In A Hour.com
Most finished floors will develop
squeaks at sometime or another. 
A typical floor consists of joists -
which stretch from an exterior
wall; bridging between the joists
(to prevent sagging), and the
subfloor adds rigidity.

Temperature and humidity
changes cause the various floor
parts to shrink and swell at
different rates.  The result:
Squeaks develop where loose
boards rub against each other
or against loose nails.

If joists below the squeaks are
concealed, you'll have to repair
the squeaks from above.  This is
accomplished by drilling pilot holes at 45 degree angles directly into the floorboards (to keep the wood from splitting).  Then you need to drive in ring-shank or cement coated flooring nails.  Use these nails because smooth nails might work loose, causing the squeak to reoccur.  Using a nailset, countersink the nail heads about 1/8 inch below the surface of the floor.  Fill the nail holes with wood putty.  Mound the putty slightly, let dry, and sand flush.

If the joists are exposed and you have access from below, you can treat those squeaks easily.  Watch while someone walks over the noisy spot.  If the subfloor moves, use a tapered shim to tighten a loose subfloor board.  Dip the shim tip in glue and tap it between the joist and subfloor until it's snug.  To tighten a series of boards, force a 2x4 up against the subfloor using a temporary prop.  Nail the 2x4 to the joist.  Repeat on the other side of this joist.
If there is no movement when looking underneath at the subfloor, then this may mean the finish floor is loose and needs to be pulled down with screws. 

Pull loose finish boards using 1 1/4-inch roundhead screws. 

Drill pilot holes and use washers so screws won't pull through the subfloor.
Also, If the bridging isn't tight between joists, drive in new, larger nails at an angle.  If squeaks persist, add steel bridging.  Push it up against the subfloor, then nail it to the bottom of the joists.

If a floor has a major sag in it, you may have to add a supporting jack post under it.  Break out a section of the basement floor and pour a 24x24x8 inch concrete pad for the post to sit on.  Let the concrete cure for a week.  Place the jack post on the pad and a 4x4 pressure-treated beam long enough to span several joists on top of the jack.  Screw the jack up until the beam is snug against the joists, then raise one-quarter turn more.  Wait a week and make another quarter-turn, continuing this process until the sag is gone.  Don't lift faster, or you may cause structural damage.

Fixing Subfloor Problems With Access From Below

Related Articles
Installing Traditional Wood Floors
Shopping For Hardwood Flooring

Related Videos
Video: How To Repair Squeaky Floors
Flooring Videos
Advertisement
Comments?

Miscellaneous Articles

Using A Power Washer
Building Wood Steps For A Deck
Your Choices In Siding
A power washer is one of the best methods for removing dirt and peeling paint, but don't try to use it to strip all of the old paint... read more
When planning to build your deck stairs, the main thing to remember is locating them in the safest, most accessible space... read more
Whether you are doing new construction or planning a major face-lift for your existing home, you should choose siding...        read more
Videos      DIY Projects      Interior Spaces      All Spaces
Articles
How To Videos
Follow
Kitchens
Bathrooms
Heating And Cooling
Doors And Windows
Interior Spaces
Electrical
Roofing
Kitchen And Bathroom
Floors
Door And Windows

Walls And Framing
Painting

Fences And Decks
Twitter
Facebook
Outdoors
Painting
Floors
Plumbing
Walls And Framing
DIY Projects
Heating And Cooling
Plumbing
Safety
Basement
Electrical
Other Projects
DIY In A Hour.com
© DIY In A Hour.com - Sitemap - Privacy PolicyAbout Us - Terms Of Use

What Next?