FlowGuard Slip Under Shingle Gutter Cover System Thermal Thaw Black

Our review of the FlowGuard Slip Under Shingle system finds it best suited for homeowners who want a long-lasting, low-maintenance gutter protection solution that resists rust and handles heavy rain and snow. Installed beneath shingles and mounted atop gutters, the FlowGuard's biggest selling point is durability:.018 heavy gauge painted aluminum and stainless steel fasteners mean it is built to last and backed by a 50 year warranty. For anyone tired of cleaning wet, slimy debris from gutters, this product delivers season-long protection when installed correctly.

Key Features

• Made in the USA: The entire system is manufactured in the US, offering quality control and domestic materials for dependable performance.
• Heavy gauge aluminum:.018 painted aluminum construction resists rust and deterioration, giving long-term durability under severe weather.
• Under shingle design: Mounts beneath shingles and anchors with included stainless steel twin thread pierce point zip screws for a permanent, wind-resistant fit.
• 3-point airflow design: Elevates wet leaves so airflow dries debris and light winds eventually remove buildup, helping keep gutters flowing.
• Easy to trim and join: Dual interlocking ends and a 45 degree drain hole pattern simplify cutting miter corners and creating continuous runs.
• 50 year warranty: A long manufacturers warranty provides peace of mind and signals confidence in the product's longevity.

Who It's For

This product is ideal for homeowners with standard residential roofs who want a permanent gutter guard that minimizes annual maintenance and performs in heavy rain, snow and wind. It suits DIYers comfortable cutting metal with tin snips and using a drill to fasten stainless steel screws.

It is not the best fit for those who cannot lift roof shingles or prefer a non-penetrating clip-on system, or for buyers needing decorative or seamless aluminum profiles for specialty gutter shapes not compatible with a slip-under design.

Pros & Cons

Pros

• Made from sturdy.018 heavy gauge painted aluminum that will not rust and stands up to weather.
• Under shingle installation with stainless steel fasteners creates a secure, permanent attachment resistant to wind and snow loads.
• 3-point design prevents wet debris from sticking and helps water drain even when partially covered.
• Includes screws and offers a 50 year warranty for long-term confidence.

Cons

• Installation requires access under shingles and basic metal cutting tools, so homeowners who avoid roof work may need professional help.

Specifications

Brand	Flexxpoint Gutter Cover, LLC.
Material	.018 painted aluminum
Length	204 ft total
Widths supported	5 in and 6 in gutters
Fasteners included	Stainless steel 1/2 in #8 twin thread pierce point zip screws
Design	Under shingle, 3-point airflow
Warranty	50 year manufacturers warranty

Our Verdict

FlowGuard Thermal Thaw Black is a durable, practical choice for homeowners seeking a permanent, low-maintenance gutter cover that handles heavy rain and snow. The heavy gauge aluminum, included stainless fasteners and long warranty make it good value for those able to do slip-under installation or willing to hire a pro.

Frequently Asked Questions

Will this fit my 5 in gutters?
Yes, FlowGuard is designed to work with both 5 in and 6 in standard residential gutters when installed as directed.

Are fasteners included?
Yes, stainless steel 1/2 in #8 twin thread pierce point zip screws are provided for permanent installation.

Does it require roof penetrations?
The under shingle mounting slides beneath shingles and secures to the roof edge; it requires access under the shingles but uses the provided fasteners rather than altering the gutter itself.