Quartz countertops have become increasingly popular in recent years due to their durability, aesthetic appeal, and low maintenance requirements. One common question that arises with quartz countertops is whether or not they are porous. The porosity of a countertop material is an important factor to consider, as it impacts maintenance, durability, and stain resistance.
What is Porosity?
Porosity refers to the tiny holes and pores that exist within a material. A porous material, like natural stone or concrete, has many small voids spread throughout its surface. These voids allow liquids and gases to seep into the material, which can lead to staining and damage over time.
A non-porous material, on the other hand, does not contain these pores and voids. The solid surface resists liquid penetration, which makes the material highly resistant to staining and easier to clean and maintain. Glass, metal, and plastic laminates are examples of non-porous materials.
Are Natural Stone Countertops Porous?
Natural stone countertops, like granite, marble, and soapstone, are highly porous. The natural stone is formed over time by high heat and pressure, which creates many microscopic holes and cracks throughout the surface. As a result, stone countertops are very prone to absorbing liquids, leading to staining, etching, and darkening of the surface over time.
Sealing natural stone can help reduce porosity and make the counters more stain-resistant. However, sealers wear off over time and need to be reapplied regularly. Even with sealing, stone countertops will still be more porous and require more maintenance than engineered quartz.
What Makes Quartz Less Porous?
Quartz countertops are engineered from ground natural quartz crystals combined with resins, polymers, and pigments. The manufacturing process makes quartz non-porous and stain-resistant:
- Quartz Density: Natural quartz is very dense and non-porous. When ground into a fine powder, it maintains its low porosity.
- Binder Resins: Added resins fill any pores or voids between the quartz particles, resulting in a solid surface.
- Vibratory Compaction: The quartz and resin mixture is compacted under vacuum and vibration, forcing out any air pockets and minimizing pores.
- Extreme Heat and Pressure: High pressure and heat fuse the mixture tightly together into slabs, further reducing porosity.
The combination of dense quartz, binder resins, and manufacturing under heat and pressure results in an engineered stone that is non-porous, stain-resistant, and easy to maintain.
Is Quartz Completely Non-Porous?
Quartz countertops are often referred to as “non-porous.” However, no material is 100% impervious to liquids. The resins used in manufacturing quartz can be mildly absorbent. Over time, some staining agents might soak into the surface. However, quartz has minimal porosity, especially compared to natural stone.
According to most sources, quartz has a porosity rating of less than 0.5% when properly sealed. This makes quartz practically non-porous. Liquids sit on the surface rather than soak into the material. Quartz is also unaffected by etching acids like vinegar, lemon, and wine.
Benefits of Quartz’s Low Porosity
The low porosity and non-absorbent nature of quartz provide important benefits:
- Stain Resistance: Resists most common kitchen stains like wine, coffee, oil, and juice that can ruin other surfaces.
- Long-Lasting Color: Does not absorb liquids that can discolor the surface over time. The vibrant color lasts for years.
- Food-Safe: Resists absorbing bacteria, mold, and microbes that cause stains and odors.
- Easy Maintenance: Does not require sealing. Simple cleaning with soap and water is all that’s needed.
- Durability: Impervious to chips, scratches, and damage from exposure to moisture. Does not harbor bacteria or mold growth.
- Heat Resistance: Very resilient against thermal shock, damage from hot pans, and high temperatures.
For most homeowners, the ultra-low porosity of quartz provides the best combination of aesthetic beauty, durability, and easy maintenance when compared to other countertop materials.
Does Quartz Need to be Sealed?
Sealing is not necessary for quartz counters. In fact, sealers can create more problems:
- Added Expense: Sealers cost money to purchase and add a recurring maintenance cost.
- Can Cause Build-Up: Sealers can congeal on the surface and cause hazy spots.
- Traps Contaminants: Anything spilled on the counters can be trapped under the sealer.
- Can Discolor Over Time: Some sealers yellow or discolor with exposure to light.
- Gives False Sense of Security: Sealers give the impression you don’t need to be careful, leading to damage.
The top quartz manufacturers agree that sealing does not improve stain resistance. In fact, it can do more harm than good. Quartz’s durability and stain resistance come from within the material, not from topical sealers.
How to Keep Quartz Countertops Looking Like New
While quartz requires minimal maintenance, following these care guidelines will keep your counters pristine:
- Clean spills promptly to prevent any possible staining, especially oil and grease.
- Use mild soap and water for regular cleaning. Occasionally disinfect the surface.
- Avoid abrasive cleaners and scrubbing pads that could dull the finish.
- Rinse off citrus juices, wine, and tomato sauce to prevent acidic etching over time.
- Don’t place hot pans directly on the surface. Use trivets and hot pads.
- Re-polish minor scuffs and scratches with a stone polishing kit.
- Deep clean the counters 1-2 times per year with a quartz-specific cleaner.
With occasional cleaning and by avoiding damage from cuts, heat, and excessive pressure, quartz countertops will stay looking like new for many years. The low porosity and stain-resistance make quartz one of the easiest to care for countertop materials.
FAQs About Porosity of Quartz Countertops
Is quartz poreless?
Quartz is not 100% poreless, but it is as close to poreless as possible. The tiny amount of porosity in quartz is negligible. Under normal conditions, liquids will not penetrate the surface. This makes quartz virtually non-porous compared to materials like granite, marble, concrete, and wood.
Can liquids soak into quartz?
In general, liquids do not soak into properly sealed quartz. Minor absorption may occur over time with certain materials, especially oils, but the amount is minimal. Quartz resists absorption and staining better than any natural stone countertop.
What about scratches and chips – are they porous?
Scratches, chips, and cracks in quartz can provide a pathway for liquids to penetrate into the surface. This is why it’s important to smooth over any damages to maintain water- and stain-resistance. Epoxy resin can be used to fill any chips and voids.
How porous is quartz compared to granite?
Granite is highly porous, with a rating between 0.4% and 1.5%. Quartz has a porosity rating of less than 0.5% when sealed, making it practically non-porous compared to granite. Unsealed granite requires regular sealing to help reduce porosity.
Can liquids get under quartz countertops?
It is possible for spills to seep into the tiny seam between the quartz and the cabinet. Use caulk or adhesive sealant when installing quartz to prevent moisture getting under the counter’s edge and causing swelling or separation.
Does thickness affect porosity?
No, thickness does not affect porosity. Porosity is determined by the material composition and manufacturing process, not the thickness. Both 2cm and 3cm quartz slabs will be non-porous. Thicker quartz is more durable and resistant to chips and cracks.
How does porcelain compare to quartz porosity?
Porcelain is highly impervious to moisture with a porosity rating near 0%. However, porcelain can crack or chip more easily. Quartz has slightly more porosity than porcelain but is more flexible and resistant to chips. Both offer stain protection.
To conclude, quartz has a porosity of less than 0.5% meaning it is non-porous compared to many other countertop materials. The densely packed quartz, binding resins, and manufacturing process results in an impervious surface that prevents liquids, molds, and bacteria from absorbing into the material. With simple care, quartz countertops will remain in great condition while retaining their non-porous qualities. The low porosity makes quartz one of the most durable, stain-resistant, and low maintenance options for kitchen countertops.