DuPont Flashing Tape 9″ x 75′ — Butyl Self-Adhered Window Sill Flashing (1 Roll)

Description

What it is — and when 9″ is the right width

DuPont Flashing Tape is a self-adhered flashing made with a 100% butyl adhesive layer, engineered to seal the joint between the rough opening and the water-resistive barrier. No asphalt, no modified bitumen — pure butyl on a polypropylene film, with a heavy-duty split release liner so you can set it in two passes without wrinkles.

The width decides the job:

• 4″ — sheathing seams, narrow jambs, trim details
• 6″ — standard window jambs and heads
• 9″ — window sills and mid-size openings. The width most crews reach for on sill pans, where the lap has to run up the jamb and out onto the sheathing
• 12″ — wide sills, door pan flashing, large openings

If you are flashing standard residential windows, 9″ on the sill and 6″ on the jambs and head is the combination that covers most of a house.

Specifications

Adhesive	100% butyl (no asphalt or modified bitumen)
Backing	Polypropylene film
Release liner	Heavy-duty siliconized paper, split design
Size	9 in × 75 ft (1 roll)
Application temperature	Down to 25°F (-4°C)
UV exposure	Up to 120 days
Primer	Not required on most common building materials
Factory carton	4 rolls
Condition	New, factory sealed

Standards and warranty

AAMA 711	Class A, Level 3 — highest classification
ASTM E1677	Assembly air leakage < 0.04 cfm/ft²
ASTM E331	No water leakage at 300 Pa (6.24 psf)
ASTM E96	Water vapor permeability < 1 perm

Backed by DuPont 10-Year Limited Warranties when installed as part of the Tyvek® WRB system.

Installation notes

You need:

• A clean, dry, frost-free surface
• Rough sill framing level or sloped slightly to the exterior
• A chemically compatible primer over concrete, masonry, and glass-mat exterior gypsum sheathing

Do not use it for:

• Through-wall flashing applications
• Installing over cap fasteners

How many rolls you need

75 ft per roll. Quick math:

• Sill pans on standard 3 ft windows (about 5 ft per sill with laps): roughly 15 sills per roll
• Full perimeter of a 3 ft × 5 ft window (about 16 ft with laps): roughly 4 windows per roll

For a typical single-family house with 12 to 15 openings, one roll of 9″ covers the sills with room to spare. Most crews pair it with 6″ for the jambs and heads.

Same roll, lower price: clearance stock

We keep a few rolls whose packaging took a beating in storage. The tape inside is factory-sealed and carries the same DuPont 10-year limited warranty as a new roll — only the carton looks rough.

• DuPont Flashing Tape 9″ × 75 ft — clearance — $54.99 instead of $66.99, while stock lasts

Contractor and volume pricing

The factory carton is 4 rolls. Call (832) 463-7946 or email sales@85builders.com with your quantity and the job-site ZIP code and we will send carton pricing the same business day.

We accept Texas resale certificates for tax-exempt purchases.

Frequently asked questions

Is this genuine DuPont?

Yes. New, factory-sealed product in original DuPont packaging. Not generic, not repackaged.

Do I need a primer?

On most common building materials, no. You do need one over concrete, masonry, and glass-mat exterior gypsum sheathing — use a chemically compatible primer.

Can I install it in cold weather?

Down to 25°F (-4°C). Below that the butyl will not bond reliably and you will get failures.

How long can it stay exposed before the wall is closed in?

120 days of UV exposure. If the schedule runs longer than that, it needs to be covered.

Can I use it for through-wall flashing?

No. DuPont specifically excludes that application.

How fast does it ship?

We ship next business day from Cypress, TX.

Also Available

Need a wider roll? See DuPont Flashing Tape 12″ x 75′ for sill pans, wide headers, and commercial window openings.