Restoration Guide: Walls, Floor and Ceiling Structures

Editor's Note: This is article 2 of 6 in Chapter 5: The Partitions, Ceilings, Walls, Stairs Guide of Old House Web Restoration Guide. This guide was developed and edited for old homes from original materials in the U.S. Housing and Urban Development Rehab Guide.

2. FLOOR AND CEILING STRUCTURAL ASSEMBLIES

Section 1--Overview

Many old houses have had the good fortune of regular maintenance, while others have obviously suffered years of neglect. This section helps you with assessing and repairing the structure of floors and ceilings in an old house, including the most common problems, such as sagging floors, weakened joists, and sound issues.

Section 2--Common Problems for Floors and Ceilings

Some of the most common problems you will face when dealing with old house preservation include beam strength that has been compromised by extensive notching for framing; joists that have been excessively cut; splitting joists; incorrect spacing of support beams; and deterioration of supporting posts. This guide offers ideas on how to correct these common issues:

1. Add Support to Existing Main Beams. Main beams can be reinforced with steel columns, wood columns, and even masonry piers. These methods will reduce the span of the beam, thus making the floor above it more stable. Jacking up a sagging beam is also a possibility, though keep in mind that long-term settling can be impossible to eliminate.
2. Support Beams and Joists. Sistering, or adding support with steel or wood reinforcements, might boost the performance of beams and joists. Adding steel plates or wood pieces and securing them with a heavy bolt and lock washer is a common method.
3. Transfer the Load. If a joist has been excessively cut or notched, it might be possible to transfer the load with a header joist, which is end-nailed across the cut end of the interrupted joist.

Section 3--Floor Framing: Alternatives to Solid Lumber

Reinforcing the framing of an old house can be done in a multitude of ways. Steel flitch plates, structural composite lumber, and engineered wood I-joists are just a few of the ways in which traditional products can be repaired and restored.

1. Repairing a Truss Plate. The most important part of floor trusses are the metal connector plates. If the plates have shifted, disengaged, or have suffered serious moisture or salt damage, solutions might include wood gusset plates or additional hand-driven plate connectors.
2. Metal Plates to Connect Trusses. Lumber held together by a punched connector plate offers more stability and makes it easy to run plumbing, wiring, and ductwork, but has to be handled more carefully than traditional components.
3. Glulams. Glued laminated timbers are wood laminates bonded together to form beams of varying sizes. They are great for large spans and heavy loads, and work well in replacing rotting beams and other damaged elements in the structure.
4. Wood I-Joists. Often used in light frame construction, I-joists have a shape that simulates that of a steel I-beam. They are very lightweight, easy to install, and use less wood, making them an environmentally-friendly option.
5. Laminated Veneer Lumber. Consisting of layers of kiln-dried wood pressed together, this combines the best qualities of natural wood and engineered wood.
6. Parallel Strand Lumber. The sections of wood that are not suitable for LVL are combined with structural adhesives and then formed with heat and pressure. The stiffest and strongest of composite lumber products, it is used where both strength and appearance matter.
7. Laminated Strand Lumber. Often longer than the PSL counterparts, this composite lumber is used for beams and headers, though some builders are also using it for studs.

Section 4--Home Restoration After Moisture Deterioration

Water is one of the most damaging elements your old house structure has faced over the years. Moisture absorbed by wood framing can lead to issues with warping, weakness, decay, insect infestation, and more. Lumber that has decayed can be reinforced in the hopes of preservation, rather than total replacement.

1. Epoxy Repairs. If you have a need to preserve a certain area for historical purposes, epoxy might be your best bet, though it is not recommended for widespread rot damage.
2. Supporting the Joists. Vertical support beams and reinforcements alongside the joists and at the ends are all good techniques to reinforce areas that have rotted or decayed.

Section 5--Floor Framing with Fire Damage

The extent of fire damage on a structure can vary wildly, from mild smoke and water damage to wide-spread disaster that makes home restoration impossible. Careful assessment by a home restoration contractor will probably be necessary in deciding whether a fire-damaged structure can be repaired.

1. Restoring Structural Members. Much heavy timber construction can remain in place as long as charred areas are removed and the structural integrity remains intact. Sheathing will have to be replaced, and smoke damaged areas should be deodorized and cleaned thoroughly.
2. Salvaging Glulams. Often fire-damaged glulams can be salvaged and reused, and can retain their structural integrity; however, they may also retain the odor of smoke.

Section 6--Soundproofing

Sound usually travels as vibration, and can be caused by everything from a washing machine to a heavy foot on a wooden floor. Assessing and repairing the structure of floors and ceilings includes determining the source of sound issues in order to reduce or eliminate them.

Adding cushioning material to floors, such as carpets and underlayments, can help reduce the impact of footsteps and other movements. Floors that are not conducive to cushioning, such as kitchen or bathroom floors, can benefit from the use of cork, sound-deadening boards, matting, and the like. Other options include specialized insulation, sound mats under the finished floor, and the addition of mass.