How to Fix Cracks in Plaster Walls
Several advantages make plaster a popular wall covering, including its hardness, fire resistance, and noise dampening. So why has such a strong, durable material fallen out of favour?
Until the 1950s plaster walls were common, so those with older homes are familiar with plaster’s problems: It cracks. That is when you will require plaster repair in Perth
Plaster walls can be made with a variety of ingredients, but it usually contains sand, lime, and horsehair. A contractor spreads plaster on walls or ceilings after mixing it into a paste-like consistency. You can apply it thin for a smooth finish or with decorative textures such as ribbed or swirled. Drying the mixture causes it to become rock hard and brittle, which is prone to cracking.
Cracks in plaster are generally cosmetic and will not cause problems in the future. To be on the safe side, be sure to call the expert ceiling repairs for plaster repair in Perth if you notice any unusual cracks.
How Do Plaster Cracks Form?
To understand why plaster cracks, it helps to take a peek inside the plaster wall. To build a plaster wall, wooden strips called lathes are nailed horizontally across the framing. Then plaster is applied on, oozing in between and behind the lathes.
The plaster that goes over top and behind the lath strips dries hard and forms what’s called the key. The key holds the plaster and lath strips together. Then a couple more layers of plaster are applied on top and smoothed out. All those layers are brittle and have the potential to crack as the house settles or as the wall gets bumped through everyday living.
Weak Spots in Plaster
The plaster will crack most often where the wall has natural weak spots: the studs and joists, doors, windows, and the space between floors in a stairwell.
As the earth shifts, your home shifts with it. However, hard, brittle plaster does not settle well. Rather, it cracks. Cracks can occur in weak spots like doorways or framing. Typically, they spread diagonally.
It is common for plaster walls to have a few small cracks. It is easy to crack a wall in a moment of clumsiness. Cracks may even appear and disappear seasonally as materials expand and contract with temperature.
Nearly all the doors and windows in the house have cracks on their corners. These cracks are caused by settling stresses being absorbed by openings.
A pro nails lathes to solid wood in the space between floors, so wet plaster can’t ooze into the space and create an anchor. Eventually, cracks appear.
Plaster’s other weak spots are actually the house’s strongest parts. Everything settles around the chimney and fireplace, which are solid rock. This is why cracks often appear around the fireplace and chimney.
A New Crack May Indicate a Foundation Problem
The majority of settling occurs during the first decade of a house’s life. In an older home, new cracks in the plaster may indicate a foundation problem rather than a cosmetic one. Search the basement or crawlspace below for cracks. Then you might have a foundation problem that needs to be addressed.
The Best Way to Fix a Crack in a Ceiling or Wall
The easiest way to fill a plaster crack that blends in seamlessly with the wall is to caulk it before painting over it. For plaster wall repairs in Perth after you’ve cut into plaster to modernise your home, you might want to hire a plaster repair company like Perth Ceiling Repairs. Give us a call for a free inspection and quote on plaster repair in all suburbs of Perth today.