A plywood subfloor will bridge any minor waves in the existing floor and leveling compound would help too.
Sagging second story floor joist.
Upon removing the old plaster and latte boards i confirmed what i.
A dip or slope in the floor could indicate one or more saggy joists beneath the subfloor.
Jacking them up too fast may cause cracks in the walls and floors overhead.
Sagging can be the result of undersized joists an undersized support beam or support posts that have rotted at the bottom or settled into the ground.
Set a hydraulic jack and post under the beam and jack up the joists about 1 8 in.
Still if asked to span too great a distance i joists will bounce.
But when tom sisters or stiffens the underside of i joists he uses plywood.
Second floor joists are nailed to the bearing walls and supported by a piece of stock called a ribbon board in this case 1 6 stock let into the studs see drawing right.
The method used to fix the problem depends on the reason the joist is sagging and the number of joists.
Sagging floors are often the symptoms of structural damage to the floor joists below the surface.
Bounciness is usually caused by undersized floor joists.
Common reasons for sloping or sagging second story floors.
On the top side of the floor another fix it idea to lay down new hardwood over the existing floor.
For sistering cut inch plywood into long strips the same width as the joist s web.
Tack a beam under the sagging joists.
Depending upon the conditions it is possible to strengthen or repair existing framing members such as floor joists or roof rafters by adding reinforcing material sandwiching the member on either side with plywood is sometimes worthwhile but the plywood must be installed correctly for greatest strength.
We have a large bedroom on the second story above a large bedroom on the first floor each about 12 x 18 ft the downstairs bedroom.
Termites can rot or damage the joists typically made of wood rendering the pieces unable to hold up the floor.
Thre ways to fix a sagging or sloping floor.
Load bearing wall removed or altered on first floor.
I am in the process of remodeling and am currently redoing the ceilings in the dinning room and living room.
If a load bearing wall is removed on the first floor then the second story floor joist or trusses may drop down in the area where the load bearing wall was removed.
You will have to make sure your joists can handle the addition of considerably more weight from the plywood subfloor and any floor coverings.
To prevent the collapse of your second story or injury from falling through a rotten floor you must repair the joists as soon as possible.
Nailing two 2x4s together will work to span about three joists unless the sag is under a weight bearing wall.
Sagging second story floor joist.
As a rule the same kinds of methods that take the bounce out of solid lumber floors work for i joists.
A day until they re level.
