Without question, any hairline cracks in your walls should be repaired before putting your home on the market since these may decrease the value of your home in the near future. You don’t want prospective buyers coming in and thinking there’s a problem with the foundation or something that they don’t know about, which could cause a greater expense.
It may be superficial, but they don’t know that. That advice holds true regardless of the age of your home. People want to see it clean and nice, whether it’s a historical property or new construction. You never want a prospective buyer to start speaking about your property in a disparaging way.
Superficial cracks in walls happen for several reasons. According to most construction and property experts, where wood meets plaster or plasterboard, you can get cracks. Plasterboard does not move very much, but wood expands and contracts, and eventually, cracks open up. The walls around doors and windows can also be problematic. As you open and close them, there’s some minute movement.
Over time, cracks can appear there as well. Fortunately, those fissures are easily repaired. But while it’s possible to simply fill them with spackling paste or paint, that approach is not highly recommended. With the next change of seasons, it will just open up again. Instead, the best suggestion is to apply self-adhesive fiberglass mesh tape over the cracks, then covering the tape with joint compound.
When the crack reopens, it happens underneath the tape and you don’t see it on the surface. For a seamless repair, the joint compound should be feathered out over a larger area, about 10 or 12 inches in either direction to make it imperceptible. There are other kinds of cracks that frequently appear on walls. When there’s extensive cracking over a whole wall, more like crazing, that’s usually a paint-film failure.
To deal with that, the best recommendation is covering the entire wall with a new layer of thin plasterboard or with large rolls of fiberglass mesh tape and joint compound. Cracks sometimes indicate a more serious, structural issue. If your wall has large, deep canyons running through it, mesh tape and joint compound are unlikely to provide a satisfactory repair. In that case, it may be time to call a professional who can get to the root of the structural problem.