What is the difference between paver sand and polymeric sand?

Paver sand is plain sand. Coarse concrete sand is used as the 1 in bedding layer, and finer sand can be swept into joints. Polymeric sand is fine sand mixed with a binder that hardens when wetted, and it is used only in the joints.

Is polymeric sand better than regular sand for paver joints?

It holds up better against weeds, ants and washout because it sets firm. Plain joint sand is cheaper, easy to top up and easy to remove for repairs, but it needs topping up and weeding over time.

Can you put polymeric sand over regular sand?

Only if the old sand is removed to near the full depth of the paver. A thin skin of polymeric sand over loose sand cracks and lifts. Clean the joints out first.

Can I use polymeric sand as the base under pavers?

No. Use coarse concrete sand for the 1 in bedding layer. Polymeric sand would set hard in an uneven layer and stop water draining.

Paver Sand vs Polymeric Sand: Which Joint Sand to Use

Plain paver sand and polymeric sand both go between pavers, but only one of them goes under them. Here is what each is for, how they compare in the joints, and how to work out how much of each to buy.

Two jobs, two kinds of sand

A paver patio uses sand in two places, and mixing them up is one of the most common mistakes:

Where	What it does	What to use	How much
Under the pavers (bedding)	A thin, even bed the pavers are pressed into	Coarse washed concrete sand	1 in deep over the whole area
Between the pavers (joints)	Locks pavers together and spreads loads	Polymeric sand, or fine dry joint sand	Only the joint volume, a few percent of the area

The bedding layer is many times more sand than the joints. A 12 × 16 ft patio needs about 0.65 cubic yards of bedding sand (well over a ton of bags) but only about 170 lb of joint sand with 4 × 8 in pavers. The paver sand calculator handles the bedding, and the polymeric sand calculator handles the joints.

Joint sand compared

	Plain joint sand	Polymeric sand
What it is	Dry fine sand (often mason sand or bagged joint sand)	Graded sand with a binder that sets when wetted
Weeds and ants	Seeds and ants move in over time	Resists them while the joints stay intact
Washout from rain and hoses	Washes out of joints and needs topping up	Holds in place once cured
Installation	Forgiving: sweep in, compact, top up any time	Pavers must be dry, surface blown clean, watered as directed
Haze on pavers	No	Possible if sand is left on the surface when wetted
Repairs	Lift pavers and reuse the sand	Hardened sand must be broken out and replaced
Joint width	Narrow joints	Narrow joints; wide-joint versions for stone
Cost	Lower per bag	Higher per bag

When plain joint sand makes sense

Permeable or open-joint designs that are meant to let water through. Those use small chip stone, not sand; follow the paver maker’s spec.
Areas you expect to lift again soon, such as over a utility line.
Very shaded spots that rarely dry out, where polymeric sand may struggle to cure.
Tight budgets on large areas, accepting that you’ll top up the joints over time.

When polymeric sand makes sense

Patios and walkways where weeds and ants in the joints are a nuisance.
Pool decks and areas that get hosed down often.
Slopes and downspout areas where plain sand washes out.
Wider joints on tumbled pavers or stone (use a wide-joint product).

Paver joint sand: getting it in

Whichever you choose, the joints need to be full. Paver interlock comes from sand packed tight in the joints, and a joint that is half empty lets pavers rock and shift.

Sweep the sand in from several directions.
Run a plate compactor with a pad over the pavers. The vibration settles the sand down into the joint.
Sweep in more sand and compact again until the joints stay full.

With polymeric sand, stop about ⅛ in below the top of the paver, blow the surface clean, and water as the bag directs. With plain sand, fill to the top and expect to top up after the first few rains as the sand settles.

Switching from regular sand to polymeric

Polymeric sand needs depth to hold. On an existing patio, clean the old sand out to at least 1 in deep, and ideally most of the paver depth, with a pressure washer or joint-cleaning tool. Let everything dry completely, sometimes several days, before sweeping in the new sand. A shallow layer over old sand will crack and break up.

How much of each to buy

Bedding sand: area × 1 in ÷ 12 + 10%, in cubic yards or 0.5 cu ft bags. About 6 sq ft per bag.
Joint sand: depends on joint width and paver size. For 4 × 8 in pavers with tight joints, roughly 1.75 to 2.5 bags of 50 lb per 100 sq ft; for 12 × 12 in pavers, roughly 0.8 to 1.1 bags per 100 sq ft.

The paver calculator works out both, along with the pavers and base, in one go.

Questions people ask

What is the difference between paver sand and polymeric sand?: Paver sand is plain sand. Coarse concrete sand is used as the 1 in bedding layer, and finer sand can be swept into joints. Polymeric sand is fine sand mixed with a binder that hardens when wetted, and it is used only in the joints.
Is polymeric sand better than regular sand for paver joints?: It holds up better against weeds, ants and washout because it sets firm. Plain joint sand is cheaper, easy to top up and easy to remove for repairs, but it needs topping up and weeding over time.
Can you put polymeric sand over regular sand?: Only if the old sand is removed to near the full depth of the paver. A thin skin of polymeric sand over loose sand cracks and lifts. Clean the joints out first.
Can I use polymeric sand as the base under pavers?: No. Use coarse concrete sand for the 1 in bedding layer. Polymeric sand would set hard in an uneven layer and stop water draining.

Paver sand vs polymeric sand