Repairs that can be made from underneath the house.
Many of the most common crawlspace problems can be addressed from inside the crawlspace.
If you recall from our parts of the framing discussion, bands, girders, and joists can all be repaired from within the crawlspace. Assuming there is enough space in the crawlspace to move people, materials, tools, and temporary supports around, then work can be done from underneath. In most situations, that would be a 2-foot-tall or taller crawlspace.
The subfloor is one thing that cannot be replaced from underneath the house, nor can any of the other framing portions when there is not enough room to fit people under the house to do the repairs. It seems obvious, but it’s worth stating.
Generally, the repairs to these areas are to replace the damaged boards with new boards. This means removing the old and installing new. Joists may be the one expedition to this where often they are sistered instead of being replaced; the subfloor is the reason. The subfloor is nailed to the floor joists from above. That is the strongest connection you can make between those two items, and it cannot be replicated from below. So if the flooring is going to stay in the house, the joists need to be sistered to the flooring, which remains attached to the framing.
Sistering is when two boards are nailed together so they can act as one board, in the case of the joists, the original board does the work of attaching to the floor and the new board does the work of holding all the weight.
Areas that are lacking in support can be reframed or supported from underneath as well.
Many foundation repairs are made on the outside of the home and are done from within the yard. However, things like new piers have to be built under the house.
If you happen to have a slab home, there are, unfortunately, no repairs can be made from underneath, and almost all foundation problems have to be solved by removing the flooring and going through the slab.
