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

Excavating an existing basement.

jcinosky | Posted in Construction Techniques on March 24, 2002 02:30am

Excavating an existing basement.

My Wife and I recently purchased a small craftsman, colonial, fixer upper built about 1935. We would like to excavate the basement to allow more usable living space in the house. The foundation is concrete block with a cement slab. The slab looks as though it was poured and patched a number of times. It is flaking in spots and obviously much thicker in others. The ceiling height, at the highest point due to the piece meal floor, is only 6’ 5″ slab to bottom of the floor joists. Then there are steam pipes, which have been added below. Ideally we would like to go down 2’ and add a bathroom and recreation area. I think my questions are these.
1. How do you sufficiently brace the foundation to allow for the extra depth?
2. Who would I hire to do such a thing?

Thanks for any help you can give.

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

Replies

  1. User avater
    DaveMason2 | Mar 24, 2002 03:22am | #1

    Condo , This is strictly something that should be left up to the pro's.

    What they are gonna do is put two steel I beams thru the foundation under the house and lift it up from the outside.Once they get it up to a heigth that they can work under they will dig out your basement , pour the slab and build the new foundation. Then they will set the house back down , pullout the beams and fill the holes.

    Usually an Excavation contractor does this kind of work.

    Good luck, Dave

    1. BungalowJeff | Mar 24, 2002 04:28am | #2

      Actually, depending on the condition of the foundation and type of soil it would be much cheaper to underpin the foundation and dig down. But, either way this is not a DIY project so an engineer is your best bet....that's not a mistake, it's rustic

    2. JohnSprung | Mar 26, 2002 01:01am | #7

      If the existing foundation is sound, how about lifting the house up the two feet, and re-building the cripple walls to keep it at that height?  It could be a cost effective solution if the climb isn't too much and your building officials will permit it.

      See FHB April 1993 for "Digging a Basement the Hard Way" -- using a bobcat under a house.

      -- J.S.

      1. JLazaro317 | Mar 26, 2002 05:35am | #8

        I think he's asking about lowering the floor (ie. busting up the concrete, digging deeper, and shoring the footings). It's do able but it's gonna be alot of work if it's a big basement.

        Good luck!

        John

        1. georgeolivergo | Mar 26, 2002 09:45am | #10

          definitely a lot of work. 2' down digs a lot of dirt.

          I kind of like Sprung's idea. what would you have to do for that, let's see:

          remove siding/sheathing, ck. utilities, etc.

          jack the house, brace first floor

          build cripple wall

          resheath/side

          remove braces

          frame, rough-in utilities, remove steam pipes, whatever

          if you excavated instead:

          brace first-floor to remove posts if necessary, etc.

          remove slab

          dig

          dig

          dig

          dig

          dig

          dig

          find somewhere to put the dirt

          pour new footings/foundation; maybe in stages

          pour new slab

          frame, rough-in utilities, remove steam pipes, whatever

          the only other thing I want to say is...if you think you're deep enough, you probably ain't!

          GO

  2. Schelling | Mar 24, 2002 05:50am | #3

    1. There are a number of ways to "brace the foundation" and you should use the way suggested by...

    2. A general contractor with experience in this type of work. This is not for everybody. A general contractor who does a lot of masonry and/or concrete work will be a likely cantidate. He will know if you need an engineer. 

  3. luvmuskoka | Mar 24, 2002 05:06pm | #4

    I've heard of a way that excavation companies can deepen a basement or crawl space using mining type equipment and a conveyor belt. They gain access thru the bilco or basement door. I saw this on a t.v. show about 10 years ago.....'this old house'?...can't remember. I think they cut dirt out a couple feet inside the original foundation and repoured a new one. Does anyone else remember seeing this?...or familiar with this technique?

    1. ahneedhelp | Mar 24, 2002 05:31pm | #5

      FH ran an article showing a wine cellar being added to house by digging under the front door with a Bobcat.

      It sure looked like a mining operation.

      Not quite the same situation but thought I would mention it.

    2. Saw | Mar 24, 2002 07:08pm | #6

      I recall that show, I believe that it was in Chicago. A row house if memory serves me right.

  4. nigelpratt | Mar 26, 2002 09:33am | #9

    call in the house removers, Move the house back/forward/to one side, do your basement work, move the house back on top of new basement.

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

Custom Built-ins With Job-Site Tools

From building boxes and fitting face frames to installing doors and drawers, these techniques could be used for lots of cabinet projects.

Featured Video

A Modern California Home Wrapped in Rockwool Insulation for Energy Efficiency and Fire Resistance

The designer and builder of the 2018 Fine Homebuilding House detail why they chose mineral-wool batts and high-density boards for all of their insulation needs.

Related Stories

  • Guest Suite With a Garden House
  • Podcast Episode 688: Obstructed Ridge Vent, Buying Fixer-Uppers, and Flashing Ledgers
  • FHB Podcast Segment: Finding the Right Fixer-Upper
  • Keeping It Cottage-Sized

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