What is an ice dam?
Ice dams form when warmth from inside the home melts the bottom layer of snow on the roof, sending water trickling down to the edge. Exposed to frigid air, it immediately refreezes, clogging gutters and causing the water behind it to pool up and find a path into the home below, usually through the shingles. Ice dams are more common in older or poorly insulated homes and those with low-pitch roofs. But even in newer homes, a new roof can leak if water runs backward in between the shingles.
Why is wind-driven rain a problem?
Wind-driven rain can cause sloped roof coverings to shift and lift. Rain can then be easily driven under the roof covering directly to the unprotected roof deck, where it causes leaks and damage to the inside of the home.
What is a roofing underlayment?
A roofing underlayment is typically a rubberized membrane that goes under
shingles to prevent water penetration. It is the one piece of a roofing
system that is expressly designed to be waterproof. Without a self-adhered
underlayment, water from wind-driven rain or ice dams can infiltrate under
your shingles and severely damage your roof—or even
worse, the inside of your home. Grace roofing underlayments, widely regarded
as the best in the industry, offer premium waterproofing protection. Non-adhered
roofing underlayments typically provide only water shedding protection
to the roof (not waterproofing as self-adhered underlayments do).
How do I know which Grace underlayment to use?
First, consider your climate and the kind of protection your home requires. Grace Ice & Water Shield is the best choice for maximum protection in areas of the country that experience snowy winters, which can often cause heavy or long-lasting ice dams. Grace Ice & Water Shield also offers sufficient protection in areas where winters are generally mild but still experience wind-driven rain, or where code-based minimum standards of protection are required. If, however, you live in a climate where your roof will be subjected to very high temperatures for extended periods of time, then Grace Ultra is the appropriate choice.
What types of roof coverings can benefit from Grace underlayments?
You can use Grace underlayments for all commonly used roofing materials including asphalt shingles, slate, tile and metal. For metal roofs, first check with the manufacturer for any special requirements.
How long can Grace underlayments be exposed?
Grace underlayments are not meant to be left permanently exposed to the sun. In general, the membrane should be covered with the final roof covering as soon as possible. If you experience construction delays or weather problems, however, Grace underlayments may be left exposed for the following amount of time:
Grace Underlayment
Grace Ultra
Grace Ice & Water Shield
Grace Select
Grace Basik®
Grace Tri-flex 30 |
|
Maximum Exposure Period
60 Days
30 Days
30 Days
30 Days
180 Days |
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Are Grace underlayments vapor barriers?
Yes. Grace Ice & Water Shield, Grace Select and Grace Ultra are all vapor barriers. Vapor barriers help maintain proper ventilation, which is important for all types of roofs. Ventilation is especially critical for certain kinds of metal roofs, such as those made from zinc, which are particularly susceptible to corrosion.
What is the difference between Grace Ice & Water Shield® and Grace Select?
Grace Ice & Water Shield is designed to offer maximum protection from
leaks caused by ice dams in all climates, clearly surpassing many of the
minimum standards of performance set by ASTM (American Society for Testing
and Materials), ICBO (International Conference of Building Officials) and
SBCCI (Southern Building Code Congress International). Although Grace Ice & Water
Shield is recognized as the premium underlayment on the market today, some
homes do not demand such high performance. If the home is in a mild climate,
or if the specification is for minimum code standards only, then Grace
Select is sufficient. Grace Select is also thinner (25 mil vs. 40 mil)
and lighter than Grace Ice & Water Shield.
Can I put Grace Ice & Water Shield on my whole roof?
Yes. It can be safely applied to the entire roof.
Does Grace Select meet building codes?
Yes. Grace Select meets the key performance standards prescribed by ASTM and ICBO for fully adhered underlayments in severe climates. (See ICBO Evaluation Services Report No. 3997). Grace Select also has a UL (Underwriters Laboratories) Class A fire classification for fiberglass shingles, and a Class C for organic felt shingles.
What is the difference between Grace & Water Shield and Grace Ultra?
The main difference is in the type of adhesives. Grace Ice & Water Shield uses an adhesive based on SBS rubber, whereas Grace Ultra uses one based on butyl rubber. Simply stated, butyl rubber offers exceptional stability at high temperatures. In some roofing applications, such as those in the desert southwest, rooftops can get so hot that SBS-based adhesives can start to melt. Butyl rubber-based membranes remain stable for long periods of time even at extreme rooftop temperatures. This means that Grace Ultra may be left exposed to the sun for up to 60 days.
Which Grace product should I use for waterproofing other areas, such as windows and doors?
Grace Vycor® Plus Self-Adhered Flashing provides premium exterior protection against moisture, air and water leaks. Flashings seal a wall at its most vulnerable points, such as window and door openings, corner walls, decks and under stucco finishes. Grace Vycor Plus is 25 mil thick and is available rolls of 4, 6, 9 or 12 inches. It should not be installed on roofs.
What is RICORD and what does it do?
RIPCORD is Grace's unique patented technology that provides "split release on demand". RIPCORD is a cord, embedded in the adhesive layer, allowing the split of the release paper in half. RIPCORD simplifies the flashing installation procedures and offers superior flashing performance, by enabling proper integration of the flashing with other key moisture protection elements of the wall.
How much Grace Ice & Water Shield do I need for a specific roof pitch?
Grace recommends that the Grace Ice & Water Shield is extended a min. of 24"" beyond the inside face of the exterior wall line of a building and should extend from the eave above the highest expected ice damn. Check local codes and regulations as they may vary. If installing full coverage of Grace Ice & Water Shield, use same roof area calculation for finished roof covering.
What should I do to cover Grace Underlayments to minimize exposure?
If the Grace self-adhered underlayment is in danger of exceeding the maximum epxosure limitation, the membrane should be covered. Grace Triflex 30 can be applied over the membrane, provided it is acceptable for use in the specific roofing application (i.e. roof design and region) to extend the exposure limit.
Can Grace Ice & Water Shield be applied over roofing felt?
Grace Ice & Water Shield is intended to be applied directly to the structural roof deck and does not need to cover roofing felt except where the two materials overlap. Laps between Ice & Water Shield and felt should be made to shed water.
How do I flash a chimney?
Refer to Grace Roof Detail Membrane product information.
How do I flashing a skylight?
Refer to Grace Roof Detail Membrane product information.
Do I need roofing felt in addition to Grace Ice & Water Shield?
Grace Ice & Water Shield self adhered underlayment should be used in all critical roofing applications. Depending on the climate, a full roof coverage with Ice & Water Shield should be considered. For the rest of the roof, Grace Triflex 30 can be applied as a water-shedding roofing underlayment, except for the cases of full Ice & Water Shield coverage.
What is the difference between Grace Triflex and Grace Ice & Water shield?
Grace Tri-Flex 30 synthetic roofing underlayment is a premium water-shedding underlayment. Grace Tri-Flex 30 is not designed to protect against standing water or water moving upslope resulting from factors such as accumulated snow, ice, wind-driven rain, or debris. For protection from standing water or water moving upslope, it is recommended that Grace Ice & Water Shield self-adhered underlayment be used.
How do I know which Grace Underlayment to use?
The Grace Underlayments Product Selection Matrix, found on all Grace underlayment product data sheets, provides guidence in selecting the proper underlayment for various application conditons.
Contact a Grace representative for more information.
Do I use Triflex or Grace Ice & Water Shield or both?
Grace Tri-Flex 30 synthetic roofing underlayment is a premium water-shedding underlayment. Grace Tri-Flex 30 is not designed to protect against standing water or water moving "upslope" resulting from factors such as accumulated snow, ice, wind-driven rain, or debris. For protection from standing water or water moving "upslope", it is recommended that Grace Ice & Water Shield self-adhered underlayment be used. These two types of underlaymetns can be used independent of each other or together to provide a premium system, depending on the design needs.
Can my roof breathe if entirely covered by Grace Ice & Water Shield?
Grace underlayments are excellent air and vapor barriers. When used in full roof coverage applications, adequate ventilation must be provided to avoid condensation problems within the roof structure or the attic space.
Which underlayment is recommended for flat roofs?
Grace underlayments are intended for use on sloped roofs and are not intended to be used as waterproofing on flat roofs.
What is the difference between Grace Triflex and 30lb roofing felt?
Grace Tri-Flex 30 synthetic roofing underlayment is a premium water-shedding underlayment. Unlike conventional roofing felts, it does not absorb water and can be used to "dry-in" roofs for up to 6 months before the primary roof coverings are applied. It is stronger than #30 felt and withstands high wind conditions; it is lighter than #30 felt and covers more area. However, as a water-shedding underlayment, the performance of the product relies on the ability of sloped roofs to shed water.
What size rolls do Grace Ice & Water Shield, Ultra, Select, Basik and Triflex come in?
| Product |
|
Width |
|
Length |
| Grace Ice & Water Shield |
|
3' |
|
75' & 36' |
| Grace Ultra |
|
2' 10" |
|
70' |
| Grace Select |
|
3' |
|
65' |
| Grace Basik |
|
3' |
|
50' |
| Triflex |
|
41.5" |
|
300' & 150' |
| Roof Detail Membrane |
|
9" & 18"
|
|
50' |
How do I flash drip edges?
The metal drip edge or wood starter shingle should be placed over the membrane as shown in standard Grace detail drawings. The Grace self-adhered underlayments should not be installed over cedar shingles. Refer to eave application details at www.graceconstruction.com for more information.
Where can I find Grace roofing underlayments?
Click here to locate a distributor near you.
How do I become a distributor / stocking location for your products?
Click here to locate a sales representative near you.
Where can I get pricing information for your products?
Click here to locate a distibutor near you.
Do you have any sales representative in my area that I can contact?
Click here to locate a sales representative near you.
Where can I get warranty information on your products?
Warranty is printed on product packaging. If you need further information, call 866-333-3726.
Where can I call for technical / application questions?
For technical support call 866-333-3726.
Where can I get Material Safety Data Sheets (MSDS)?
Click
here to locate an MSDS.
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