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

Subfloor Question

| Posted in Construction Techniques on March 29, 2002 02:23am

Hey Fellas,

I just got finished ripping up my floor in the bathroom. It was rotted so I took it down to the floor joists. I saw-zalled it around the perimeter and once I got it all up I realized I have to support the perimeter somehow and also have a nailer for the deck and subfloor. I have some wide gaps in some spots maybe 6-8″ to the stud, but in others only a few inches. Any ideas how I can get a nailer around the perimeter and also provide the necessary support. I need to make up 2′ to come level to the toilet flange, so I plan on putting down 3/4″ply and then 1/2″ over that and then 1/2″ Hardibacker and finish it with 3/8″ x 16″ tile. Suggestions would be well appreciated.

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

Replies

  1. JohnSprung | Mar 29, 2002 03:28am | #1

    I don't understand what you mean by gaps of 6-8" to the studs.  Is there that much of the old subfloor left alongside a wall?  Do the joists run parallel to a balloon framed wall?

    In any case, you might consider lowering the toilet flange, and dropping the subfloor down between the joists, supported by 1x2 ledgers nailed to the sides of the joists.  That way you can get the finished tile floor in the bath much closer to the level of the floor outside.

    -- J.S.

    1. Rickyman2 | Mar 29, 2002 02:37pm | #2

      John, What I meant by "gaps" is that there is that amount of space between the bottom plate and the closet stud. As I said in my post I took a sawzall to the whole perimeter. There is no piece of floor left at all. The floor joists run two different  directions, so at some point, yes, the do run parallell and others, no. I don't want to lower the flange etc.. because the height of the old flange and "outside" floor matched up fine before I ripped the floor out so I'm not going to change that. That's why I'm making up the 2" with 3/4", 1/2" and 1/2" Hardibacker with 3/8" tile. I just need to figure out how to support the perimeter. I'm stumped.

      1. JohnSprung | Mar 29, 2002 09:16pm | #3

        I'm still not seeing the picture here.  It sounds complicated with joists running in two directions.  Under those circumstances about all I can say is that there might be things you can do with joist hangers and the same size lumber as the joists to get good solid support where you need it.  If possible, post some pictures.

        -- J.S.

        1. Rickyman2 | Mar 30, 2002 05:10am | #4

          John,

          The bathroom is upstairs that I'm working on. If you walk in the door,your looking at the far wall (outside of house). From the mid-point of the room to the outside walls the floor joists run vertical, I believe they support the cantelever on the front of the house. Now from the mid-point toward the door entrance the floor joists run parallel to the exterior wall. That's the joists running two different directions as I mentioned. Now, I'll see if I can try to make this clearer for you about what I'm trying to do. When the bathroom walls were erected in this house the floor plates were laid on the decking but not precisely over floor joists, so when I cut out the decking around the perimeter I was left with floor plates that are running down the middle of floor joists, with nothing underneath them. Picture laying two floor joists on the ground 16" apart, put a piece of plywood on top of these joists and place a 2x4 on top of this piece of plywood, let's say in the center of the plywood( which would mean there is no joist under the 2x4, okay? Now, cut out and remove a piece of the plywood from one side of the 2x4 and you'll be left with two joists with a piece of plywood nailed on one side with a 2x4 suspended on the plywood at the midpoint of the two floor joists. Picture this 2x4 as the floor plate of the bathroom and that's where I'm at. Are you picturing this a little better? I had no choice but to cut out the whole floor because of the condition of the floor, but I never even thought about the floor plates running parallell and in between the floor joists. So now I have to get some support and nailers or "something" in there.                                  Rick

          1. richdes | Mar 30, 2002 06:47am | #5

            Sounds like you got some ceiling patches ahead of you. The only thing i can think of is to get at it from below and put in some blocking in between the floor joists, if you just open up the one bay you can toenail them in. If the wall above is a bearing wall then you might want to consider joist hangers but i think it may be overkill so long as you can nail them well with #12 nails. 

          2. User avater
            Mongo | Mar 30, 2002 07:25am | #7

            Ricky,

            What a pain.

            You need blocking of some sort to suport that wall. It's gonna be tough with limited access.

            I'll assume (yea, yeah) that your current joists are 2x10s. Is there any chance that you could glue and screw a 2x4 ledger to the inside face of the two joists that make up that joist bay, set so the top of the ledger is 5 1/2" below the top of the joists? Figure 9.5" deep joists. 3.5" deep ledger. 2x6 blocking, which is 5.5" deep. That leaves a half-inch gap (9.5"-5.5"-3.5"=0.5")

            Here's an idea:

            Get a couple of small half-inch pieces of wood to be used as spacers/shims. Place them in each bay, in the bottom corners where the drywall from the celing below meets the bottom of the joist.

            On top of those half-inch spacers, place your 2x4 ledger. Before placing, predrill holes for structural (not drywall) screws, start the screws, and lay a few beads of construction adhesive on the back side of the 2x4 to adhere the 2x4 ledger to the joist. Screw the ledger to the joist. The spacers, plus the thickness of the ledger, should place the top of the ledger about 5.5" below the tops of the joists.

            Repeat, screwing a ledger to the inside of the other joist.

            Cut 2x6 blocking to fit the width of the bay. Predrill screw holes in the ends to "toe-nail" (toe-screw) the blocking to the joists. These will be tough to install with limited room, etc...but realize that the ledger will take the brundt of the load, the "toe-screws", while also distributing load, are primarily to hold the blocking vertically. If you can toe-screw from both sides of the block, great. If only from one side, that's just as good. If you want, you can double up the blocking (two 2x6 blocks glued and screwed together to make a true 3.5x5.5), but don't double it up before you install it or you may not be able to wedge the thicker block in place. Install one, then install the second, sistering it to the first.

            This blocking should be sufficient to support the non-bearing partition wall. One last item:

            Though your subfloor/underlay/cement board sandwich will be plenty strong, you may still want to install additional support...say a 2x4 on edge...between the blocks, and running next to and parallel to the sole plate on your now-floating partition wall. This will give just a little bit more support to the subfloor where it meets the sole plate.

            I hope all that makes sense...don't forget to measure what lumber you have and adjust the layout accordingly. Good luck with whatever you do.

          3. richdes | Mar 30, 2002 02:58pm | #8

            great solution Mongo i hope ricky can get in there to do it. he can just through nail or screw from the open joist in the bathroom no need to toe screw/nail.

          4. Rickyman2 | Mar 31, 2002 03:17am | #9

            A pain indeed Mongo, Thanks you guys for the suggestions, I'll let you know how I made out when I'm done (and after the Tequila hangover wears off!)

          5. andybuildz | Apr 01, 2002 02:17am | #12

            Mongo.....you rock dude.you definatlly da man...if your ever in NY I could use a good man like you...be well...AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM

  2. Geoffrey | Mar 30, 2002 07:02am | #6

    Rick, where the walls run parallel to the joist put a block(headout) on each end as close to the perpendicular walls as possible then put a joist under the old flooring so it's half on and half off , then install your subfloor, you could even double the joist if you want a wider "ledge" for nailing. hope you get what I'm saying! I think you do

                                                                             Geoff

    1. Rickyman2 | Mar 31, 2002 03:32am | #10

      Hey Geoff, Can you explain the block/headout to me so I'm sure I'm thinking what your thinking? Mongo had a good idea also.

      Thanks Rick

      1. Geoffrey | Mar 31, 2002 09:38pm | #11

         Hey Rick,     yea, think of a head- out for a toilet or similiar plumbing, you're just adding a joist in the middle of the existing bay which has the non-bearing wall running down the middle of it. You block or "head-out" the added joist at some point where you can still reach to install a block at either end of the new joist. You'll probably have to toenail the blocks, but you might be able to get a joist hanger in there as well , maybe not , you're call. Either way you can install a hanger on the head- outs to accept the new joist.

              Hope I didn't make it any more confusing,

                                       Geoff

    2. JohnSprung | Apr 01, 2002 08:22pm | #13

      Geoff's solution is the kind of thing I was thinking of.  If you have compressed air available, this sort of thing is a natural for palm nailers.  I'd do it with joist hangers.  First, for either a headout or joist, cut the piece of wood and check that it fits (or pieces if you're going to sister two).  Then put the joist hangers in place, but nail only the far sides of them.  You can then bend down the near side of the hangers just enough to get the wood in.  Push the wood and the near side of the hangers firmly into their final position, and nail them home.  If you sistered two joists, nail them together.

      Hopefully you can do all this without having to mess up the ceiling downstairs.  It sure helps to keep the rest of the family less unhappy about the disruption.  If it's a lath and plaster ceiling, you may have to carefully break some of the plaster keys out to make room for the bottom edge of the lumber.  If that makes the plaster too weak, you can also squirt some yellow woodworking glue between the lath slats and the plaster to secure it.

      -- J.S.

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

Mortar for Old Masonry

Old masonry may look tough, but the wrong mortar can destroy it—here's how to choose the right mix for lasting repairs.

Featured Video

How to Install Cable Rail Around Wood-Post Corners

Use these tips to keep cables tight and straight for a professional-looking deck-railing job.

Related Stories

  • Fire-Resistant Landscaping and Home Design Details
  • A New Approach to Foundations
  • A Closer Look at Smart Water-Leak Detection Systems
  • Guest Suite With a Garden House

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 332 - July 2025
    • Custom Built-ins With Job-Site Tools
    • Fight House Fires Through Design
    • Making the Move to Multifamily
  • 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

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