Synthetic Roofing Roofing FAQ

General  Installation  Fasteners  PSU30 Self Adhered

General FAQ Section

Q. What types of roofing materials can I use synthetic roofing underlayment with?

A. See our product selection guide here

Q. Do Titanium and RhinoRoof underlayments meet ASTM D226 standards?

A. Yes,all of our synthetic underlayments meet and exeed the testing requirements of ASTM D226. Same goes for ASTM4869.

Q. Can Titanium underlaymants contribute to a buildings LEED® points?

A. Yes, Titanium underlayments contribute to LEED points. More information on Titanium and LEED point can be found here

Q. Where can I find the building code listings for Titanium underlayments?

A. Follow the links below to go to the building code listing for the product that you are using. Printable PDF downloads are available from each section.

Q. Can I print my company logo onto Titanium or RhinoRoof underlayments?

A. Dual Logo printing programs are available for: UDL25, UDL30, UDL50 & RhinoRoof U15/U20.

Q. Where can I buy Titanium Synthetic Roofing Underlayments?

A. Click here to locate your nearest roofing distributor. Alternatively, ask for it at your nearest roofing products distributor or lumber yard.

Q. Why should I use synthetic underlayments instead of traditional felt papers?

  • Felt papers can tear easily whereas Titanium is a high strength coated woven construction (20-25 times stronger than 30lb felt)
  • Felt does not have a mechanical slip resistant feature like Titanium which has a patented SURE-FOOT® nodular slip resistant walking surface
  • Felt becomes brittle within days of UV exposure whereas Titanium can be left exposed for up to 6 months
  • Felt leaches oil in the heat and cracks in the cold whereas Titanium UDL's remain flexible from -40°F to 240°F
  • Felt papers are susceptible to mold growth whereas Titanium is completely inert to mold
  • Felt paper is prone to "blow-offs" in windy conditions whereas Titanium's high strength coated woven construction holds fast even in extreme conditions thereby protecting your roof from leaks and water
  • Felts are not covered by warranties whereas Titanium products have a Lifetime* Warranty [*Click here for Lifetime warranty details]
  • Felt only comes in heavy 36" wide rolls whereas Titanium UDL rolls are up to 8 times lighter and 48" wide (This makes installation faster with fewer laps)
  • Felt comes in 2 or 4 square rolls whereas Titanium is available in 10 gross square rolls
  • A 5,000 square foot job requires 25 rolls of #30 felt whereas with Titanium you would only requires 5.3 rolls.
  • Felt paper is not recyclable whereas Titanium UDL products are made partially from recycled material and are 100% recyclable (where facilities exist)

Q. What approvals / certifications / building code approvals do InterWrap underlayments comply with?

A. Exceeds all the underlayment standards. See product code listings links below:

Q. Are Titanium underlayments breathable?

A. Titanium underlayments are classified as an air, water and vapor barrier with a permeability rating based on ASTM E96 of approximately .06 perms.

Q. If the product is an 'air water & vapor barrier' - can you apply on a wet or damp roof? Will it trap/prevent moisture from drying out/escaping?

A. No. Installation instructions require that it be installed over a clean and dry deck. If installed over a wet deck, it could trap the moisture causing premature rot of the deck over time.

Q. What is Titanium product made of?

A. All UDL's are a 100% polypropylene coated woven material, certified minimum of 20% reclaimed content – contribute to LEED points and are 100% recyclable, recycle symbol #5

Q. Is Titanium product flammable?

A. Products qualifies for a Class A under metal, tile, slate, fibreglass mat based asphalt shingles per ASTM 108

Q. What is meant by Titanium being inert to mold?

A. Titanium and RhinoRoof are completely unaffected by mold and do not contribute to mold growth.  Mold requires a food source to feed on (such as the paper in asphalt saturated felt underlayments) Titanium and RhinoRoof are 100% synthetic therefore mold cannot feed on it.  Mold may appear on the surface (Due to environmental conditions) but the product is completely unaffected by it.

Q. Do Titanium products have an R Rating?

A. R-value is a measure of thermal resistance used in the building and construction industry.  At this time none of InterWrap roofing underlayments have an R value.

Installation FAQ Section

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Q. Can I use Titanium underlayments on a low slope or flat roof?

A. Titanium underlayments are for use primarily under steep slope roofing types. Steep sloped roofs are defined as having a pitch greater than 4:12. For low sloped (defined as 2:12 to 4:12) or flat roof types follow your regional building codes.

Q. How do I install synthetic underlayments?

A. Our installation instructions are available in English, French & Spanish. Click on the underlayment you are using to go to the installation instructions for that product.

Q. What is a "Batten System"?

A. A Batten is normally a 1" x 2" x 48" wood strip (in a few areas 6' or 10'). Most tile roofing have a cleat at one end and the cleat rests against the batten so it does not slide down the roof. These applications are normally 6:12 or greater unless the regional building codes requires differently. When the battens are installed they are spaced approx. 2 inches apart, end to end to allow water through.

Q. Can Titanium be put on top of felt?

A. Prefer installation applied to a clean roofing deck with no protrusions or voids- but yes"…. follow the surface preparation in our installation instructions.

Q. Can I use Titanium under clay tiles as I'm concerned about the foam application.

A.We are approved to be used with Polyset foam application for PSU30, UDL30 & UDL50.  These products are approved by Polyset foam & InterWrap with warranties in place.

Q. Can Titanium products be put on top of other ice damming products (not our PSU)?

A. YES, in many cases UDL is applied over PSU brands including ours to extend the UV exposure time or so the foot traffic effects the UDL not the PSU products.

Q. What is the minimum slope requirement for use of mechanically attached roofing underlayments?

A. InterWrap Titanium synthetics follow the same practice as for 30# felt.  In short they can be used in a single layer for steep slope 4/12 or greater. For low slope applications 2/12 to 4/12 it would require and minimum overlap of 50% coverage plus 1 inch.

Q. Why is there a minimum slope requirement?

A.Slope effects the speed at which water runs down the roof or overlaps.  If there is driving wind and rain water can get under the overlap and go beyond the 4 inch over lap and therefore water can get to the raw deck.

Q.  Is "Valley Flashing" required?

A. Yes, valleys should be prepared according to NRCA roofing practices, local codes or the primary roofing material manufacturer's recommendation. The use of UDL does not change good valley preparation and application.

Q. Can Titanium UDL be used with foam insulation?

A. Blown foam insulation by its very nature can make a roof attic not well ventilated.  Titanium installation instructions state to use "above a properly ventilated areas, as it is considered a vapor barrier". Titanium UDL underlayment can be used with a blown foam system if the attic area is part of a closed loop, meaning it is part of the HVAC system. Therefore the attic air temperature and moisture is being controlled by the HVAC mechanicals.

Q. Can Titanium UDL be used for wall application?

A. Titanium UDL products should only be used if the wall envelope design calls for an air water and vapor barrier.  IF a breathable product is specified then NO.

Fastners FAQ Section

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Q. Can staples be used to fasten UDL products?

A. Plastic cap staples with a 7/16” leg or greater are OK with UDL50 only.  Note: 3/8” head x 1” length ring shank nails preferred

Q. Why can't I use staples?

A. Use of staples results in poor hold down performance and the opportunity for staples to slice the membrane during traffic on the roof. The square edges of a staple act like a knife and with any movement, it could slice material and causing leakage. Plastic Cap Staples can be used with UDL50 only.

How many plastic cap nails are recommended per 10 Square roll of Titanium UDL?

A. If following the recommended nailing pattern as marked on the product this would require 1,750 nails. If covering the underlayment within 24 hours you can use every other anchoring point in the field. This would require 875 nails.

Q. Why is it recommended to use plastic cap nails?

A. The 1" diameter plastic cap helps increase hold down strength in high wind conditions.  If wind gets under the UDL underlayment and lifts the product against a 3/8" nail head (pillowing between anchoring points) the nail head can slice through the  product. Plastic cap nails provide some flex and a larger surface area to hold down product and are much less likely to pull through the UDL material.

Q. When using UDL30 under metal roof - do you have to use plastic cap nails?

A. The use of 3/8” head x 1” minimum length leg corrosion resistant roofing nails can be used without caps, if covered in 5 working days with the primary roofing material. (Ring shank nail leg is preferred)

PSU30 Self Adhered FAQ Section

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Q. Is Titanium PSU30 compatible with Dow Styrofoam?

A. No. the modified SBS asphalt will effect the Dow foam. Dow states the same.

Q. Can you apply PSU30 and/or UDLs on top of foam (no deck in between)?

A.  PSU30 can not be directly applied over Dow foam board. Yes UDL can be applied over foam board as long as the manufacturer of the foam board’s directions are followed. Be careful not to tighten down the anchoring devises on the foam board too tight as this will create water pounding.

Q. Can I put PSU30 over UDL?

A. Yes, this is frequently used in southern climates under tile. Our PSU30 has been approved and is a requirement for Miami Dade code installations. You cannot use this method for areas that require PSU30 ice damming protection.  In this case the PSU30 must be applied directly to the deck surface.

Q. Is PSU30 self sealing around nails?

A. PSU30 passes the ASTM D1970 Nail Sealability test.