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
Sponsored Post
How-To

Sealing Gaps in Exterior Siding

Discover different exterior applications for a high-quality sealant.

Sponsored by GE sealants

We’ve teamed up with Jordan Smith of Smith House Co. to show you the best way to seal gaps in siding transitions using GE Supreme Silicone Window & Door Sealant. From exterior light fixtures to siding boards and everything in between, Smith shares tons of expert tips that will help you seal your exterior like a pro.

Here’s the Transcript:

Today we’re outside of Austin, Texas, where I’m finishing up some final details on the exterior of my house. For that, I’ll be using GE Supreme Silicone Window & Door Sealant to address the gaps in transitions on the siding.

For my first application, I’m addressing the gap between the siding boards. We intentionally leave a small gap to allow the board to expand and contract. But we need to fill that with a good sealant so that water doesn’t get back there and cause rot.

To get started, I used denatured alcohol to clean the joint, which provides a good substrate for the silicone to adhere to. I also adjust how much of the tip I cut away depending on the siding gaps I’m filling.

I really like that the GE Supreme Silicone Window & Door Sealant can expand and contract. It’s not going to crack as the weather changes, and it has strong adhesion. It’s going to stick to the wood siding tenaciously, so it’s not going to pull away as the seasons change.

Let’s Look at Lighting

The next application is for an exterior light where the electrician cut through the siding but didn’t seal around the light fixture. If left open, water could get in and cause rot. The gap on this application was a bit tighter, so I cut the tip to create a smaller hole so I could be very precise with the sealant.

I also used a caulking tool to get in around the light fixture — this let’s me fine-tune things. Another thing I really like about this product is it’s mold resistant, which means mold won’t grow on it over time. This is a highly visible area right by the door and we don’t want mold growing on it.

Quick Repair

The final application is a repair where two buildings came together. The joint was originally caulked with an inferior product, so now I’ve got to clean that product out and replace it with 100% silicone. We cut our tube with a very large opening, which allowed us to get a lot of product deep into the groove and close the gap.

When tooling the bead, it’s important not to let too much build up on the end of your finger. So I pull down a few inches at a time and then wipe my finger so I’m not touching all the sides of the buildings and making a big mess.

GE Supreme Silicone Window & Door Sealant is the perfect sealant for this application because it’s 100% weatherproof and resists UV degradation, which is perfect for this application because we get a lot of sun down here in Texas.

RELATED STORIES

  • Making Common Siding Repairs
  • Not-So-Sticky Fingers
  • Fix Air Leaks in Old Houses

Sign up for eletters today and get the latest how-to from Fine Homebuilding, plus special offers.

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
×

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

New Feature

Fine Homebuilding Forums

Ask questions, offer advice, and share your work

Log in or create an account to post a comment.

Sign up Log in

Become a member and get full access to FineHomebuilding.com

Up Next

Video Shorts

Featured Story

Fix Air Leaks in Old Houses

Simple air-sealing measures and spray-applied sealant lower energy bills and increase comfort without the need to tear the house apart.

Featured Video

Micro-Adjust Deck-Baluster Spacing for an Eye-Deceiving Layout

No math, no measuring—just a simple jig made from an elastic band is all you need to lay out a good-looking deck railing.

Related Stories

  • English Arts & Crafts Sensibility at Rumford Hall
  • Fastening an Exterior Door With Brick Mold
  • Hazard-Free Hot Tubs
  • 10 Tips for a Long-Lasting Paint Job

Discussion Forum

Recent Posts and Replies

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

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

Video

View All Videos
  • FHB Podcast Segment: When to Use Coil Stock on Fascia and Rake Trim
  • Wrapping PVC Box Beams
  • Installing a PVC Porch Ceiling
  • Creating and Installing PVC Tapered Columns
View All

Maintenance and Repair

View All Maintenance and Repair Articles
  • Restoring Polychromed Light Fixtures
  • Rescuing Old Hardware
  • Fixing Rotted Windowsills
View All Maintenance and Repair Articles

Fine Homebuilding Magazine

  • Issue 330 - April/May
    • 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
  • Issue 326 - October 2024
    • Paint Behind Strike Plates
    • Conceal Cut Ends
    • Ladder Slip Solution

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.

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

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