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

$6000 House: Subfloor Repair

renosteinke | Posted in Construction Techniques on December 18, 2012 12:31pm

My much-delayed project to remodel a house I bought last year is s l o w l y getting going. I know what I want to do, and have been replacing the utilities and doing the demolition in little steps.

Last weekend, I finally gutted the kitchen, right down to the studs. The old cabinets were a hazardous waste site in their own right, and (as expected) there were signs of considerable water damage over the years.

Indeed, under the cabinets the subfloor was destroyed. Between water, mold, and simple rot, there are major holes. Now, let’s step back a moment …

The counters were along the same wall that has the bathroom on the other side. The bathroom floor, in a similar manner, has severe water damage, and a replacement patch fit in around the toilet. So, we’re talking about a significant bit of floor that needs complete replacement – perhaps a section 9-ft x 12-ft.

The original subfloor was made using 7/8″ T&G planks, laid on a bias to the floor joists.

Here’s my question: Would you repair by notching replacement planks, offsetting the joints – or would you make a square cut over the joists and just lay down some sheet goods?

Also: With the patch taking up half the kitchen floor space and 2/3 of the bath floor space …. would you just remove all of the flooring and do the complete rooms new?

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

Replies

  1. calvin | Dec 18, 2012 02:02pm | #1

    a simple question b/4 you get started

    What's the finished floors going to be?

    and what is the current joist spacing?

    Another might be, any joist damage (water or plumber related)?

    And of course, platform or balloon framed? as well as the partition wall between kitchen/ bath.

    Crawl or basement and what plumbing / electrical / heating is going to be done?

  2. renosteinke | Dec 19, 2012 03:13pm | #2

    I don't understand some of your questions, but I will try to answer what I can.

    House is 1957 typical ranch, balloon frame, over a crawl space. Floor joists are lumber, 2x8's, with a span of just over 8-ft. There's about 17" between the joists and the dirt, and joists are on 16" centers.

    I have not probed the joists, or done any other testing. Other than water stains and perhaps surface mold, I'd be surprised if there is any damage. Nor are there any notches or holes in the joists. Floor is without noticeable 'bounce.' It appears that once the water got through the floor it was able to drain freely.

    I can say this: with the removal of the old cabinets, damaged drywall, and fuzzy insulation, the kitchen no longer smells.

    Existing wall between the bath and the kitchen will be removed. A new wall will be built about  30" away from the original location.

    The wall on the opposite side of the bathroom will also be removed, and the bathroom expanded about 30" in that direction. Bathroom will 'grow,' while the kitchen and the other room will lose space.

    Plumbing will be completely different from what now is in place. The sewer line might be the only thing that stays in place. The main might be replaced with a 1" main, water heater will be moved to inside the house (it was in the carport storage shed), and every plumbing fixture will be relocated, usually by about 2-ft. Additional fixtures will be installed, including a 'walk-in' soaking tub. Copper "tree" layout will be replaced by a PEX 'manifold" arrangement. New toilet will be wall mounted. I have two vent stacks to move.

    New floors? Probably cork or rubber tiles in the kitchen and end room, while the bath will be a tile or terazzo method. Bath will likely have a heated floor as well, and the entire bath floor will be a 'shower pan.' (Hence the wall-mount toilet - one less place to leak).

    I know not what is 'platform' framing. Floor is supported on piers over a crawl space. No termite issues.

    A complete electrical re-wire is in the works; wires will be run in the walls.

    Heating is central, with a registerin the ceiling. Air Conditioning is currently a window unit, but this will be changed. I'll either add central air to the heating system, or have a mini-split with the fan heads mounted outside the kitchen.

    While the kitchen hood will exhaust out through the roof, I will probably bring in make-up air from below.

    1. calvin | Dec 19, 2012 03:58pm | #3

      reno

      The reason for the questions, if you need to get into the crawl (and it's not spacious), then getting the subfloor out will perhaps benefit you down the road.

      Platform framed-foundation, box and joists sit on that-floor is sheeted one end to the other.  Then 1st floor walls are framed on top of that sub floor. 

      See what I'm getting at-gutted in balloon frame-no problem getting the sub floor out from "under" walls. 

      Plan the job complete and see if you make it easier on yourself not having a subfloor in the way.

      On ceramic and I would guess terrazo-the diag. subfloor is not as rigid as what plywood oriented properly would be.  With natural stone and perhaps terrazo, you'll need to keep deflection down to a minimum and if the joists are sound enough, it'd be a bitch if cracks appeared because of the overspanned diagonal sheathing.

  3. renosteinke | Dec 20, 2012 09:22am | #4

    Complete Floor Replacemnt?

    So ... you're advising not to 'patch' the damaged areas by any method, but to replace the entire subfloor, wall-to-wall, in the work area?

    That can be done. Supports can be added where the edges would be unsupported. Where the saw won't reach the Multi-master will.

    A complete new floor will give me a 'plane' that moves as one piece; less chance of the finished floor cracking where the seams are.

    1. calvin | Dec 20, 2012 04:11pm | #5

      Here's what I'm suggesting.

      Figure your finish now.

      Come up with what it'll take to get there with the same quality needed, but with the least amount of total real work.

      Plan accordingly and proceed as you can.

      You know, it's how us reno guys work.  End goal in mind, most reasonable way to get there w/o losing sight of a long lasting project.

      I'm not there so am a little limited in what the exact plan should be.

  4. renosteinke | Dec 21, 2012 11:46am | #6

    Guess What I'm Doing Christmas?

    I have ordered the subfloor material; I asked for delivery next Friday. Six sheets of 1-1/8 plywood T&G subfloor grade material.

    (This town lacks a lumberyard. The guy at the Box shook his head and mutterd about never having hear of such a thing in all his 15 years in the business - only to nearly drop the phone in surprise when his supplier knew exactly what I was asking for. OK, I got charged a premium, but doo doo happens).

    This means I have until then to complete the demolition work in my house. Oh Joy. Mainly, this will mean taking out two walls (non bearing), and stripping te remaining walls to the studs. It means more temporary fiberglass insulation and temporary cardboard wall coverings.

    Temps will be mild for December, reaching the 50's during the day. Still, I'll be giving the furnace a workout while the floor is open. For that reason, I'll probably do the floor in sections, one sheet at a time. I expect I will really like my Multi-master by the time I'm done; with the change in floor thicknesses, I will have to make my seams right at the wall line.

    I've cut through the floor before, when I installed an access hatch for the crawl space. The task - subfloor covered by 1" oak flooring - really made me appreciate the added power and stability of my Makita "hypoid" saw.

    1. calvin | Dec 22, 2012 07:09am | #7

      Eat your heart out..........

      We'll be off to Nashville for a family visit-

      ha ha ha.

      With all the presents we'll be hauling, no room for tools.

      I won't be doing a damn thing but playing with the grandkids.

      Best of luck and Merry Christmas!

      By the way, I have had a MM for years and rely on it often.  You've heard me rave on it's uses.

      But,

      I think I'd rely on my sawzall (with maybe fine tuning by the MM) on most of the hard to get to or close work demo.

  5. renosteinke | Dec 26, 2012 12:23pm | #8

    Platform? Balloon? Well...

    Platform? Balloon? Well - my lack of vocabulary aside ... does it matter?

    The original question assumed I'd match the original thickness, and I asked: piece in new boards on a bias, or just cur a square for a bit of sheet goods? A question artfully dodged, and rendered irrellevant as the plan was refined.

    I'm simply not worried, in the least, about the specific floor finish to be used. I figure a good, solid subfloor can have any top layer you might want. With this remodel, the finish flooring won't be done for a year or two; I might lay a sheet of vinyl as a temporary measure. Most of the house has the floors covered by sheets of cardboard right now.

    Sawzall my patootie. I expect my primary tool for cutting the old floor out will be a Makita hypoid saw. The depth control for that saw is awesome. Multi-master will be reserved for those few areas where I'll really need to cut flush to the existing framing.

    My whole plan / rythm took a hit at the very start, in the wee hours this morning. A rather modest winter storm killed my power for eight hours - hard to do much without lights, power, or heat. When inside temps dropped to 48 I bit the bullet and visited the all-night Wall-mart for a kerosene space heater and some candles. The space heater got one room up to 60. (Outside temps were near 30).

    One thing nice about leaky old construction: you can use a space heater. That can quickly become a problem in 'airtight' construction. In Nevada a few years back, a construction worker died from carbon monoxide poisoning as he used a gas-powered saw in a properly 'tented' area. The same plastic that kept the dust 'in' also kept the fresh air 'out.'

    FWIW, the power was restored in fits and starts, with low voltages and an intermittent leg. This was followed by two more hours of no power. Moral of the story? Well, it really stresses the need for a quality transfer switch if you have a generator, a switch that won't switch back to 'grid' power until the grid has full voltage.

    Ion-type smoke detectors, btw, are extremely good at telling you when you have lit a candle.

    Anyway, the plan is Demo walls - demo floor - new subfloor - make my final layout - frame new walls - get the plumber in. Might even have a water heater by summer

    I suspect the same storm that cut my power will push the materiel delivery to next Monday, even Wednesday. We'll see.

    Last Sunday I finally dropped the roof of the old laundry addition. Paul Bunyan could not have dropped that roof more precisely; I got lucky.  With the final cut, it swung away from the house, flipped, and laid itself flat on the lawn.  It remains for me to demolish the "foundation" of this addition. This will clear that area for placing a slab for the air conditioning equipment.

    1. calvin | Dec 26, 2012 01:47pm | #9

      Hey Reno

      If you don't want answers, don't ask.

      Subfloor/joists?   any subfloor can support a finished floor?   Say you use large profile stone?

      I know, it's a shack-you ain't putting stone in.

      Then fine.

      Scab in whatever  you feel like. 

      Balloon/Platform?

      Maybe now you know the difference?   or who cares?  Either way, it could have made a difference on the advice you would be given regarding the demo of all/part/none..........of the subfloor.

      And I'll defer on your tool choice, you're there-we aren't.  But how dumb do you take us for?  of course you'd use a circular saw for all but the inaccessible cuts.  Who wouldn't?

      Nice listening to you.

      Best of luck on the project.

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

Drafting the 2027 IRC

Key proposals for the next edition of the International Residential Code tackle room sizes, stair specs, emergency egress, and deck guards, among other requirements.

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

  • Midcentury Home for a Modern Family
  • The New Old Colonial
  • Modern and Minimal in the Woods
  • Bryce Hollingsworth, Dry-Stone Waller

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 333 - August/September 2025
    • A Practical Perfect Wall
    • Landscape Lighting Essentials
    • Repairing a Modern Window Sash
  • 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

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