FHB Logo Facebook LinkedIn Email Pinterest Twitter X Instagram Tiktok YouTube Plus Icon Close Icon Navigation Search Icon Navigation Search Icon Arrow Down Icon Video Guide Icon Article Guide Icon Modal Close Icon Guide Search Icon Skip to content
Subscribe
Log In
  • How-To
  • Design
  • Tools & Materials
  • Restoration
  • Videos
  • Blogs
  • Forum
  • Magazine
  • Members
  • FHB House
  • Podcast
Log In

Discussion Forum

Discussion Forum

Corrugated Plastic Roofing Question

asmith | Posted in General Discussion on February 1, 2006 07:22am

Hey Guys,

This is a little different from my normal cup of tea…

A terrific older couple from my church have some leaks in a clear corrugated plastic roof over a screened porch and I would like to repair it for them.

The roof appears to be about a 1 to 3 in 12 pitch and the longitudinal overlaps are one corrugation with clear (silicone) caulk in the overlaps. They are attached to factory cut corrugated wood purlns with rubber-grommeted machine screws.

I was there when it was *barely* raining yet water was coming through. I couldn’t pinpoint the leaks. Screws? Overlaps? Failed Silicone?

Do any of you have any experience at all with this stuff?

Thanks!

a.

Reply
  • X
  • facebook
  • linkedin
  • pinterest
  • email
  • add to favorites Log in or Sign up to save your favorite articles

Replies

  1. piko | Feb 01, 2006 08:29am | #1

    Were the screws in the valleys? Anyway, try tightening the screws first - the gaskets weaken with exposure. Depending on the thermal movement, the holes may have elongated and not be covered by the gaskets.

    You will be able to tell it the silicone has failed/doesn't work, 'cos there'll be a line where the rain comes thru.

    On the other hand, it may be condensation dripping off...

    All the best...

    To those who know - this may be obvious. To those who don't - I hope I've helped.

     

    1. asmith | Feb 02, 2006 02:21am | #2

      I'll go back and look at these things. I might give it the garden hose test.Thanks!
      a.

      1. piko | Feb 02, 2006 04:34am | #3

        Good idea - may I suggest that you do it along the first 2 feet, then the next, etc...you'll be able to pin-point better that way.All the best...

        To those who know - this may be obvious. To those who don't - I hope I've helped.

         

        1. asmith | Feb 03, 2006 07:01am | #5

          <<<do it along the first 2 feet, then the next, etc.>>>That's good advice.Thanks.

  2. DanH | Feb 02, 2006 06:22am | #4

    Our upper deck has this sort of roof. It's actually quite trouble-free, but can leak under the wrong conditions.

    First check the gasket-head nails/screws -- look for any that have worked loose up or had their heads pop off. Note that all the nails SHOULD be on top of the ridges, not in the valleys.

    The lap of adjacent sheets should be one full ripple (or sometimes one-and-a-half), with the edge of the top sheet ending in the valley of the sheet below. If the edge ends on top of a ridge then the sheets were installed upside-down or lapped the wrong way.

    It should not be necessary to seal between adjacent sheets -- the overlap should suffice for all but extreme cases of wind-blown rain. Sealant in the wrong place could actually cause leaks by damming drainage.

    A 2:12 slope is about the lowest you can expect the lapped seams to work right. If it's a real low slope there may not be much you can do.

    If ignorance is bliss why aren't more people

    happy?

    1. asmith | Feb 03, 2006 07:05am | #6

      Thanks for the info. Good tips. I'll try to take a look at it Saturday.

Log in or create an account to post a comment.

Sign up Log in

Become a member and get full access to FineHomebuilding.com

Video Shorts

Categories

  • Business
  • Code Questions
  • Construction Techniques
  • Energy, Heating & Insulation
  • General Discussion
  • Help/Work Wanted
  • Photo Gallery
  • Reader Classified
  • Tools for Home Building

Discussion Forum

Recent Posts and Replies

  • |
  • |
  • |
  • |
  • |
  • |
View More Create Post

Up Next

Video Shorts

Featured Story

FHB Podcast Segment: Repairing an Old Home While Maintaining Its Integrity

Learn about different approaches to making updates and repairs to older homes with historic charm.

Featured Video

SawStop's Portable Tablesaw is Bigger and Better Than Before

The 10-in. Jobsite Saw PRO has a wider table, a new dust-control port, and a more versatile fence, along with the same reliable safety mechanism included in all SawStop tablesaws.

Related Stories

  • Tools and Gear for the Moms Who Get it Done
  • Beat the Heat: Cool Innovations
  • A Practical Approach to Exterior Insulation
  • Making and Installing Wood Wall Paneling

Highlights

Fine Homebuilding All Access
Fine Homebuilding Podcast
Tool Tech
Plus, get an extra 20% off with code GIFT20

"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Fine Homebuilding Magazine

  • Issue 331 - June 2025
    • A More Resilient Roof
    • Tool Test: You Need a Drywall Sander
    • Ducted vs. Ductless Heat Pumps
  • Issue 330 - April/May 2025
    • Deck Details for Durability
    • FAQs on HPWHs
    • 10 Tips for a Long-Lasting Paint Job
  • Issue 329 - Feb/Mar 2025
    • Smart Foundation for a Small Addition
    • A Kominka Comes West
    • Making Small Kitchens Work
  • Issue 328 - Dec/Jan 2024
    • How a Pro Replaces Columns
    • Passive House 3.0
    • Tool Test: Compact Line Lasers
  • Issue 327 - November 2024
    • Repairing Damaged Walls and Ceilings
    • Plumbing Protection
    • Talking Shop

Fine Home Building

Newsletter Sign-up

  • Fine Homebuilding

    Home building tips, offers, and expert advice in your inbox.

  • Green Building Advisor

    Building science and energy efficiency advice, plus special offers, in your inbox.

  • Old House Journal

    Repair, renovation, and restoration tips, plus special offers, in your inbox.

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters

Follow

  • Fine Homebuilding

    Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.

    Start Free Trial Now
    • Facebook
    • Instagram
    • X
    • LinkedIn
  • GBA Prime

    Get instant access to the latest developments in green building, research, and reports from the field.

    Start Free Trial Now
    • Facebook
    • YouTube
  • Old House Journal

    Learn how to restore, repair, update, and decorate your home.

    Subscribe Now
    • Facebook
    • Instagram
    • X
  • Fine Homebuilding

    Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.

    Start Free Trial Now
    • Facebook
    • Instagram
    • X
    • LinkedIn
  • GBA Prime

    Get instant access to the latest developments in green building, research, and reports from the field.

    Start Free Trial Now
    • Facebook
    • YouTube
  • Old House Journal

    Learn how to restore, repair, update, and decorate your home.

    Subscribe Now
    • Facebook
    • Instagram
    • X

Membership & Magazine

  • Online Archive
  • Start Free Trial
  • Magazine Subscription
  • Magazine Renewal
  • Gift a Subscription
  • Customer Support
  • Privacy Preferences
  • About
  • Contact
  • Advertise
  • Careers
  • Terms of Use
  • Site Map
  • Do not sell or share my information
  • Privacy Policy
  • Accessibility
  • California Privacy Rights

© 2025 Active Interest Media. All rights reserved.

Fine Homebuilding receives a commission for items purchased through links on this site, including Amazon Associates and other affiliate advertising programs.

  • Home Group
  • Antique Trader
  • Arts & Crafts Homes
  • Bank Note Reporter
  • Cabin Life
  • Cuisine at Home
  • Fine Gardening
  • Fine Woodworking
  • Green Building Advisor
  • Garden Gate
  • Horticulture
  • Keep Craft Alive
  • Log Home Living
  • Military Trader/Vehicles
  • Numismatic News
  • Numismaster
  • Old Cars Weekly
  • Old House Journal
  • Period Homes
  • Popular Woodworking
  • Script
  • ShopNotes
  • Sports Collectors Digest
  • Threads
  • Timber Home Living
  • Traditional Building
  • Woodsmith
  • World Coin News
  • Writer's Digest
Active Interest Media logo
X
X
This is a dialog window which overlays the main content of the page. The modal window is a 'site map' of the most critical areas of the site. Pressing the Escape (ESC) button will close the modal and bring you back to where you were on the page.

Main Menu

  • How-To
  • Design
  • Tools & Materials
  • Video
  • Blogs
  • Forum
  • Project Guides
  • Reader Projects
  • Magazine
  • Members
  • FHB House

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Popular Topics

  • Kitchens
  • Business
  • Bedrooms
  • Roofs
  • Architecture and Design
  • Green Building
  • Decks
  • Framing
  • Safety
  • Remodeling
  • Bathrooms
  • Windows
  • Tilework
  • Ceilings
  • HVAC

Magazine

  • Current Issue
  • Past Issues
  • Magazine Index
  • Subscribe
  • Online Archive
  • Author Guidelines

All Access

  • Member Home
  • Start Free Trial
  • Gift Membership

Online Learning

  • Courses
  • Project Guides
  • Reader Projects
  • Podcast

More

  • FHB Ambassadors
  • FHB House
  • Customer Support

Account

  • Log In
  • Join

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Follow

  • X
  • YouTube
  • instagram
  • facebook
  • pinterest
  • Tiktok

Join All Access

Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.

Start Your Free Trial

Subscribe

FHB Magazine

Start your subscription today and save up to 81%

Subscribe

Enjoy unlimited access to Fine Homebuilding. Join Now

Already a member? Log in

We hope you’ve enjoyed your free articles. To keep reading, become a member today.

Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.

Start your FREE trial

Already a member? Log in

Privacy Policy Update

We use cookies, pixels, script and other tracking technologies to analyze and improve our service, to improve and personalize content, and for advertising to you. We also share information about your use of our site with third-party social media, advertising and analytics partners. You can view our Privacy Policy here and our Terms of Use here.

Cookies

Analytics

These cookies help us track site metrics to improve our sites and provide a better user experience.

Advertising/Social Media

These cookies are used to serve advertisements aligned with your interests.

Essential

These cookies are required to provide basic functions like page navigation and access to secure areas of the website.

Delete My Data

Delete all cookies and associated data