evenly place holes allows water vapor to pass through but blocks air flow so placing it over blown in or batt insulation will minimize convective looping. It can also be used under the floor joist in a basement or craw space and over wall insulation in the basement. Since it is not a vapor barrier it is not recommended for exterior walls
While the primary purpose of this insulation to is to reflect radiant heat (infrared) and/or have a low emissivity if installed with air gaps it does an R value as well. The R value varies considerable based on where it is installed whether that be attic rafter or joist or basement walls or floor joist; and the air gap on one or both sides and if those air gaps are ventilated or unventilated.
Applications of Silvertanium
Installing a radiant barrier in the rafters of an attic is the most typical applications for Silvertanium. Roofs get very hot, up to around 160 degrees F, in the summer with the underside around 140F or more. The roof sheathing radiates the heat which can move through typical attic insulation and heat the inside of the top floor. A radiant barrier will typical reflect over 90% of that heat back. If you have a double sided radiant barrier like Reach Barrier Silvertanium it will have a low E of .05 so only a small amount of the radiant and conductive heat the barrier absorbs is transmitted into the attic space. This can be a big energy saving for not much cost, around 17 cents per square foot.
In the winter what heat that makes it through your hopefully good attic insulation will be reflect back or emitted out more slowly.
Alternately or in addition to the attic rafters you could put the radiant barrier over the insulation on the attic floor. If you have soffit and ridge vents this is really the way to go. The venting will allow convection to take away heat and the radiant barrier will reflect heat from above for summer and below for winter. Additionally the barrier will stop convective looping which is a real problem with blown in insulation typically used in attics. As a side note batt insulation has much lower convective looping than blown in insulation but can still benefit from a radiate barrier.
Walls In Basement
In the basement the radiant barrier should be installed over a rigid conductive insulator such as Roxul Rockboard(R) or Owen Corning FOAMULAR 250. Ideally you install the rigid insulation against the basement wall; then put furring strips and staple the radiant barrier to the furring strip; then install furring strip over that; finally install our sheetrock. If you are not finishing your basement then stop at the radiant barrier. It is important to have air gaps on at lease one if not both sides for the radiant barrier foil otherwise it will start conducting versus reflecting.
Under side of floor joists.
Another application is to install a radiant barrier on the bottom of floor joists. This can give you a R value of over 8 for vented and over 13 for unvented.
- Radiant barrier.
- Convective Looping Green Building Advisor.
- Convective loops, Air Leaks & Heat Loss Analysis for buildings
- Reach barrier.