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

Leaky window , mold, help!

cdbeardie | Posted in Construction Techniques on March 14, 2009 09:03am

My husband and I were up at the family cabin, which is now almost 20 years old, putting down a new poly layer on the crawl space, when we discovered that there was a major leak under three , large, floor to ceiling homemade windows in the dining room (we didn’t make them;  we bought it like that).   Upon closer inspection, the caulk on the flat, cedar window sills wasn’t doing its job, and water leaked under the window into the insulation, framing, and finally into the crawl space.  (Just a side note:  If you’ve determined by now that we are both idiots for now redoing the flat cedar window sills – you are right!  We thought about it, and knew they should be replaced, and we didn’t do it because……we just didn’t.  Now, we’re regretting our inaction!!!) 

Anyway, so far, we’ve removed the drywall and insulation below the window, and we sprayed on and brushed in mold’/mildew killer everywhere there was leaking water and black or white mold showing.  Upon further inspection after treatment, there’s a 6″ length of 2×4 under the window which has rotted on the top 1/2 ‘ or so, a little of the particle board sheathing near that spot is also rotted.  Similarly, underneath that area in the crawl space, there’s some rotted subfloor – extending about2″ to 6″ or so x 6″ long.  (There’s cedar siding on the exterior.)  Now, we’re trying to figure out where to go from there.   On the “do it right”  side, our sense is to wait until spring, remove the window, siding around it, and flooring and sub floor back about a foot, and replace it all with good wood.  Then, there’s the “fix it” side, which, we think, would involve repeated treatment of the moldy areas until it’s virtually all gone, replacement of the rotten wood, spraying a sealer, and  replacing the sills with boards cut at an angle so future moisture doesn’t get inside. 

We appreciate any suggestions.

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

Replies

  1. Danno | Mar 14, 2009 09:12pm | #1

    Your plan sounds like a good one to me. Kind of crazy to open things up now in the cold and do a rush job and not do it well. About the only thing I'd do now is put up a temporary plastic sheet or something to keep the water out and from pooling on the sill and wait for better weather.

    1. cdbeardie | Mar 14, 2009 09:23pm | #2

      We did take out the old caulk and put in new caulk AND also put another layer of angled bottom window sills above the old ones, and caulked those.  It has been dry so far.  So, would you do the whole big take out the window fix, or the smaller fix?

       

      Thanks!

      1. Danno | Mar 14, 2009 10:18pm | #3

        I gess I'd need to see it, BUT, if your fix is working and no more water is coming in, and the window itself has not rotted (other than the sill you fixed), I would be inclined to leave it and see. I know it'd be a pain to fix the rest (sistering good studs to old and so on) and then have to open it back up later if more leaks occurred, but...I'm not a fan of spending money I may not absolutely need to spend, and for me, my labor is free!

        You may want to fix with sistered studs and so on and even new insulation, and then screw something like prefinished "wood" paneling under the window and leave that for a year to make sure everything is fine (while still having fairly easy access to the inside of the wall). If everything is copasthetic, fasten the paneling more permanently or take it off and drywall.

        Even if it leaks again, (while you still have the wall panel allowing access) you should see evidence of it before it gets bad enough to require opening the floor up and replacing joists and stuff again.

        I have found that Great Stuff works well to insulate under formerly leaking windows (though it can take quite a bit--and I had already put in drywall before I squirted it in through holes and so couldn't tell when to stop--so when it expanded, it bowed the drywall--you don't want that to happen! If you foam it in before replacing the drywall, should be no problem--rasp down the x.s. before you drywall. Or just use fiberglass.

      2. Danno | Mar 14, 2009 10:21pm | #4

        One more thing; caulk may work, just check it annually to make sure it's still there and not cracking or pulling away. Better would be to put in flashing under it. The self adhering rubberized stuff is good (Vycor). But if it wasn't flashed, just caulk may be okay, but, like I said, check it often for potential leaks.

  2. Piffin | Mar 14, 2009 10:54pm | #5

    Kind of depends how many times you want to go through this

     

     

    Welcome to the
    Taunton University of
    Knowledge FHB Campus at Breaktime.
     where ...
    Excellence is its own reward!

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 Summit 2025 — Design, Build, Business

Join some of the most experienced and recognized building professionals for two days of presentations, panel discussions, networking, and more.

Featured Video

Builder’s Advocate: An Interview With Viewrail

Learn more about affordable, modern floating stairs, from design to manufacturing to installation.

Related Stories

  • Podcast Episode 686: Brick Steps, Ground-Source Heat Pumps, and Greenhouses in Nova Scotia
  • FHB Podcast Segment: Efficient HVAC for a New Build
  • Affordable Scans, Accurate Plans
  • FHB Summit 2025 — Design, Build, Business

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 70%

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