Sagging in the floor can be traced to one or more of the following causes:
1. Warped or shrunken floor joists which allow the floor and subfloor boards to sag to the new level.
2. Sagging girder due to supporting posts having been pressed into the ground through failure of the footing under the posts.
3.Crumbling foundation under the outer ends of joists or girder, allowing the floor to sag at the end rather then the center.
A floor with a bounce to it (and this trouble is usually accompanied by considerable squeaking) may be caused by these same failures. However, in this case, the nail holding down either the finish floor or the subfloor may have pulled loose from the joists and the for is depressed only to the joists level when there is weight on it.
Less common is the floor that bounces owing to the fact that the joists are too small to carry the weight on the floor and a live load causes the entire floor structure to vibrate. This type is really dangerous, but rare.
Examination of first-floor timbers is relatively easy where there is a basement with the substructure exposed. Floors over crawl spaces are easily checked also, if no insulation has been applied. Have someone walk over the floor above and check carefully which part of the floor and which supporting timbers vibrate. Check the foundation at points where joists and girder rest. Brick is usually the first foundation material to show signs of crumbling, then poor quality concrete, then stone. Where the house is supported on piling and the " foundation" is actually a ring of heavy timber supported on posts or piles, this timber may be rotted or damaged by termites.
CONTINUE.....................
No comments:
Post a Comment